From d4a4d5b25b745be7f18e6916968de391e54a07a0 Mon Sep 17 00:00:00 2001
From: mutantsan We need to set the The CKAN instance will be initialized, because we will call validators and helpers in this code. Therefore, you'll need
+another environment variable to set the CKAN configuration file path: The config file must enable the If you're working on the documentation, you can run the following command to start a live-reloading server without
gathering the chart types fields data. It will speed up the process significantly, as we won't need to wait for the
CKAN initialization: This extension, ckanext-charts, provides additional functionality for working with charts in CKAN. It allows users to create, manage, and visualize charts based on data stored in CKAN datasets. The extension includes features such as chart creation, chart editing, chart embedding, and chart sharing. It also supports various chart types, including bar charts, line charts, pie charts, and more. With ckanext-charts, users can easily generate interactive and visually appealing charts to enhance data analysis and presentation in CKAN. See the documentation for more information. To install To run the tests, do: We are using We need to set the If you're working on the documentation, you can run the following command to start a live-reloading server without gathering the chart types fields data. It will speed up the process significantly, as we won't need to wait for the CKAN initialization: AGPL Configuration options There is a number of configuration options available for the extension. You can set them in the CKAN configuration file or using the admin configuration page. Cache strategy for chart data. Options: Type: Default: Time to live for the Redis cache in seconds. Set to Type: Default: Time to live for the File cache in seconds. Set to Type: Default: Enable cache for the charts. If the cache is disabled, the chart data will be fetched from the data source every time the chart is rendered. It could lead to performance issues if the data source is slow or the data is too large. Type: Default: Include HTMX assets. Could be disabled if another plugins are including it. Type: Default: Reinit CKAN JS modules after HTMX swap. Type: Default: By default, only authenticated users can build charts. If you want to allow anonymous users to build charts, set this option to Type: Default: The extension provides an admin configuration page where you can set all the listed configuration options. The admin page available only using an extension This page could be accessed by the following URL: Check if anonymous users are allowed to build charts. True if anonymous users are allowed to build charts, False otherwise. TYPE: Get the columns of the given resource. Resource ID TYPE: JSON string of columns options TYPE: Checks if the HTMX asset should be included. True if the HTMX asset should be included, False otherwise. TYPE: Checks if CKAN JS modules should be reinitialized. True if CKAN JS modules should be reinitialized, False otherwise. TYPE: Check if the user is authenticated. True if the user is authenticated, False otherwise. TYPE: Get the available chart engines. List of chart engines options Get the size of the file cache in a human-readable format. Human-readable file cache size TYPE: Get the size of the Redis cache in a human-readable format. Human-readable Redis cache size TYPE: Requires Redis 7+ Compatibility with core CKAN versions: Install the extension from Building the documentation
CHARTS_FIELDS
for our custom handler, that autogenerate documentation
for chart types fields.
+export CKAN_INI=$PWD/config/ckan.ini
+
ckanext-charts
plugin:ckan.plugins = ... charts_view charts_builder_view ...
+
"},{"location":"#developer-installation","title":"Developer installation","text":"PyPi
with pip install ckanext-charts[pyarrow]
charts_view
to the list of plugins in your CKAN config (ckan.plugins = charts_view charts_builder_view
)ckanext-charts
for development, activate your CKAN virtualenv and do:
"},{"location":"#tests","title":"Tests","text":"git clone https://github.com/DataShades/ckanext-charts.git\ncd ckanext-charts\npip install -e '.[dev]'\n
"},{"location":"#building-the-documentation","title":"Building the documentation","text":"pytest --ckan-ini=test.ini\n
mkdocs
to build the documentation. To build and deploy the documentation, do:CHARTS_FIELDS=1 mkdocs build && mkdocs gh-deploy\n
CHARTS_FIELDS
for our custom handler, that autogenerate documentation for chart types fields.
"},{"location":"#license","title":"License","text":"mkdocs serve -a 127.0.0.1:8001\n
ckanext.charts.cache_strategy
[optional]redis
, file_orc
, file_csv
str
redis
ckanext.charts.redis_cache_ttl
[optional]0
to disable cache.int
3600
ckanext.charts.file_cache_ttl
[optional]0
to disable cache.int
3600
ckanext.charts.enable_cache
[optional]bool
true
ckanext.charts.include_htmx_asset
[optional]bool
true
ckanext.charts.reinit_ckan_js_modules
[optional]bool
false
ckanext.charts.allow_anon_building_charts
[optional]true
.bool
false
ckanext-admin-panel
. The admin panel is a separate extension that provides an alternative admin interface for CKAN. It allows you to manage CKAN settings and other extensions settings through the web interface./admin-panel/charts/config
, but it will be registered only if the ckanext-admin-panel
is installed and enabled.charts_allow_anon_building_charts()
","text":"bool
bool
ckanext/charts/helpers.py
"},{"location":"helpers/#charts.helpers.charts_get_resource_columns","title":"def charts_allow_anon_building_charts() -> bool:\n \"\"\"Check if anonymous users are allowed to build charts.\n\n Returns:\n bool: True if anonymous users are allowed to build charts, False otherwise.\n \"\"\"\n return config.allow_anon_building_charts()\n
charts_get_resource_columns(resource_id)
","text":"resource_id
str
str
str
ckanext/charts/helpers.py
"},{"location":"helpers/#charts.helpers.charts_include_htmx_asset","title":"def charts_get_resource_columns(resource_id: str) -> str:\n \"\"\"Get the columns of the given resource.\n\n Args:\n resource_id: Resource ID\n\n Returns:\n str: JSON string of columns options\n \"\"\"\n fetcher = DatastoreDataFetcher(resource_id)\n\n return json.dumps(\n [{\"id\": col, \"title\": col} for col in fetcher.fetch_data().columns],\n )\n
charts_include_htmx_asset()
","text":"bool
bool
ckanext/charts/helpers.py
"},{"location":"helpers/#charts.helpers.charts_reinit_ckan_js_modules","title":"def charts_include_htmx_asset() -> bool:\n \"\"\"Checks if the HTMX asset should be included.\n\n Returns:\n bool: True if the HTMX asset should be included, False otherwise.\n \"\"\"\n return config.include_htmx_asset()\n
charts_reinit_ckan_js_modules()
","text":"bool
bool
ckanext/charts/helpers.py
"},{"location":"helpers/#charts.helpers.charts_user_is_authenticated","title":"def charts_reinit_ckan_js_modules() -> bool:\n \"\"\"Checks if CKAN JS modules should be reinitialized.\n\n Returns:\n bool: True if CKAN JS modules should be reinitialized, False otherwise.\n \"\"\"\n return config.reinit_ckan_js_modules()\n
charts_user_is_authenticated()
","text":"bool
bool
ckanext/charts/helpers.py
"},{"location":"helpers/#charts.helpers.get_available_chart_engines_options","title":"def charts_user_is_authenticated() -> bool:\n \"\"\"Check if the user is authenticated.\n\n Returns:\n bool: True if the user is authenticated, False otherwise.\n \"\"\"\n return tk.current_user.is_authenticated\n
get_available_chart_engines_options()
","text":"list[dict[str, str]]
ckanext/charts/helpers.py
"},{"location":"helpers/#charts.helpers.get_file_cache_size","title":"def get_available_chart_engines_options() -> list[dict[str, str]]:\n \"\"\"Get the available chart engines.\n\n Returns:\n List of chart engines options\n \"\"\"\n return [{\"value\": engine, \"text\": engine} for engine in get_chart_engines()]\n
get_file_cache_size()
","text":"str
str
ckanext/charts/helpers.py
"},{"location":"helpers/#charts.helpers.get_redis_cache_size","title":"def get_file_cache_size() -> str:\n \"\"\"Get the size of the file cache in a human-readable format.\n\n Returns:\n str: Human-readable file cache size\n \"\"\"\n return utils.printable_file_size(count_file_cache_size())\n
get_redis_cache_size()
","text":"str
str
ckanext/charts/helpers.py
"},{"location":"install/","title":"Installation","text":""},{"location":"install/#requirements","title":"Requirements","text":"def get_redis_cache_size() -> str:\n \"\"\"Get the size of the Redis cache in a human-readable format.\n\n Returns:\n str: Human-readable Redis cache size\n \"\"\"\n return utils.printable_file_size(count_redis_cache_size())\n
PyPI
: pip install ckanext-charts\n
If you want to use ORC
file cache, you have to install the extension with the pyarrow
extra:
pip install ckanext-charts[pyarrow]\n
Enable the view and builder plugins in your CKAN configuration file (e.g. ckan.ini
or production.ini
):
ckan.plugins = ... charts_view charts_builder_view ...\n
The extension requires the following CKAN extensions to be installed and enabled:
ckanext-scheming: We're using the scheming extension to create custom forms for the chart builders.
ckanext-admin-panel (optional): If you want to use the admin configuration page, you need to install and enable this extension. The admin panel is a separate extension that provides an alternative admin interface for CKAN. It allows you to manage CKAN settings and other extensions settings through the web interface and significantly extends the default CKAN admin interface.
ImportError: lxml.html.clean module is now a separate project lxml_html_clean
Install lxml[html_clean]
or lxml_html_clean
directly using pip.
This extension offers two plugins: charts_view
and charts_builder_view
. The first plugin is a standard chart builder designed for system administrators or anyone with permission to edit or create a resource view. Creating a preview using this plugin generates a static chart with saved settings. This chart retains the settings and will always be rendered in the same way.
The charts_builder_view
plugin does not have any special settings during the creation or editing stages. Instead, it renders a chart builder JS widget on a resource page, allowing any user to interact with the resource data and create a chart that meets their needs. In the future, we plan to implement a feature that will allow users to save their charts.
The user chart builder could be restricted to only authenticated users. See the config settings section for more information. In this case, user will be forced to log in to build a chart. After the user logs in, user will be redirected to the chart builder page back.
"},{"location":"utils/","title":"Utility Functions","text":""},{"location":"utils/#charts.utils.build_chart_for_data","title":"build_chart_for_data(settings, data)
","text":"Build chart for the given dataframe and settings.
PARAMETER DESCRIPTIONsettings
Chart settings
TYPE: dict[str, Any]
data
Dataframe with data
TYPE: DataFrame
str | None
Chart config as JSON string
Source code inckanext/charts/utils.py
def build_chart_for_data(settings: dict[str, Any], data: pd.DataFrame) -> str | None:\n \"\"\"Build chart for the given dataframe and settings.\n\n Args:\n settings: Chart settings\n data: Dataframe with data\n\n Returns:\n Chart config as JSON string\n \"\"\"\n return _build_chart(settings, data)\n
"},{"location":"utils/#charts.utils.build_chart_for_resource","title":"build_chart_for_resource(settings, resource_id)
","text":"Build chart for the given resource ID.
Uses a DatastoreDataFetcher to fetch data from the resource.
PARAMETER DESCRIPTIONsettings
Chart settings
TYPE: dict[str, Any]
resource_id
Resource ID
TYPE: str
str | None
str | None: Chart config as JSON string or None if the chart can't be built
Source code inckanext/charts/utils.py
def build_chart_for_resource(settings: dict[str, Any], resource_id: str) -> str | None:\n \"\"\"Build chart for the given resource ID.\n\n Uses a DatastoreDataFetcher to fetch data from the resource.\n\n Args:\n settings: Chart settings\n resource_id: Resource ID\n\n Returns:\n str | None: Chart config as JSON string or None if the chart can't be built\n \"\"\"\n settings.pop(\"__extras\", None)\n\n try:\n df = DatastoreDataFetcher(resource_id).fetch_data()\n except tk.ValidationError:\n return None\n\n return _build_chart(settings, df)\n
"},{"location":"utils/#charts.utils.can_view","title":"can_view(data_dict)
","text":"Check if the resource can be viewed as a chart.
For now, we work only with resources stored with the DataStore.
PARAMETER DESCRIPTIONdata_dict
Resource data dictionary
TYPE: dict[str, Any]
bool
True if the resource can be viewed as a chart, False otherwise
TYPE: bool
ckanext/charts/utils.py
def can_view(data_dict: dict[str, Any]) -> bool:\n \"\"\"Check if the resource can be viewed as a chart.\n\n For now, we work only with resources stored with the DataStore.\n\n Args:\n data_dict: Resource data dictionary\n\n Returns:\n bool: True if the resource can be viewed as a chart, False otherwise\n \"\"\"\n if data_dict[\"resource\"].get(\"datastore_active\"):\n return True\n\n # TODO: Add support for XML, XLS, XLSX, and other formats tabular data?\n # if data_dict[\"resource\"][\"format\"].lower() == \"xml\":\n # return True\n\n return False\n
"},{"location":"utils/#charts.utils.get_chart_form_builder","title":"get_chart_form_builder(engine, chart_type)
","text":"Get form builder for the given engine and chart type.
Source code inckanext/charts/utils.py
def get_chart_form_builder(engine: str, chart_type: str):\n \"\"\"Get form builder for the given engine and chart type.\"\"\"\n builders = get_chart_engines()\n\n if engine not in builders:\n raise NotImplementedError(f\"Engine {engine} is not supported\")\n\n return builders[engine].get_form_for_type(chart_type)\n
"},{"location":"utils/#charts.utils.get_column_options","title":"get_column_options(resource_id)
","text":"Get column options for the given resource.
PARAMETER DESCRIPTIONresource_id
Resource ID
TYPE: str
list[dict[str, str]]
List of column options
Source code inckanext/charts/utils.py
def get_column_options(resource_id: str) -> list[dict[str, str]]:\n \"\"\"Get column options for the given resource.\n\n Args:\n resource_id: Resource ID\n\n Returns:\n List of column options\n \"\"\"\n df = DatastoreDataFetcher(resource_id).fetch_data()\n\n return [{\"text\": col, \"value\": col} for col in df.columns]\n
"},{"location":"utils/#charts.utils.printable_file_size","title":"printable_file_size(size_bytes)
","text":"Convert file size in bytes to human-readable format.
PARAMETER DESCRIPTIONsize_bytes
File size in bytes
TYPE: int
str
Human-readable file size
TYPE: str
Examples:
>>> printable_file_size(123456789)\n'117.7 MB'\n
>>> printable_file_size(7777)\n'7.6 KB'\n
Source code in ckanext/charts/utils.py
def printable_file_size(size_bytes: int) -> str:\n \"\"\"Convert file size in bytes to human-readable format.\n\n Args:\n size_bytes: File size in bytes\n\n Returns:\n str: Human-readable file size\n\n Examples:\n >>> printable_file_size(123456789)\n '117.7 MB'\n\n >>> printable_file_size(7777)\n '7.6 KB'\n \"\"\"\n if size_bytes == 0:\n return \"0 bytes\"\n\n size_name = (\"bytes\", \"KB\", \"MB\", \"GB\", \"TB\")\n i = int(math.floor(math.log(size_bytes, 1024)))\n p = math.pow(1024, i)\n s = round(float(size_bytes) / p, 1)\n\n return f\"{s} {size_name[i]}\"\n
"},{"location":"validators/","title":"Validators","text":""},{"location":"validators/#charts.logic.validators.charts_if_empty_same_as","title":"charts_if_empty_same_as(other_key)
","text":"A custom version of if_empty_same_as validator for charts.
This validator is used to set the value of a field to the value of another field if it is empty or missing.
PARAMETER DESCRIPTIONother_key
The key of the field to copy the value from
TYPE: str
Callable[..., Any]
Callable[..., Any]: The validator function
Source code inckanext/charts/logic/validators.py
def charts_if_empty_same_as(other_key: str) -> Callable[..., Any]:\n \"\"\"A custom version of if_empty_same_as validator for charts.\n\n This validator is used to set the value of a field to the value of another\n field if it is empty or missing.\n\n Args:\n other_key (str): The key of the field to copy the value from\n\n Returns:\n Callable[..., Any]: The validator function\n \"\"\"\n\n def callable(key, data, errors, context):\n value = data.get(key)\n if not value or value is tk.missing:\n try:\n data[key] = data[key[:-1] + (other_key,)]\n except KeyError:\n data[key] = data.get((\"__extras\",), {}).get(other_key, \"\")\n\n return callable\n
"},{"location":"validators/#charts.logic.validators.charts_list_length_validator","title":"charts_list_length_validator(max_length)
","text":"A validator to check the length of a list.
PARAMETER DESCRIPTIONmax_length
The maximum length of the list
TYPE: int
Callable[..., Any]
Callable[..., Any]: The validator function
Source code inckanext/charts/logic/validators.py
def charts_list_length_validator(max_length: int) -> Callable[..., Any]:\n \"\"\"A validator to check the length of a list.\n\n Args:\n max_length (int): The maximum length of the list\n\n Returns:\n Callable[..., Any]: The validator function\n \"\"\"\n def callable(\n key: types.FlattenKey,\n data: types.FlattenDataDict,\n errors: types.FlattenErrorDict,\n context: types.Context,\n ):\n if len(data[key]) > max_length:\n raise tk.Invalid(tk._(\"Length must be less than {0}\").format(max_length))\n\n return callable\n
"},{"location":"validators/#charts.logic.validators.charts_list_to_csv","title":"charts_list_to_csv(data)
","text":"Convert a list of strings to a CSV string.
PARAMETER DESCRIPTIONdata
The data to convert
TYPE: list[str] | str
str
The comma separated string
TYPE: str
ckanext/charts/logic/validators.py
def charts_list_to_csv(data: list[str] | str) -> str:\n \"\"\"Convert a list of strings to a CSV string.\n\n Args:\n data (list[str] | str): The data to convert\n\n Returns:\n str: The comma separated string\n \"\"\"\n if not isinstance(data, list):\n return data\n\n return \", \".join(data)\n
"},{"location":"validators/#charts.logic.validators.charts_strategy_support","title":"charts_strategy_support(strategy)
","text":"Check if the cache strategy is supported.
PARAMETER DESCRIPTIONstrategy
The cache strategy
TYPE: str
str
The cache strategy if it is supported
TYPE: str
Invalid
If the cache strategy is not supported
Source code inckanext/charts/logic/validators.py
def charts_strategy_support(strategy: str) -> str:\n \"\"\"Check if the cache strategy is supported.\n\n Args:\n strategy (str): The cache strategy\n\n Returns:\n str: The cache strategy if it is supported\n\n Raises:\n tk.Invalid: If the cache strategy is not supported\n \"\"\"\n if strategy not in const.SUPPORTED_CACHE_STRATEGIES:\n raise tk.Invalid(tk._(\"Invalid cache strategy\"))\n\n if strategy == const.CACHE_FILE_ORC:\n try:\n from pyarrow import orc as _ # noqa\n except ImportError:\n raise tk.Invalid(\n tk._(\"Can't use File Orc cache strategy. PyArrow is not installed\"),\n ) from None\n\n if not strategy:\n return const.DEFAULT_CACHE_STRATEGY\n\n return strategy\n
"},{"location":"validators/#charts.logic.validators.charts_to_list_if_string","title":"charts_to_list_if_string(value)
","text":"Convert a string to a list.
PARAMETER DESCRIPTIONvalue
The value to convert
TYPE: Any
Any
list[Any]: The value in a list
Source code inckanext/charts/logic/validators.py
def charts_to_list_if_string(value: Any) -> Any:\n \"\"\"Convert a string to a list.\n\n Args:\n value (Any): The value to convert\n\n Returns:\n list[Any]: The value in a list\n \"\"\"\n if isinstance(value, str):\n return [value]\n\n return value\n
"},{"location":"validators/#charts.logic.validators.charts_validate_extras","title":"charts_validate_extras(key, data, errors, context)
","text":"Validate charts settings according to the chart type and engine schema.
PARAMETER DESCRIPTIONkey
The key of the field
TYPE: FlattenKey
data
The data to validate
TYPE: FlattenDataDict
errors
The errors dict
TYPE: FlattenErrorDict
context
The context
TYPE: Context
ckanext/charts/logic/validators.py
def charts_validate_extras(\n key: types.FlattenKey,\n data: types.FlattenDataDict,\n errors: types.FlattenErrorDict,\n context: types.Context,\n):\n \"\"\"Validate charts settings according to the chart type and engine schema.\n\n Args:\n key (types.FlattenKey): The key of the field\n data (types.FlattenDataDict): The data to validate\n errors (types.FlattenErrorDict): The errors dict\n context (types.Context): The context\n \"\"\"\n settings = _extract_setting(data)\n\n if \"engine\" not in settings or \"type\" not in settings:\n builder = DEFAULT_CHART_FORM\n else:\n builder = utils.get_chart_form_builder(settings[\"engine\"], settings[\"type\"])\n\n settings, err = tk.navl_validate(\n settings,\n builder(settings[\"resource_id\"]).get_validation_schema(\n context.get(\"_for_show\", False),\n ),\n {},\n )\n\n # TODO: do we have a better way to handle this? Seems like a hack\n for k, v in settings.items():\n data[(k,)] = v\n\n for k, v in settings.pop(\"__extras\", {}).items():\n data[(k,)] = v\n\n for k, v in err.items():\n errors[(k,)] = v\n
"},{"location":"validators/#charts.logic.validators.float_validator","title":"float_validator(value)
","text":"A validator for decimal numbers.
PARAMETER DESCRIPTIONvalue
The value to validate
TYPE: Any
float
The value as a float
TYPE: float
ckanext/charts/logic/validators.py
def float_validator(value: Any) -> float:\n \"\"\"A validator for decimal numbers.\n\n Args:\n value (Any): The value to validate\n\n Returns:\n float: The value as a float\n \"\"\"\n try:\n return float(value)\n except ValueError:\n raise tk.Invalid(tk._(\"Must be a decimal number\")) from None\n
"},{"location":"caching/","title":"Caching","text":"The extension implement a cache strategy to store the data fetched from the different sources.
There are three cache strategies available:
redis
file_orc
file_csv
.The file cache works by storing the data in an orc
or csv
file in the filesystem. The redis cache stores the data in a Redis database. The cache strategy can be changed at the CKAN configuration level through the admin interface or in a configuration file.
The file-type
cache strategy stores the data in a file in the filesystem. The file cache is stored in the ckanext-charts
directory in the CKAN storage path. The file cache is stored in an orc
or csv
file format.
Using file_orc
cache strategy requires the pyarrow
python library to be installed.
The redis
cache strategy stores the data in a Redis database.
Each redis key has a ckanext-charts:*
prefix and store the data as a CSV string.
You need to have a Redis server running to use the redis
cache strategy.
The cache TTL can be set in the CKAN configuration file. The default value is 3600 seconds (1 hour). The cache TTL can be set to 0
to disable the cache.
The redis
and file-type
cache has separate TTL settings:
redis
cache TTL can be set with the ckanext.charts.redis_cache_ttl
configuration option.file
cache TTL can be set with the ckanext.charts.file_cache_ttl
configuration option.Cache could be disabled by setting ckanext.charts.enable_cache
to false
. In this case the data will be fetched from the source every time the chart is rendered. It could be useful for debugging purposes. But using it in production is not recommended, as it could lead to performance issues.
To implement a custom cache strategy, you need to create a new class that extends the CacheStrategy
class and implement the abstract methods.
See a naive implementation of a memcached cache strategy below:
from io import BytesIO\n\nfrom pymemcache.client import base\nimport pandas as pd\n\nimport ckanext.charts.config as config\nfrom ckanext.charts.cache import CacheStrategy\n\nclass MemcachedCache(CacheStrategy):\n \"\"\"Cache data to Memcached\"\"\"\n\n def __init__(self):\n self.client = base.Client(('localhost', 11211))\n\n def get_data(self, key: str) -> pd.DataFrame | None:\n \"\"\"Return data from cache if exists\"\"\"\n try:\n raw_data = self.client.get(key)\n\n if not raw_data:\n return None\n\n return pd.read_csv(BytesIO(raw_data))\n except Exception:\n log.exception(f\"Failed to get data for key: {key}\")\n return None\n\n def set_data(self, key: str, data: pd.DataFrame):\n \"\"\"Serialize data and save to Memcached\"\"\"\n cache_ttl = config.get_memcached_cache_ttl()\n\n try:\n serialized_data = data.to_csv(index=False).encode('utf-8')\n self.client.set(key, serialized_data, expire=cache_ttl)\n except Exception:\n log.exception(f\"Failed to save data to Memcached for key: {key}\")\n\n def invalidate(self, key: str):\n \"\"\"Invalidate cache by key\"\"\"\n try:\n self.client.delete(key)\n except Exception:\n log.exception(f\"Failed to invalidate cache for key: {key}\")\n
Bases: ABC
Cache strategy interface.
Defines the abstracts methods for cache strategies.
"},{"location":"caching/base/#charts.cache.CacheStrategy.get_data","title":"get_data(key)
abstractmethod
","text":"Return data from cache if exists.
PARAMETER DESCRIPTIONkey
The cache key to retrieve the data.
TYPE: str
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/base/#charts.cache.CacheStrategy.invalidate","title":"invalidate(key)
abstractmethod
","text":"Invalidate cache by key.
PARAMETER DESCRIPTIONkey
The cache key to invalidate.
TYPE: str
set_data(key, data)
abstractmethod
","text":"Store data to cache.
PARAMETER DESCRIPTIONkey
The cache key to store the data.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
FileCache
","text":" Bases: CacheStrategy
Cache data as file.
We store the cached files in a separate folder in the CKAN storage.
"},{"location":"caching/file/#charts.cache.FileCache.generate_unique_consistent_filename","title":"generate_unique_consistent_filename(key)
","text":"Generate unique and consistent filename based on the key.
PARAMETER DESCRIPTIONkey
The cache key to generate the filename.
TYPE: str
str
The filename.
"},{"location":"caching/file/#charts.cache.FileCache.get_data","title":"get_data(key)
","text":"Return data from cache if exists.
PARAMETER DESCRIPTIONkey
The cache key to retrieve the data.
TYPE: str
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCache.invalidate","title":"invalidate(key)
","text":"Remove data from cache.
PARAMETER DESCRIPTIONkey
The cache key to invalidate.
TYPE: str
is_file_cache_expired(file_path)
staticmethod
","text":"Check if file cache is expired.
If TTL is 0 then cache never expires.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
bool
True if file cache is expired, otherwise False.
"},{"location":"caching/file/#charts.cache.FileCache.make_file_path_from_key","title":"make_file_path_from_key(key)
","text":"Generate file path based on the key
PARAMETER DESCRIPTIONkey
The cache key to generate the file path.
TYPE: str
str
The file path.
"},{"location":"caching/file/#charts.cache.FileCache.read_data","title":"read_data(file)
abstractmethod
","text":"Read cached data from a file object.
PARAMETER DESCRIPTIONfile
The file object to read the data.
TYPE: IO
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCache.set_data","title":"set_data(key, data)
","text":"Store data to cache.
PARAMETER DESCRIPTIONkey
The cache key to store the data.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
write_data(file_path, data)
abstractmethod
","text":"Defines how to write data to a file.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
FileCacheORC
","text":" Bases: FileCache
Cache data as ORC file
"},{"location":"caching/file/#charts.cache.FileCacheORC.read_data","title":"read_data(file)
","text":"Read cached data from an ORC file.
PARAMETER DESCRIPTIONfile
The file object to read the data.
TYPE: IO
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCacheORC.write_data","title":"write_data(file_path, data)
","text":"Write data to an ORC file.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
FileCacheCSV
","text":" Bases: FileCache
Cache data as CSV file
"},{"location":"caching/file/#charts.cache.FileCacheCSV.read_data","title":"read_data(file)
","text":"Read cached data from a CSV file.
PARAMETER DESCRIPTIONfile
The file object to read the data.
TYPE: IO
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCacheCSV.write_data","title":"write_data(file_path, data)
","text":"Write data to a CSV file.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
Bases: CacheStrategy
Cache data to Redis as a CSV string
"},{"location":"caching/redis/#charts.cache.RedisCache.get_data","title":"get_data(key)
","text":"Return data from cache if exists.
PARAMETER DESCRIPTIONkey
The cache key to retrieve the data.
TYPE: str
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/redis/#charts.cache.RedisCache.invalidate","title":"invalidate(key)
","text":"Remove data from cache.
PARAMETER DESCRIPTIONkey
The cache key to invalidate.
TYPE: str
set_data(key, data)
","text":"Serialize data and save to Redis.
PARAMETER DESCRIPTIONkey
The cache key to store the data.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
Exception
If failed to save data to Redis.
"},{"location":"engines/","title":"Index","text":"The ckanext-charts
implements supports different chart engines, such as plotly
, observable
and chartjs
.
Each engine consists of two classes - chart builder and form builder. The chart builder is responsible for generating a JSON-string representation of the chart data, that will be passed to a respective JS module, that will render a chart based on the data.
The form builder is responsible for generating a form that allows users to configure the chart from the UI.
Also, you can implement support of a chart library of your choice by creating a custom chart engine. Read more about it here.
"},{"location":"engines/chartjs/","title":"Chartjs","text":"The Chart.JS
chart engine supports the following chart types:
ckanext/charts/chart_builders/chartjs.py
class ChartJsBuilder(BaseChartBuilder):\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [\n ChartJSBarForm,\n ChartJSHorizontalBarForm,\n ChartJSLineForm,\n ChartJSPieForm,\n ChartJSDoughnutForm,\n ChartJSScatterForm,\n ChartJSBubbleForm,\n ChartJSRadarForm,\n ]\n\n def _create_zoom_and_title_options(self, options: dict[str, Any]) -> dict[str, Any]:\n \"\"\"Add zoom and title plugin options to the provided options dictionary\"\"\"\n if \"plugins\" not in options:\n options[\"plugins\"] = {}\n\n options[\"plugins\"].update(\n {\n \"zoom\": {\n \"zoom\": {\n \"wheel\": {\"enabled\": True},\n \"pinch\": {\"enabled\": True},\n \"drag\": {\"enabled\": True},\n \"mode\": \"xy\",\n },\n \"pan\": {\n \"enabled\": True,\n \"modifierKey\": \"shift\",\n \"mode\": \"xy\",\n },\n },\n \"title\": {\n \"display\": True,\n \"position\": \"bottom\",\n },\n },\n )\n return options\n
"},{"location":"engines/chartjs/#bar-chart","title":"Bar chart","text":"The bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. For a horizontal bar chart, use the Horizontal bar chart
chart type.
title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select one or more columns for the Y-axis
Type: List[str]
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The horizontal bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars are plotted horizontally.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select one or more columns for the Y-axis
Type: List[str]
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The line chart is a chart that displays information as a series of data points called 'markers' connected by straight line segments. It is useful for showing trends over time.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select one or more columns for the Y-axis
Type: List[str]
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
invert_x
) Invert the X-axis
Type: bool
invert_y
) Invert the Y-axis
Type: bool
The pie chart is a circular statistical graphic that is divided into slices to illustrate numerical proportions. The arc length of each slice is proportional to the quantity it represents.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
values
) [Required] Type: str
names
) [Required] Type: str
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The doughnut chart is a variant of the pie chart, with a hole in the center. It is useful for showing the relationship of parts to a whole.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
values
) [Required] Type: str
names
) [Required] Type: str
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The scatter plot is a chart that uses Cartesian coordinates to display values for two variables for a set of data. The data points are represented as individual dots.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The bubble chart is a chart that displays data points as bubbles. The size of the bubble represents a third dimension of the data.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
size
) [Required] Select a column for the size
Type: str
The radar chart is a chart that displays multivariate data in the form of a two-dimensional chart of three or more quantitative variables represented on axes starting from the same point. The data points are connected by a line to form a polygon.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
names
) [Required] Type: str
values
) [Required] Select 3 or more different categorical variables (dimensions)
Type: List[str]
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
Implementing support for a new chart engine includes multiple steps and changes in Python, HTML, and JavaScript. Starting from the Python code:
Create a new builder class at ckanext.charts.chart_builder
that inherits from BaseChartBuilder
and implements the get_supported_forms
method. This method must return a list of classes that represent supported chart types forms.
Each form type builder must be connected with a respective chart type builder.
The chart type builder must implement a to_json
method that will return a dumped JSON data, which will be passed to a JS script.
The form type builder must implement a get_form_fields
method that will return a list of all form fields that will be rendered for the user, allowing them to provide all the necessary information for a chart.
Register your chart engine by adding the builder class to get_chart_engines
in ckanext.charts.chart_builder.__init__.py
.
A full example of an implementation of bar
chart for obvervable plot
library.
from __future__ import annotations\n\nimport json\nfrom typing import Any\n\nimport ckanext.charts.exception as exception\nfrom ckanext.charts.chart_builders.base import BaseChartBuilder, BaseChartForm\n\n\nclass ObservableBuilder(BaseChartBuilder):\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [ObservableBarForm]\n\n\nclass ObservableBarBuilder(ObservableBuilder):\n def to_json(self) -> str:\n return json.dumps(\n {\n \"type\": \"bar\",\n \"data\": self.df.to_dict(orient=\"records\"),\n \"settings\": self.settings,\n }\n )\n\n\nclass ObservableBarForm(BaseChartForm):\n name = \"Bar\"\n builder = ObservableBarBuilder\n\n def fill_field(self, choices: list[dict[str, str]]) -> dict[str, str]:\n field = self.color_field(choices)\n field.update({\"field_name\": \"fill\", \"label\": \"Fill\"})\n\n return field\n\n def get_form_fields(self):\n columns = [{\"value\": col, \"label\": col} for col in self.df.columns]\n chart_types = [\n {\"value\": form.name, \"label\": form.name}\n for form in self.builder.get_supported_forms()\n ]\n\n return [\n self.title_field(),\n self.description_field(),\n self.engine_field(),\n self.type_field(chart_types),\n self.x_axis_field(columns),\n self.y_axis_field(columns),\n self.fill_field(columns),\n self.opacity_field(),\n self.limit_field(),\n ]\n
"},{"location":"engines/custom/#vendor-and-custom-js","title":"Vendor and custom JS","text":"Another step is to register JS/CSS vendor libraries of the chart you want to use. Refer to CKAN documentation to read about adding CSS and JavaScript files using Webassets.
You also will need a CKAN JS module, that will be responsible for rendering the Chart. This module will work with the vendor library and will be responsible for rendering the chart in the container.
This module must be registered inside a webassets.yml
as well.
ckan.module(\"charts-render-observable\", function ($, _) {\n \"use strict\";\n\n return {\n options: {\n config: null\n },\n\n initialize: function () {\n $.proxyAll(this, /_/);\n\n if (!this.options.config) {\n console.error(\"No configuration provided\");\n return;\n }\n\n var plot;\n\n switch (this.options.config.type) {\n case \"bar\":\n plot = Plot.barY(this.options.config.data, this.options.config.settings).plot();\n break;\n default:\n return;\n }\n\n this.el[0].replaceChildren(plot);\n }\n };\n });\n
"},{"location":"engines/custom/#html-container","title":"HTML container","text":"And an HTML file, that will provide a proper container and include your JS module with data-module
.
{% asset \"charts/observable\" %}\n\n {% if chart %}\n <div id=\"chart-container\" data-module=\"charts-render-observable\" data-module-config=\"{{ chart }}\"></div>\n {% else %}\n <p class=\"text-muted\">\n {{ _(\"Cannot build chart with current settings\") }}\n </p>\n {% endif %}\n
Note, that we should add {% asset \"charts/observable\" %}
not only here, but in charts_form.html
too.
The reason for having a separate HTML
file and JS
module is that different libraries may require different types of container elements (such as div, canvas, etc.) to initialize or may need additional boilerplate code to build a chart. There's no easy way to abstract this, so you have to implement these things yourself.
The Observable Plot
chart engine supports the following chart types:
ckanext/charts/chart_builders/observable.py
class ObservableBuilder(BaseChartBuilder):\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [\n ObservableBarForm,\n ObservableHoriontalBarForm,\n ObservableLineForm,\n ObservablePieForm,\n ObservableScatterForm,\n ObservableAutoForm,\n ]\n
"},{"location":"engines/observable/#bar-chart","title":"Bar chart","text":"The bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. For a horizontal bar chart, use the Horizontal bar chart
chart type.
title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
fill
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The horizontal bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars are plotted horizontally.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
fill
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The line chart is a chart that displays information as a series of data points called 'markers' connected by straight line segments. It is useful for showing trends over time.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
invert_x
) Invert the X-axis
Type: bool
invert_y
) Invert the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The pie chart is a circular statistical graphic that is divided into slices to illustrate numerical proportions. The arc length of each slice is proportional to the quantity it represents.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
values
) [Required] Type: str
names
) [Required] Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
innerRadius
) Type:
strokeWidth
) Works only if inner radius is lower than 0
Type:
fontSize
) Type:
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
width
) Width of the chart
Type: int
Default: 640
height
) Height of the chart
Type: int
Default: 400
The scatter plot is a chart that uses Cartesian coordinates to display values for two variables for a set of data. The data points are represented as individual dots.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
color
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The auto chart is a chart that automatically selects the best chart type based on the data. It is useful for quickly visualizing data without having to manually select a chart type.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
color
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The Plotly
chart engine supports the following chart types:
Base class for Plotly chart builders.
Defines supported chart types for Plotly engine.
Source code inckanext/charts/chart_builders/plotly.py
class PlotlyBuilder(BaseChartBuilder):\n \"\"\"Base class for Plotly chart builders.\n\n Defines supported chart types for Plotly engine.\n \"\"\"\n\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [\n PlotlyBarForm,\n PlotlyHoriontalBarForm,\n PlotlyPieForm,\n PlotlyLineForm,\n PlotlyScatterForm,\n ]\n
"},{"location":"engines/plotly/#bar-chart","title":"Bar chart","text":"The bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. For a horizontal bar chart, use the Horizontal bar chart
chart type.
title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The horizontal bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars are plotted horizontally.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The line chart is a chart that displays information as a series of data points called 'markers' connected by straight line segments. It is useful for showing trends over time.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The pie chart is a circular statistical graphic that is divided into slices to illustrate numerical proportions. The arc length of each slice is proportional to the quantity it represents.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
values
) [Required] Type: str
names
) [Required] Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The scatter plot is a chart that uses Cartesian coordinates to display values for two variables for a set of data. The data points are represented as individual dots.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
size
) [Required] Select a column for the size
Type: str
size_max
) Type:
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
Fetchers are responsible for fetching data from different sources (DataStore, URL, file system, hardcoded data).
For the current implementation, we're working with resources that are uploaded to the DataStore, so the fetcher will be responsible for fetching the data from the DataStore.
But it might come in handy to have fetchers for other sources, like URL, file system, etc.
"},{"location":"fetchers/#implementing-new-fetchers","title":"Implementing new fetchers","text":"To register new fetchers, you need to create a new class that inherits from DataFetcherStrategy
and implements the fetch_data
and make_cache_key
methods.
The fetch_data
method should return a pandas
DataFrame
object with the data that should be displayed in the chart.
The make_cache_key
method should return a unique string that will be used as a key to store the data in the cache.
See the base class DataFetcherStrategy
for more information.
All fetchers must inherit from the DataFetcherStrategy
class. This class provides the basic structure for fetchers and defines the methods that must be implemented by all fetchers.
fetch_data()
abstractmethod
","text":"This method should implement the data fetch logic.
All the necessary information should be provided in the constructor.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: The fetched data
"},{"location":"fetchers/base/#charts.fetchers.DataFetcherStrategy.get_cached_data","title":"get_cached_data()
","text":"Fetch data from the cache.
RETURNS DESCRIPTIONDataFrame | None
pd.DataFrame | None: The cached data or None if not found
"},{"location":"fetchers/base/#charts.fetchers.DataFetcherStrategy.invalidate_cache","title":"invalidate_cache()
","text":"Invalidate the cache for the data fetcher.
"},{"location":"fetchers/base/#charts.fetchers.DataFetcherStrategy.make_cache_key","title":"make_cache_key()
abstractmethod
","text":"This method should generate a cache key for the fetched data.
Every data fetcher should implement this method to support caching.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
Fetch dataset resource data from the DataStore.
This fetcher is used to fetch data from the DataStore using the resource ID.
"},{"location":"fetchers/datastore/#charts.fetchers.DatastoreDataFetcher.__init__","title":"__init__(resource_id, limit=2000000, cache_strategy=None)
","text":"Initialize the DatastoreDataFetcher.
PARAMETER DESCRIPTIONresource_id
The ID of the resource to fetch data for.
TYPE: str
limit
The maximum number of rows to fetch.
TYPE: int
DEFAULT: 2000000
cache_strategy
The cache strategy to use. If not provided, the configured cache strategy will be used.
TYPE: str
DEFAULT: None
fetch_data()
","text":"Fetch data from the DataStore.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: Data from the DataStore
"},{"location":"fetchers/datastore/#charts.fetchers.DatastoreDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Generate a cache key for the DataStore data fetcher.
Uses the resource ID as the part of a cache key.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
Bases: DataFetcherStrategy
Fetch data from the file system.
This fetcher is used to fetch data from a file on the file system.
Supported formatsCSV
XLSX
XLS
XML
__init__(file_path, file_format='csv', cache_strategy=None)
","text":"Initialize the FileSystemDataFetcher.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
file_format
The format of the file.
TYPE: str
DEFAULT: 'csv'
cache_strategy
The cache strategy to use. If not provided, the configured cache strategy will be used.
TYPE: str
DEFAULT: None
fetch_data()
","text":"Fetch data from the file system.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: Data fetched from the file system
"},{"location":"fetchers/file/#charts.fetchers.FileSystemDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Generate a cache key for the FileSystem data fetcher.
Uses the file path as the part of a cache key.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
Bases: DataFetcherStrategy
Fetch hardcoded data.
This fetcher is used to make a dataframe from hardcoded data, so you can build a chart from it.
"},{"location":"fetchers/hardcode/#charts.fetchers.HardcodedDataFetcher.__init__","title":"__init__(data)
","text":"Initialize the HardcodedDataFetcher.
PARAMETER DESCRIPTIONdata
The hardcoded data.
TYPE: dict[str, list[Any]]
fetch_data()
","text":"Transform arbitrary data into a dataframe.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: The hardcoded data as a dataframe
"},{"location":"fetchers/hardcode/#charts.fetchers.HardcodedDataFetcher.invalidate_cache","title":"invalidate_cache()
","text":"Hardcoded data is not cached
"},{"location":"fetchers/hardcode/#charts.fetchers.HardcodedDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Hardcoded data is not cached
"},{"location":"fetchers/url/","title":"URL Data Fetcher","text":" Bases: DataFetcherStrategy
Fetch data from a URL.
This fetcher is used to fetch data from a URL.
Supported formatsCSV
XLSX
XLS
XML
__init__(url, file_format='csv', timeout=0, cache_strategy=None)
","text":"Initialize the URLDataFetcher.
PARAMETER DESCRIPTIONurl
The URL to fetch data from.
TYPE: str
file_format
The format of the file.
TYPE: str
DEFAULT: 'csv'
timeout
The timeout for the request in seconds.
TYPE: int
DEFAULT: 0
cache_strategy
The cache strategy to use. If not provided, the configured cache strategy will be used.
TYPE: str
DEFAULT: None
fetch_data()
","text":"Fetch data from the URL.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: Data fetched from the URL
"},{"location":"fetchers/url/#charts.fetchers.URLDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Generate a cache key for the URL data fetcher.
Uses the URL as the part of a cache key.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
make_request()
","text":"Make a request to the URL and return the response content.
RETURNS DESCRIPTIONbytes
The response content
TYPE: bytes
DataFetchError
If an error occurs during the request
"}]} \ No newline at end of file +{"config":{"lang":["en"],"separator":"[\\s\\-\\.\\_]+","pipeline":["stopWordFilter"]},"docs":[{"location":"","title":"Home","text":""},{"location":"#ckanext-charts","title":"ckanext-charts","text":"This extension, ckanext-charts, provides additional functionality for working with charts in CKAN. It allows users to create, manage, and visualize charts based on data stored in CKAN datasets.
The extension includes features such as chart creation, chart editing, chart embedding, and chart sharing. It also supports various chart types, including bar charts, line charts, pie charts, and more.
With ckanext-charts, users can easily generate interactive and visually appealing charts to enhance data analysis and presentation in CKAN.
See the documentation for more information.
"},{"location":"#quick-start","title":"Quick start","text":"PyPi
with pip install ckanext-charts[pyarrow]
charts_view
to the list of plugins in your CKAN config (ckan.plugins = charts_view charts_builder_view
)To install ckanext-charts
for development, activate your CKAN virtualenv and do:
git clone https://github.com/DataShades/ckanext-charts.git\ncd ckanext-charts\npip install -e '.[dev]'\n
"},{"location":"#tests","title":"Tests","text":"To run the tests, do:
pytest --ckan-ini=test.ini\n
"},{"location":"#building-the-documentation","title":"Building the documentation","text":"We are using mkdocs
to build the documentation. To build and deploy the documentation, do:
CHARTS_FIELDS=1 mkdocs build && mkdocs gh-deploy\n
We need to set the CHARTS_FIELDS
for our custom handler, that autogenerate documentation for chart types fields.
The CKAN instance will be initialized, because we will call validators and helpers in this code. Therefore, you'll need another environment variable to set the CKAN configuration file path:
export CKAN_INI=$PWD/config/ckan.ini\n
The config file must enable the ckanext-charts
plugin:
ckan.plugins = ... charts_view charts_builder_view ...\n
If you're working on the documentation, you can run the following command to start a live-reloading server without gathering the chart types fields data. It will speed up the process significantly, as we won't need to wait for the CKAN initialization:
mkdocs serve -a 127.0.0.1:8001\n
"},{"location":"#license","title":"License","text":"AGPL
"},{"location":"configuration/","title":"Configuration","text":"Configuration options
There is a number of configuration options available for the extension. You can set them in the CKAN configuration file or using the admin configuration page.
"},{"location":"configuration/#configuration-options","title":"Configuration options","text":""},{"location":"configuration/#cache-strategy","title":"Cache strategy","text":"ckanext.charts.cache_strategy
[optional]
Cache strategy for chart data.
Options: redis
, file_orc
, file_csv
Type: str
Default: redis
ckanext.charts.redis_cache_ttl
[optional]
Time to live for the Redis cache in seconds. Set to 0
to disable cache.
Type: int
Default: 3600
ckanext.charts.file_cache_ttl
[optional]
Time to live for the File cache in seconds. Set to 0
to disable cache.
Type: int
Default: 3600
ckanext.charts.enable_cache
[optional]
Enable cache for the charts.
WarningIf the cache is disabled, the chart data will be fetched from the data source every time the chart is rendered. It could lead to performance issues if the data source is slow or the data is too large.
Type: bool
Default: true
ckanext.charts.include_htmx_asset
[optional]
Include HTMX assets. Could be disabled if another plugins are including it.
Type: bool
Default: true
ckanext.charts.reinit_ckan_js_modules
[optional]
Reinit CKAN JS modules after HTMX swap.
Type: bool
Default: false
ckanext.charts.allow_anon_building_charts
[optional]
By default, only authenticated users can build charts. If you want to allow anonymous users to build charts, set this option to true
.
Type: bool
Default: false
The extension provides an admin configuration page where you can set all the listed configuration options. The admin page available only using an extension ckanext-admin-panel
. The admin panel is a separate extension that provides an alternative admin interface for CKAN. It allows you to manage CKAN settings and other extensions settings through the web interface.
This page could be accessed by the following URL: /admin-panel/charts/config
, but it will be registered only if the ckanext-admin-panel
is installed and enabled.
charts_allow_anon_building_charts()
","text":"Check if anonymous users are allowed to build charts.
RETURNS DESCRIPTIONbool
True if anonymous users are allowed to build charts, False otherwise.
TYPE: bool
ckanext/charts/helpers.py
def charts_allow_anon_building_charts() -> bool:\n \"\"\"Check if anonymous users are allowed to build charts.\n\n Returns:\n bool: True if anonymous users are allowed to build charts, False otherwise.\n \"\"\"\n return config.allow_anon_building_charts()\n
"},{"location":"helpers/#charts.helpers.charts_get_resource_columns","title":"charts_get_resource_columns(resource_id)
","text":"Get the columns of the given resource.
PARAMETER DESCRIPTIONresource_id
Resource ID
TYPE: str
str
JSON string of columns options
TYPE: str
ckanext/charts/helpers.py
def charts_get_resource_columns(resource_id: str) -> str:\n \"\"\"Get the columns of the given resource.\n\n Args:\n resource_id: Resource ID\n\n Returns:\n str: JSON string of columns options\n \"\"\"\n fetcher = DatastoreDataFetcher(resource_id)\n\n return json.dumps(\n [{\"id\": col, \"title\": col} for col in fetcher.fetch_data().columns],\n )\n
"},{"location":"helpers/#charts.helpers.charts_include_htmx_asset","title":"charts_include_htmx_asset()
","text":"Checks if the HTMX asset should be included.
RETURNS DESCRIPTIONbool
True if the HTMX asset should be included, False otherwise.
TYPE: bool
ckanext/charts/helpers.py
def charts_include_htmx_asset() -> bool:\n \"\"\"Checks if the HTMX asset should be included.\n\n Returns:\n bool: True if the HTMX asset should be included, False otherwise.\n \"\"\"\n return config.include_htmx_asset()\n
"},{"location":"helpers/#charts.helpers.charts_reinit_ckan_js_modules","title":"charts_reinit_ckan_js_modules()
","text":"Checks if CKAN JS modules should be reinitialized.
RETURNS DESCRIPTIONbool
True if CKAN JS modules should be reinitialized, False otherwise.
TYPE: bool
ckanext/charts/helpers.py
def charts_reinit_ckan_js_modules() -> bool:\n \"\"\"Checks if CKAN JS modules should be reinitialized.\n\n Returns:\n bool: True if CKAN JS modules should be reinitialized, False otherwise.\n \"\"\"\n return config.reinit_ckan_js_modules()\n
"},{"location":"helpers/#charts.helpers.charts_user_is_authenticated","title":"charts_user_is_authenticated()
","text":"Check if the user is authenticated.
RETURNS DESCRIPTIONbool
True if the user is authenticated, False otherwise.
TYPE: bool
ckanext/charts/helpers.py
def charts_user_is_authenticated() -> bool:\n \"\"\"Check if the user is authenticated.\n\n Returns:\n bool: True if the user is authenticated, False otherwise.\n \"\"\"\n return tk.current_user.is_authenticated\n
"},{"location":"helpers/#charts.helpers.get_available_chart_engines_options","title":"get_available_chart_engines_options()
","text":"Get the available chart engines.
RETURNS DESCRIPTIONlist[dict[str, str]]
List of chart engines options
Source code inckanext/charts/helpers.py
def get_available_chart_engines_options() -> list[dict[str, str]]:\n \"\"\"Get the available chart engines.\n\n Returns:\n List of chart engines options\n \"\"\"\n return [{\"value\": engine, \"text\": engine} for engine in get_chart_engines()]\n
"},{"location":"helpers/#charts.helpers.get_file_cache_size","title":"get_file_cache_size()
","text":"Get the size of the file cache in a human-readable format.
RETURNS DESCRIPTIONstr
Human-readable file cache size
TYPE: str
ckanext/charts/helpers.py
def get_file_cache_size() -> str:\n \"\"\"Get the size of the file cache in a human-readable format.\n\n Returns:\n str: Human-readable file cache size\n \"\"\"\n return utils.printable_file_size(count_file_cache_size())\n
"},{"location":"helpers/#charts.helpers.get_redis_cache_size","title":"get_redis_cache_size()
","text":"Get the size of the Redis cache in a human-readable format.
RETURNS DESCRIPTIONstr
Human-readable Redis cache size
TYPE: str
ckanext/charts/helpers.py
def get_redis_cache_size() -> str:\n \"\"\"Get the size of the Redis cache in a human-readable format.\n\n Returns:\n str: Human-readable Redis cache size\n \"\"\"\n return utils.printable_file_size(count_redis_cache_size())\n
"},{"location":"install/","title":"Installation","text":""},{"location":"install/#requirements","title":"Requirements","text":"Requires Redis 7+
Compatibility with core CKAN versions:
CKAN version Compatible? 2.9 and earlier no 2.10+ yes"},{"location":"install/#installation_1","title":"Installation","text":"Install the extension from PyPI
:
pip install ckanext-charts\n
If you want to use ORC
file cache, you have to install the extension with the pyarrow
extra:
pip install ckanext-charts[pyarrow]\n
Enable the view and builder plugins in your CKAN configuration file (e.g. ckan.ini
or production.ini
):
ckan.plugins = ... charts_view charts_builder_view ...\n
The extension requires the following CKAN extensions to be installed and enabled:
ckanext-scheming: We're using the scheming extension to create custom forms for the chart builders.
ckanext-admin-panel (optional): If you want to use the admin configuration page, you need to install and enable this extension. The admin panel is a separate extension that provides an alternative admin interface for CKAN. It allows you to manage CKAN settings and other extensions settings through the web interface and significantly extends the default CKAN admin interface.
ImportError: lxml.html.clean module is now a separate project lxml_html_clean
Install lxml[html_clean]
or lxml_html_clean
directly using pip.
This extension offers two plugins: charts_view
and charts_builder_view
. The first plugin is a standard chart builder designed for system administrators or anyone with permission to edit or create a resource view. Creating a preview using this plugin generates a static chart with saved settings. This chart retains the settings and will always be rendered in the same way.
The charts_builder_view
plugin does not have any special settings during the creation or editing stages. Instead, it renders a chart builder JS widget on a resource page, allowing any user to interact with the resource data and create a chart that meets their needs. In the future, we plan to implement a feature that will allow users to save their charts.
The user chart builder could be restricted to only authenticated users. See the config settings section for more information. In this case, user will be forced to log in to build a chart. After the user logs in, user will be redirected to the chart builder page back.
"},{"location":"utils/","title":"Utility Functions","text":""},{"location":"utils/#charts.utils.build_chart_for_data","title":"build_chart_for_data(settings, data)
","text":"Build chart for the given dataframe and settings.
PARAMETER DESCRIPTIONsettings
Chart settings
TYPE: dict[str, Any]
data
Dataframe with data
TYPE: DataFrame
str | None
Chart config as JSON string
Source code inckanext/charts/utils.py
def build_chart_for_data(settings: dict[str, Any], data: pd.DataFrame) -> str | None:\n \"\"\"Build chart for the given dataframe and settings.\n\n Args:\n settings: Chart settings\n data: Dataframe with data\n\n Returns:\n Chart config as JSON string\n \"\"\"\n return _build_chart(settings, data)\n
"},{"location":"utils/#charts.utils.build_chart_for_resource","title":"build_chart_for_resource(settings, resource_id)
","text":"Build chart for the given resource ID.
Uses a DatastoreDataFetcher to fetch data from the resource.
PARAMETER DESCRIPTIONsettings
Chart settings
TYPE: dict[str, Any]
resource_id
Resource ID
TYPE: str
str | None
str | None: Chart config as JSON string or None if the chart can't be built
Source code inckanext/charts/utils.py
def build_chart_for_resource(settings: dict[str, Any], resource_id: str) -> str | None:\n \"\"\"Build chart for the given resource ID.\n\n Uses a DatastoreDataFetcher to fetch data from the resource.\n\n Args:\n settings: Chart settings\n resource_id: Resource ID\n\n Returns:\n str | None: Chart config as JSON string or None if the chart can't be built\n \"\"\"\n settings.pop(\"__extras\", None)\n\n try:\n df = DatastoreDataFetcher(resource_id).fetch_data()\n except tk.ValidationError:\n return None\n\n return _build_chart(settings, df)\n
"},{"location":"utils/#charts.utils.can_view","title":"can_view(data_dict)
","text":"Check if the resource can be viewed as a chart.
For now, we work only with resources stored with the DataStore.
PARAMETER DESCRIPTIONdata_dict
Resource data dictionary
TYPE: dict[str, Any]
bool
True if the resource can be viewed as a chart, False otherwise
TYPE: bool
ckanext/charts/utils.py
def can_view(data_dict: dict[str, Any]) -> bool:\n \"\"\"Check if the resource can be viewed as a chart.\n\n For now, we work only with resources stored with the DataStore.\n\n Args:\n data_dict: Resource data dictionary\n\n Returns:\n bool: True if the resource can be viewed as a chart, False otherwise\n \"\"\"\n if data_dict[\"resource\"].get(\"datastore_active\"):\n return True\n\n # TODO: Add support for XML, XLS, XLSX, and other formats tabular data?\n # if data_dict[\"resource\"][\"format\"].lower() == \"xml\":\n # return True\n\n return False\n
"},{"location":"utils/#charts.utils.get_chart_form_builder","title":"get_chart_form_builder(engine, chart_type)
","text":"Get form builder for the given engine and chart type.
Source code inckanext/charts/utils.py
def get_chart_form_builder(engine: str, chart_type: str):\n \"\"\"Get form builder for the given engine and chart type.\"\"\"\n builders = get_chart_engines()\n\n if engine not in builders:\n raise NotImplementedError(f\"Engine {engine} is not supported\")\n\n return builders[engine].get_form_for_type(chart_type)\n
"},{"location":"utils/#charts.utils.get_column_options","title":"get_column_options(resource_id)
","text":"Get column options for the given resource.
PARAMETER DESCRIPTIONresource_id
Resource ID
TYPE: str
list[dict[str, str]]
List of column options
Source code inckanext/charts/utils.py
def get_column_options(resource_id: str) -> list[dict[str, str]]:\n \"\"\"Get column options for the given resource.\n\n Args:\n resource_id: Resource ID\n\n Returns:\n List of column options\n \"\"\"\n df = DatastoreDataFetcher(resource_id).fetch_data()\n\n return [{\"text\": col, \"value\": col} for col in df.columns]\n
"},{"location":"utils/#charts.utils.printable_file_size","title":"printable_file_size(size_bytes)
","text":"Convert file size in bytes to human-readable format.
PARAMETER DESCRIPTIONsize_bytes
File size in bytes
TYPE: int
str
Human-readable file size
TYPE: str
Examples:
>>> printable_file_size(123456789)\n'117.7 MB'\n
>>> printable_file_size(7777)\n'7.6 KB'\n
Source code in ckanext/charts/utils.py
def printable_file_size(size_bytes: int) -> str:\n \"\"\"Convert file size in bytes to human-readable format.\n\n Args:\n size_bytes: File size in bytes\n\n Returns:\n str: Human-readable file size\n\n Examples:\n >>> printable_file_size(123456789)\n '117.7 MB'\n\n >>> printable_file_size(7777)\n '7.6 KB'\n \"\"\"\n if size_bytes == 0:\n return \"0 bytes\"\n\n size_name = (\"bytes\", \"KB\", \"MB\", \"GB\", \"TB\")\n i = int(math.floor(math.log(size_bytes, 1024)))\n p = math.pow(1024, i)\n s = round(float(size_bytes) / p, 1)\n\n return f\"{s} {size_name[i]}\"\n
"},{"location":"validators/","title":"Validators","text":""},{"location":"validators/#charts.logic.validators.charts_if_empty_same_as","title":"charts_if_empty_same_as(other_key)
","text":"A custom version of if_empty_same_as validator for charts.
This validator is used to set the value of a field to the value of another field if it is empty or missing.
PARAMETER DESCRIPTIONother_key
The key of the field to copy the value from
TYPE: str
Callable[..., Any]
Callable[..., Any]: The validator function
Source code inckanext/charts/logic/validators.py
def charts_if_empty_same_as(other_key: str) -> Callable[..., Any]:\n \"\"\"A custom version of if_empty_same_as validator for charts.\n\n This validator is used to set the value of a field to the value of another\n field if it is empty or missing.\n\n Args:\n other_key (str): The key of the field to copy the value from\n\n Returns:\n Callable[..., Any]: The validator function\n \"\"\"\n\n def callable(key, data, errors, context):\n value = data.get(key)\n if not value or value is tk.missing:\n try:\n data[key] = data[key[:-1] + (other_key,)]\n except KeyError:\n data[key] = data.get((\"__extras\",), {}).get(other_key, \"\")\n\n return callable\n
"},{"location":"validators/#charts.logic.validators.charts_list_length_validator","title":"charts_list_length_validator(max_length)
","text":"A validator to check the length of a list.
PARAMETER DESCRIPTIONmax_length
The maximum length of the list
TYPE: int
Callable[..., Any]
Callable[..., Any]: The validator function
Source code inckanext/charts/logic/validators.py
def charts_list_length_validator(max_length: int) -> Callable[..., Any]:\n \"\"\"A validator to check the length of a list.\n\n Args:\n max_length (int): The maximum length of the list\n\n Returns:\n Callable[..., Any]: The validator function\n \"\"\"\n def callable(\n key: types.FlattenKey,\n data: types.FlattenDataDict,\n errors: types.FlattenErrorDict,\n context: types.Context,\n ):\n if len(data[key]) > max_length:\n raise tk.Invalid(tk._(\"Length must be less than {0}\").format(max_length))\n\n return callable\n
"},{"location":"validators/#charts.logic.validators.charts_list_to_csv","title":"charts_list_to_csv(data)
","text":"Convert a list of strings to a CSV string.
PARAMETER DESCRIPTIONdata
The data to convert
TYPE: list[str] | str
str
The comma separated string
TYPE: str
ckanext/charts/logic/validators.py
def charts_list_to_csv(data: list[str] | str) -> str:\n \"\"\"Convert a list of strings to a CSV string.\n\n Args:\n data (list[str] | str): The data to convert\n\n Returns:\n str: The comma separated string\n \"\"\"\n if not isinstance(data, list):\n return data\n\n return \", \".join(data)\n
"},{"location":"validators/#charts.logic.validators.charts_strategy_support","title":"charts_strategy_support(strategy)
","text":"Check if the cache strategy is supported.
PARAMETER DESCRIPTIONstrategy
The cache strategy
TYPE: str
str
The cache strategy if it is supported
TYPE: str
Invalid
If the cache strategy is not supported
Source code inckanext/charts/logic/validators.py
def charts_strategy_support(strategy: str) -> str:\n \"\"\"Check if the cache strategy is supported.\n\n Args:\n strategy (str): The cache strategy\n\n Returns:\n str: The cache strategy if it is supported\n\n Raises:\n tk.Invalid: If the cache strategy is not supported\n \"\"\"\n if strategy not in const.SUPPORTED_CACHE_STRATEGIES:\n raise tk.Invalid(tk._(\"Invalid cache strategy\"))\n\n if strategy == const.CACHE_FILE_ORC:\n try:\n from pyarrow import orc as _ # noqa\n except ImportError:\n raise tk.Invalid(\n tk._(\"Can't use File Orc cache strategy. PyArrow is not installed\"),\n ) from None\n\n if not strategy:\n return const.DEFAULT_CACHE_STRATEGY\n\n return strategy\n
"},{"location":"validators/#charts.logic.validators.charts_to_list_if_string","title":"charts_to_list_if_string(value)
","text":"Convert a string to a list.
PARAMETER DESCRIPTIONvalue
The value to convert
TYPE: Any
Any
list[Any]: The value in a list
Source code inckanext/charts/logic/validators.py
def charts_to_list_if_string(value: Any) -> Any:\n \"\"\"Convert a string to a list.\n\n Args:\n value (Any): The value to convert\n\n Returns:\n list[Any]: The value in a list\n \"\"\"\n if isinstance(value, str):\n return [value]\n\n return value\n
"},{"location":"validators/#charts.logic.validators.charts_validate_extras","title":"charts_validate_extras(key, data, errors, context)
","text":"Validate charts settings according to the chart type and engine schema.
PARAMETER DESCRIPTIONkey
The key of the field
TYPE: FlattenKey
data
The data to validate
TYPE: FlattenDataDict
errors
The errors dict
TYPE: FlattenErrorDict
context
The context
TYPE: Context
ckanext/charts/logic/validators.py
def charts_validate_extras(\n key: types.FlattenKey,\n data: types.FlattenDataDict,\n errors: types.FlattenErrorDict,\n context: types.Context,\n):\n \"\"\"Validate charts settings according to the chart type and engine schema.\n\n Args:\n key (types.FlattenKey): The key of the field\n data (types.FlattenDataDict): The data to validate\n errors (types.FlattenErrorDict): The errors dict\n context (types.Context): The context\n \"\"\"\n settings = _extract_setting(data)\n\n if \"engine\" not in settings or \"type\" not in settings:\n builder = DEFAULT_CHART_FORM\n else:\n builder = utils.get_chart_form_builder(settings[\"engine\"], settings[\"type\"])\n\n settings, err = tk.navl_validate(\n settings,\n builder(settings[\"resource_id\"]).get_validation_schema(\n context.get(\"_for_show\", False),\n ),\n {},\n )\n\n # TODO: do we have a better way to handle this? Seems like a hack\n for k, v in settings.items():\n data[(k,)] = v\n\n for k, v in settings.pop(\"__extras\", {}).items():\n data[(k,)] = v\n\n for k, v in err.items():\n errors[(k,)] = v\n
"},{"location":"validators/#charts.logic.validators.float_validator","title":"float_validator(value)
","text":"A validator for decimal numbers.
PARAMETER DESCRIPTIONvalue
The value to validate
TYPE: Any
float
The value as a float
TYPE: float
ckanext/charts/logic/validators.py
def float_validator(value: Any) -> float:\n \"\"\"A validator for decimal numbers.\n\n Args:\n value (Any): The value to validate\n\n Returns:\n float: The value as a float\n \"\"\"\n try:\n return float(value)\n except ValueError:\n raise tk.Invalid(tk._(\"Must be a decimal number\")) from None\n
"},{"location":"caching/","title":"Caching","text":"The extension implement a cache strategy to store the data fetched from the different sources.
There are three cache strategies available:
redis
file_orc
file_csv
.The file cache works by storing the data in an orc
or csv
file in the filesystem. The redis cache stores the data in a Redis database. The cache strategy can be changed at the CKAN configuration level through the admin interface or in a configuration file.
The file-type
cache strategy stores the data in a file in the filesystem. The file cache is stored in the ckanext-charts
directory in the CKAN storage path. The file cache is stored in an orc
or csv
file format.
Using file_orc
cache strategy requires the pyarrow
python library to be installed.
The redis
cache strategy stores the data in a Redis database.
Each redis key has a ckanext-charts:*
prefix and store the data as a CSV string.
You need to have a Redis server running to use the redis
cache strategy.
The cache TTL can be set in the CKAN configuration file. The default value is 3600 seconds (1 hour). The cache TTL can be set to 0
to disable the cache.
The redis
and file-type
cache has separate TTL settings:
redis
cache TTL can be set with the ckanext.charts.redis_cache_ttl
configuration option.file
cache TTL can be set with the ckanext.charts.file_cache_ttl
configuration option.Cache could be disabled by setting ckanext.charts.enable_cache
to false
. In this case the data will be fetched from the source every time the chart is rendered. It could be useful for debugging purposes. But using it in production is not recommended, as it could lead to performance issues.
To implement a custom cache strategy, you need to create a new class that extends the CacheStrategy
class and implement the abstract methods.
See a naive implementation of a memcached cache strategy below:
from io import BytesIO\n\nfrom pymemcache.client import base\nimport pandas as pd\n\nimport ckanext.charts.config as config\nfrom ckanext.charts.cache import CacheStrategy\n\nclass MemcachedCache(CacheStrategy):\n \"\"\"Cache data to Memcached\"\"\"\n\n def __init__(self):\n self.client = base.Client(('localhost', 11211))\n\n def get_data(self, key: str) -> pd.DataFrame | None:\n \"\"\"Return data from cache if exists\"\"\"\n try:\n raw_data = self.client.get(key)\n\n if not raw_data:\n return None\n\n return pd.read_csv(BytesIO(raw_data))\n except Exception:\n log.exception(f\"Failed to get data for key: {key}\")\n return None\n\n def set_data(self, key: str, data: pd.DataFrame):\n \"\"\"Serialize data and save to Memcached\"\"\"\n cache_ttl = config.get_memcached_cache_ttl()\n\n try:\n serialized_data = data.to_csv(index=False).encode('utf-8')\n self.client.set(key, serialized_data, expire=cache_ttl)\n except Exception:\n log.exception(f\"Failed to save data to Memcached for key: {key}\")\n\n def invalidate(self, key: str):\n \"\"\"Invalidate cache by key\"\"\"\n try:\n self.client.delete(key)\n except Exception:\n log.exception(f\"Failed to invalidate cache for key: {key}\")\n
Bases: ABC
Cache strategy interface.
Defines the abstracts methods for cache strategies.
"},{"location":"caching/base/#charts.cache.CacheStrategy.get_data","title":"get_data(key)
abstractmethod
","text":"Return data from cache if exists.
PARAMETER DESCRIPTIONkey
The cache key to retrieve the data.
TYPE: str
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/base/#charts.cache.CacheStrategy.invalidate","title":"invalidate(key)
abstractmethod
","text":"Invalidate cache by key.
PARAMETER DESCRIPTIONkey
The cache key to invalidate.
TYPE: str
set_data(key, data)
abstractmethod
","text":"Store data to cache.
PARAMETER DESCRIPTIONkey
The cache key to store the data.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
FileCache
","text":" Bases: CacheStrategy
Cache data as file.
We store the cached files in a separate folder in the CKAN storage.
"},{"location":"caching/file/#charts.cache.FileCache.generate_unique_consistent_filename","title":"generate_unique_consistent_filename(key)
","text":"Generate unique and consistent filename based on the key.
PARAMETER DESCRIPTIONkey
The cache key to generate the filename.
TYPE: str
str
The filename.
"},{"location":"caching/file/#charts.cache.FileCache.get_data","title":"get_data(key)
","text":"Return data from cache if exists.
PARAMETER DESCRIPTIONkey
The cache key to retrieve the data.
TYPE: str
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCache.invalidate","title":"invalidate(key)
","text":"Remove data from cache.
PARAMETER DESCRIPTIONkey
The cache key to invalidate.
TYPE: str
is_file_cache_expired(file_path)
staticmethod
","text":"Check if file cache is expired.
If TTL is 0 then cache never expires.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
bool
True if file cache is expired, otherwise False.
"},{"location":"caching/file/#charts.cache.FileCache.make_file_path_from_key","title":"make_file_path_from_key(key)
","text":"Generate file path based on the key
PARAMETER DESCRIPTIONkey
The cache key to generate the file path.
TYPE: str
str
The file path.
"},{"location":"caching/file/#charts.cache.FileCache.read_data","title":"read_data(file)
abstractmethod
","text":"Read cached data from a file object.
PARAMETER DESCRIPTIONfile
The file object to read the data.
TYPE: IO
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCache.set_data","title":"set_data(key, data)
","text":"Store data to cache.
PARAMETER DESCRIPTIONkey
The cache key to store the data.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
write_data(file_path, data)
abstractmethod
","text":"Defines how to write data to a file.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
FileCacheORC
","text":" Bases: FileCache
Cache data as ORC file
"},{"location":"caching/file/#charts.cache.FileCacheORC.read_data","title":"read_data(file)
","text":"Read cached data from an ORC file.
PARAMETER DESCRIPTIONfile
The file object to read the data.
TYPE: IO
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCacheORC.write_data","title":"write_data(file_path, data)
","text":"Write data to an ORC file.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
FileCacheCSV
","text":" Bases: FileCache
Cache data as CSV file
"},{"location":"caching/file/#charts.cache.FileCacheCSV.read_data","title":"read_data(file)
","text":"Read cached data from a CSV file.
PARAMETER DESCRIPTIONfile
The file object to read the data.
TYPE: IO
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/file/#charts.cache.FileCacheCSV.write_data","title":"write_data(file_path, data)
","text":"Write data to a CSV file.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
Bases: CacheStrategy
Cache data to Redis as a CSV string
"},{"location":"caching/redis/#charts.cache.RedisCache.get_data","title":"get_data(key)
","text":"Return data from cache if exists.
PARAMETER DESCRIPTIONkey
The cache key to retrieve the data.
TYPE: str
DataFrame | None
The data if exists, otherwise None.
"},{"location":"caching/redis/#charts.cache.RedisCache.invalidate","title":"invalidate(key)
","text":"Remove data from cache.
PARAMETER DESCRIPTIONkey
The cache key to invalidate.
TYPE: str
set_data(key, data)
","text":"Serialize data and save to Redis.
PARAMETER DESCRIPTIONkey
The cache key to store the data.
TYPE: str
data
The data to be stored.
TYPE: DataFrame
Exception
If failed to save data to Redis.
"},{"location":"engines/","title":"Index","text":"The ckanext-charts
implements supports different chart engines, such as plotly
, observable
and chartjs
.
Each engine consists of two classes - chart builder and form builder. The chart builder is responsible for generating a JSON-string representation of the chart data, that will be passed to a respective JS module, that will render a chart based on the data.
The form builder is responsible for generating a form that allows users to configure the chart from the UI.
Also, you can implement support of a chart library of your choice by creating a custom chart engine. Read more about it here.
"},{"location":"engines/chartjs/","title":"Chartjs","text":"The Chart.JS
chart engine supports the following chart types:
ckanext/charts/chart_builders/chartjs.py
class ChartJsBuilder(BaseChartBuilder):\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [\n ChartJSBarForm,\n ChartJSHorizontalBarForm,\n ChartJSLineForm,\n ChartJSPieForm,\n ChartJSDoughnutForm,\n ChartJSScatterForm,\n ChartJSBubbleForm,\n ChartJSRadarForm,\n ]\n\n def _create_zoom_and_title_options(self, options: dict[str, Any]) -> dict[str, Any]:\n \"\"\"Add zoom and title plugin options to the provided options dictionary\"\"\"\n if \"plugins\" not in options:\n options[\"plugins\"] = {}\n\n options[\"plugins\"].update(\n {\n \"zoom\": {\n \"zoom\": {\n \"wheel\": {\"enabled\": True},\n \"pinch\": {\"enabled\": True},\n \"drag\": {\"enabled\": True},\n \"mode\": \"xy\",\n },\n \"pan\": {\n \"enabled\": True,\n \"modifierKey\": \"shift\",\n \"mode\": \"xy\",\n },\n },\n \"title\": {\n \"display\": True,\n \"position\": \"bottom\",\n },\n },\n )\n return options\n
"},{"location":"engines/chartjs/#bar-chart","title":"Bar chart","text":"The bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. For a horizontal bar chart, use the Horizontal bar chart
chart type.
title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select one or more columns for the Y-axis
Type: List[str]
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The horizontal bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars are plotted horizontally.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select one or more columns for the Y-axis
Type: List[str]
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The line chart is a chart that displays information as a series of data points called 'markers' connected by straight line segments. It is useful for showing trends over time.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select one or more columns for the Y-axis
Type: List[str]
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
invert_x
) Invert the X-axis
Type: bool
invert_y
) Invert the Y-axis
Type: bool
The pie chart is a circular statistical graphic that is divided into slices to illustrate numerical proportions. The arc length of each slice is proportional to the quantity it represents.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
values
) [Required] Type: str
names
) [Required] Type: str
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The doughnut chart is a variant of the pie chart, with a hole in the center. It is useful for showing the relationship of parts to a whole.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
values
) [Required] Type: str
names
) [Required] Type: str
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The scatter plot is a chart that uses Cartesian coordinates to display values for two variables for a set of data. The data points are represented as individual dots.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The bubble chart is a chart that displays data points as bubbles. The size of the bubble represents a third dimension of the data.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
size
) [Required] Select a column for the size
Type: str
The radar chart is a chart that displays multivariate data in the form of a two-dimensional chart of three or more quantitative variables represented on axes starting from the same point. The data points are connected by a line to form a polygon.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Doughnut
, Scatter
, Bubble
, Radar
names
) [Required] Type: str
values
) [Required] Select 3 or more different categorical variables (dimensions)
Type: List[str]
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
Implementing support for a new chart engine includes multiple steps and changes in Python, HTML, and JavaScript. Starting from the Python code:
Create a new builder class at ckanext.charts.chart_builder
that inherits from BaseChartBuilder
and implements the get_supported_forms
method. This method must return a list of classes that represent supported chart types forms.
Each form type builder must be connected with a respective chart type builder.
The chart type builder must implement a to_json
method that will return a dumped JSON data, which will be passed to a JS script.
The form type builder must implement a get_form_fields
method that will return a list of all form fields that will be rendered for the user, allowing them to provide all the necessary information for a chart.
Register your chart engine by adding the builder class to get_chart_engines
in ckanext.charts.chart_builder.__init__.py
.
A full example of an implementation of bar
chart for obvervable plot
library.
from __future__ import annotations\n\nimport json\nfrom typing import Any\n\nimport ckanext.charts.exception as exception\nfrom ckanext.charts.chart_builders.base import BaseChartBuilder, BaseChartForm\n\n\nclass ObservableBuilder(BaseChartBuilder):\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [ObservableBarForm]\n\n\nclass ObservableBarBuilder(ObservableBuilder):\n def to_json(self) -> str:\n return json.dumps(\n {\n \"type\": \"bar\",\n \"data\": self.df.to_dict(orient=\"records\"),\n \"settings\": self.settings,\n }\n )\n\n\nclass ObservableBarForm(BaseChartForm):\n name = \"Bar\"\n builder = ObservableBarBuilder\n\n def fill_field(self, choices: list[dict[str, str]]) -> dict[str, str]:\n field = self.color_field(choices)\n field.update({\"field_name\": \"fill\", \"label\": \"Fill\"})\n\n return field\n\n def get_form_fields(self):\n columns = [{\"value\": col, \"label\": col} for col in self.df.columns]\n chart_types = [\n {\"value\": form.name, \"label\": form.name}\n for form in self.builder.get_supported_forms()\n ]\n\n return [\n self.title_field(),\n self.description_field(),\n self.engine_field(),\n self.type_field(chart_types),\n self.x_axis_field(columns),\n self.y_axis_field(columns),\n self.fill_field(columns),\n self.opacity_field(),\n self.limit_field(),\n ]\n
"},{"location":"engines/custom/#vendor-and-custom-js","title":"Vendor and custom JS","text":"Another step is to register JS/CSS vendor libraries of the chart you want to use. Refer to CKAN documentation to read about adding CSS and JavaScript files using Webassets.
You also will need a CKAN JS module, that will be responsible for rendering the Chart. This module will work with the vendor library and will be responsible for rendering the chart in the container.
This module must be registered inside a webassets.yml
as well.
ckan.module(\"charts-render-observable\", function ($, _) {\n \"use strict\";\n\n return {\n options: {\n config: null\n },\n\n initialize: function () {\n $.proxyAll(this, /_/);\n\n if (!this.options.config) {\n console.error(\"No configuration provided\");\n return;\n }\n\n var plot;\n\n switch (this.options.config.type) {\n case \"bar\":\n plot = Plot.barY(this.options.config.data, this.options.config.settings).plot();\n break;\n default:\n return;\n }\n\n this.el[0].replaceChildren(plot);\n }\n };\n });\n
"},{"location":"engines/custom/#html-container","title":"HTML container","text":"And an HTML file, that will provide a proper container and include your JS module with data-module
.
{% asset \"charts/observable\" %}\n\n {% if chart %}\n <div id=\"chart-container\" data-module=\"charts-render-observable\" data-module-config=\"{{ chart }}\"></div>\n {% else %}\n <p class=\"text-muted\">\n {{ _(\"Cannot build chart with current settings\") }}\n </p>\n {% endif %}\n
Note, that we should add {% asset \"charts/observable\" %}
not only here, but in charts_form.html
too.
The reason for having a separate HTML
file and JS
module is that different libraries may require different types of container elements (such as div, canvas, etc.) to initialize or may need additional boilerplate code to build a chart. There's no easy way to abstract this, so you have to implement these things yourself.
The Observable Plot
chart engine supports the following chart types:
ckanext/charts/chart_builders/observable.py
class ObservableBuilder(BaseChartBuilder):\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [\n ObservableBarForm,\n ObservableHoriontalBarForm,\n ObservableLineForm,\n ObservablePieForm,\n ObservableScatterForm,\n ObservableAutoForm,\n ]\n
"},{"location":"engines/observable/#bar-chart","title":"Bar chart","text":"The bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. For a horizontal bar chart, use the Horizontal bar chart
chart type.
title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
fill
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The horizontal bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars are plotted horizontally.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
fill
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The line chart is a chart that displays information as a series of data points called 'markers' connected by straight line segments. It is useful for showing trends over time.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
invert_x
) Invert the X-axis
Type: bool
invert_y
) Invert the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The pie chart is a circular statistical graphic that is divided into slices to illustrate numerical proportions. The arc length of each slice is proportional to the quantity it represents.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
values
) [Required] Type: str
names
) [Required] Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
innerRadius
) Type:
strokeWidth
) Works only if inner radius is lower than 0
Type:
fontSize
) Type:
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
width
) Width of the chart
Type: int
Default: 640
height
) Height of the chart
Type: int
Default: 400
The scatter plot is a chart that uses Cartesian coordinates to display values for two variables for a set of data. The data points are represented as individual dots.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
color
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The auto chart is a chart that automatically selects the best chart type based on the data. It is useful for quickly visualizing data without having to manually select a chart type.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Line
, Pie
, Scatter
, Auto
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
color
) Select a column for the color
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The Plotly
chart engine supports the following chart types:
Base class for Plotly chart builders.
Defines supported chart types for Plotly engine.
Source code inckanext/charts/chart_builders/plotly.py
class PlotlyBuilder(BaseChartBuilder):\n \"\"\"Base class for Plotly chart builders.\n\n Defines supported chart types for Plotly engine.\n \"\"\"\n\n @classmethod\n def get_supported_forms(cls) -> list[type[Any]]:\n return [\n PlotlyBarForm,\n PlotlyHoriontalBarForm,\n PlotlyPieForm,\n PlotlyLineForm,\n PlotlyScatterForm,\n ]\n
"},{"location":"engines/plotly/#bar-chart","title":"Bar chart","text":"The bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars can be plotted vertically or horizontally. For a horizontal bar chart, use the Horizontal bar chart
chart type.
title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The horizontal bar chart is a chart with rectangular bars with lengths proportional to the values that they represent. The bars are plotted horizontally.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The line chart is a chart that displays information as a series of data points called 'markers' connected by straight line segments. It is useful for showing trends over time.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The pie chart is a circular statistical graphic that is divided into slices to illustrate numerical proportions. The arc length of each slice is proportional to the quantity it represents.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
values
) [Required] Type: str
names
) [Required] Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
The scatter plot is a chart that uses Cartesian coordinates to display values for two variables for a set of data. The data points are represented as individual dots.
Title (title
) Title of the chart view
Type: str
description
) Description of the chart view
Type: str
engine
) [Required] Select the chart engine to use
Type: str
Default: plotly
Choices: plotly
, observable
, chartjs
type
) [Required] Select the type of the chart, e.g. Line, Bar, Scatter, etc.
Type: str
Default: Line
Choices: Bar
, Horizontal Bar
, Pie
, Line
, Scatter
x
) [Required] Select a column for the X-axes
Type: str
y
) [Required] Select a column for the Y-axis
Type: str
log_x
) Use log scale for the X-axis
Type: bool
log_y
) Use log scale for the Y-axis
Type: bool
sort_x
) Sort the X-axis values
Type: bool
sort_y
) Sort the Y-axis values
Type: bool
skip_null_values
) Entries of the data with missing values will not be graphed or will be skipped
Type: bool
size
) [Required] Select a column for the size
Type: str
size_max
) Type:
limit
) Limit the number of rows to show in the chart
Type: int
Default: 100
color
) Select a column for the color
Type: str
animation_frame
) Select a column for the animation frame
Type: str
opacity
) Opacity level of the chart
Type: float
Default: 1
Fetchers are responsible for fetching data from different sources (DataStore, URL, file system, hardcoded data).
For the current implementation, we're working with resources that are uploaded to the DataStore, so the fetcher will be responsible for fetching the data from the DataStore.
But it might come in handy to have fetchers for other sources, like URL, file system, etc.
"},{"location":"fetchers/#implementing-new-fetchers","title":"Implementing new fetchers","text":"To register new fetchers, you need to create a new class that inherits from DataFetcherStrategy
and implements the fetch_data
and make_cache_key
methods.
The fetch_data
method should return a pandas
DataFrame
object with the data that should be displayed in the chart.
The make_cache_key
method should return a unique string that will be used as a key to store the data in the cache.
See the base class DataFetcherStrategy
for more information.
All fetchers must inherit from the DataFetcherStrategy
class. This class provides the basic structure for fetchers and defines the methods that must be implemented by all fetchers.
fetch_data()
abstractmethod
","text":"This method should implement the data fetch logic.
All the necessary information should be provided in the constructor.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: The fetched data
"},{"location":"fetchers/base/#charts.fetchers.DataFetcherStrategy.get_cached_data","title":"get_cached_data()
","text":"Fetch data from the cache.
RETURNS DESCRIPTIONDataFrame | None
pd.DataFrame | None: The cached data or None if not found
"},{"location":"fetchers/base/#charts.fetchers.DataFetcherStrategy.invalidate_cache","title":"invalidate_cache()
","text":"Invalidate the cache for the data fetcher.
"},{"location":"fetchers/base/#charts.fetchers.DataFetcherStrategy.make_cache_key","title":"make_cache_key()
abstractmethod
","text":"This method should generate a cache key for the fetched data.
Every data fetcher should implement this method to support caching.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
Fetch dataset resource data from the DataStore.
This fetcher is used to fetch data from the DataStore using the resource ID.
"},{"location":"fetchers/datastore/#charts.fetchers.DatastoreDataFetcher.__init__","title":"__init__(resource_id, limit=2000000, cache_strategy=None)
","text":"Initialize the DatastoreDataFetcher.
PARAMETER DESCRIPTIONresource_id
The ID of the resource to fetch data for.
TYPE: str
limit
The maximum number of rows to fetch.
TYPE: int
DEFAULT: 2000000
cache_strategy
The cache strategy to use. If not provided, the configured cache strategy will be used.
TYPE: str
DEFAULT: None
fetch_data()
","text":"Fetch data from the DataStore.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: Data from the DataStore
"},{"location":"fetchers/datastore/#charts.fetchers.DatastoreDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Generate a cache key for the DataStore data fetcher.
Uses the resource ID as the part of a cache key.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
Bases: DataFetcherStrategy
Fetch data from the file system.
This fetcher is used to fetch data from a file on the file system.
Supported formatsCSV
XLSX
XLS
XML
__init__(file_path, file_format='csv', cache_strategy=None)
","text":"Initialize the FileSystemDataFetcher.
PARAMETER DESCRIPTIONfile_path
The path to the file.
TYPE: str
file_format
The format of the file.
TYPE: str
DEFAULT: 'csv'
cache_strategy
The cache strategy to use. If not provided, the configured cache strategy will be used.
TYPE: str
DEFAULT: None
fetch_data()
","text":"Fetch data from the file system.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: Data fetched from the file system
"},{"location":"fetchers/file/#charts.fetchers.FileSystemDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Generate a cache key for the FileSystem data fetcher.
Uses the file path as the part of a cache key.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
Bases: DataFetcherStrategy
Fetch hardcoded data.
This fetcher is used to make a dataframe from hardcoded data, so you can build a chart from it.
"},{"location":"fetchers/hardcode/#charts.fetchers.HardcodedDataFetcher.__init__","title":"__init__(data)
","text":"Initialize the HardcodedDataFetcher.
PARAMETER DESCRIPTIONdata
The hardcoded data.
TYPE: dict[str, list[Any]]
fetch_data()
","text":"Transform arbitrary data into a dataframe.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: The hardcoded data as a dataframe
"},{"location":"fetchers/hardcode/#charts.fetchers.HardcodedDataFetcher.invalidate_cache","title":"invalidate_cache()
","text":"Hardcoded data is not cached
"},{"location":"fetchers/hardcode/#charts.fetchers.HardcodedDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Hardcoded data is not cached
"},{"location":"fetchers/url/","title":"URL Data Fetcher","text":" Bases: DataFetcherStrategy
Fetch data from a URL.
This fetcher is used to fetch data from a URL.
Supported formatsCSV
XLSX
XLS
XML
__init__(url, file_format='csv', timeout=0, cache_strategy=None)
","text":"Initialize the URLDataFetcher.
PARAMETER DESCRIPTIONurl
The URL to fetch data from.
TYPE: str
file_format
The format of the file.
TYPE: str
DEFAULT: 'csv'
timeout
The timeout for the request in seconds.
TYPE: int
DEFAULT: 0
cache_strategy
The cache strategy to use. If not provided, the configured cache strategy will be used.
TYPE: str
DEFAULT: None
fetch_data()
","text":"Fetch data from the URL.
RETURNS DESCRIPTIONDataFrame
pd.DataFrame: Data fetched from the URL
"},{"location":"fetchers/url/#charts.fetchers.URLDataFetcher.make_cache_key","title":"make_cache_key()
","text":"Generate a cache key for the URL data fetcher.
Uses the URL as the part of a cache key.
RETURNS DESCRIPTIONstr
The cache key
TYPE: str
make_request()
","text":"Make a request to the URL and return the response content.
RETURNS DESCRIPTIONbytes
The response content
TYPE: bytes
DataFetchError
If an error occurs during the request
"}]} \ No newline at end of file