Documentation for importing packed files

[alexiswl]

Hello,

Been playing around with how to import a packed cwl json file as a CWL parser object.

Here are my steps so far

Setup

# Imports
from pathlib import Path
import json
import sys

# Set path
cwl_file_path = Path("/path/to/cwl.packed.json")

# Load file as dict
# Read in the cwl file from a json
with open(cwl_file_path, "r") as cwl_h:
    cwl_file_dict = json.load(cwl_h)
    

# Conditional import based on cwl version
if 'cwlVersion' not in list(cwl_file_dict.keys()):
    print("Error - could not get the cwlVersion")
    sys.exit(1)
# Import parser based on CWL Version
if cwl_file_dict['cwlVersion'] == 'v1.0':
    from cwl_utils import parser_v1_0 as parser
elif cwl_file_dict['cwlVersion'] == 'v1.1':
    from cwl_utils import parser_v1_1 as parser
elif cwl_file_dict['cwlVersion'] == 'v1.2':
    from cwl_utils import parser_v1_2 as parser
else:
    print("Version error. Did not recognise {} as a CWL version".format(yaml_obj["CWLVersion"]))
    sys.exit(1)

First attempt:

Use the load document feature

parser.load_document(cwl_file_dict, cwl_file_path.absolute().as_uri()) 

SchemaSaladException: Cannot load $import without fileuri

Second attempt

Convert to string then load

parser.load_document_by_string(json.dumps(cwl_file_dict), cwl_file_path.absolute().as_uri())

ValidationException: - tried _RecordLoader but
  Expected a dict
- tried _RecordLoader but
  Expected a dict
...

Third attempt

Convert to yaml then load

# We need to import the ruamel yaml class
from ruamel import yaml
# Dump our dict to a yaml string
cwl_yaml_dump = yaml.round_trip_dump(cwl_file_dict, Dumper=yaml.RoundTripDumper)
# Load yaml
cwl_yaml_load = yaml.round_trip_load(cwl_yaml_dump, preserve_quotes=True)
# Import 
parser.load_document_by_yaml(cwl_yaml_load, cwl_file_path.absolute().as_uri())

ValidationException: - tried _RecordLoader but
  Expected a dict
- tried _RecordLoader but
  Expected a dict
...

Fourth attempt

Convert just graph to yaml then load

# We need to import the ruamel yaml class
from ruamel import yaml
# Dump our dict to a yaml string
cwl_yaml_dump = yaml.round_trip_dump(cwl_file_dict['$graph'], Dumper=yaml.RoundTripDumper)
# Load yaml
cwl_yaml_load = yaml.round_trip_load(cwl_yaml_dump, preserve_quotes=True)
# Import 
parser.load_document_by_yaml(cwl_yaml_load, cwl_file_path.absolute().as_uri())

ValidationException: - tried _RecordLoader but
  Expected a dict
- tried _RecordLoader but
  Expected a dict
...

Is this due to my workflow being a little bit too complicated for the parser and using record schemas?

[mr-c]

Hey @alexiswl ; can you put an example packed workflow that exhibits this issue on https://gist.github.com/ or similar and drop the link here?

[alexiswl]

https://gist.github.com/alexiswl/5dd2bf9639f1b539a8c2dd4170f96ea7

[mr-c]

@alexiswl FYI, that file has ids in its custom types, that is not formally part of the CWL standard: https://www.commonwl.org/v1.2/CommandLineTool.html#CommandInputRecordSchema

[alexiswl]

Hi @mr-c, do you know why this might be? The raw yaml is now publicly accessible at https://github.com/umccr/cwl-ica/blob/main/workflows/bcl-conversion/3.7.5/bcl-conversion__3.7.5.cwl

None of the schemas present have the id attribute in them either:

• fastq-list-row: https://github.com/umccr/cwl-ica/blob/main/schemas/fastq-list-row/1.0.0/fastq-list-row__1.0.0.yaml
• settings-by-samples: https://github.com/umccr/cwl-ica/blob/main/schemas/settings-by-samples/1.0.0/settings-by-samples__1.0.0.yaml

At the moment, in order to import these workflows that contain schemas through the CWL parser, I have to first import the schema object and then manually append the schema object to the namespace.

See:
https://github.com/umccr/cwl-ica/blob/main/src/classes/cwl.py#L135-L154

For packed cwl files this would be a little more difficult for I need to first find the SchemaDefRequirement inside the graph and add them to the $namespaces attribute of the graph.

I guess something like so would be a possible way to grab the schemas required for the workflow.

$ cwltool --pack bcl-conversion__3.7.5.cwl | \
jq --raw-output '.["$graph"][-1].requirements[] | select(.class=="SchemaDefRequirement") | .types[] | .["$import"]'

#settings-by-samples__1.0.0.yaml
#fastq-list-row__1.0.0.yaml

Where the jq component of this would be done in python.

Still, it nonetheless seems quite hacky that this is a requirement.

[mr-c]

@alexiswl As you can see, your helpful example has launched many fixed to cwltool --pack, the code in schema_salad that produces the parsers, and the schema of the CWL standards themselves (!).

Ultimately (when all is done, merged, and released) the answer to your question will be "Load the packed document like any other." :-)

FYI, here is my variation on your testing script

"""
Import a cwl file as a parser object
"""

import sys
from pathlib import Path

from schema_salad.utils import yaml_no_ts 
# ^^ requires schema_salad >= 8.2
# does preserve_quotes=True and more

# Set path
cwl_file_path = Path(sys.argv[1])

# Load file as yaml dict
# Read in the cwl file from a json/yaml
with open(cwl_file_path, "r") as cwl_h:
    cwl_file_yaml = yaml_no_ts().load(cwl_h)

# Conditional import based on cwl version
if 'cwlVersion' not in cwl_file_yaml:
    print("Error - could not get the cwlVersion")
    sys.exit(1)
# Import parser based on CWL Version
if cwl_file_yaml['cwlVersion'] == 'v1.0':
    from cwl_utils import parser_v1_0 as parser
elif cwl_file_yaml['cwlVersion'] == 'v1.1':
    from cwl_utils import parser_v1_1 as parser
elif cwl_file_yaml['cwlVersion'] == 'v1.2':
    from cwl_utils import parser_v1_2 as parser
else:
    print("Version error. Did not recognise {} as a CWL version".format(yaml_obj["CWLVersion"]))
    sys.exit(1)

doc = parser.load_document_by_yaml(cwl_file_yaml, cwl_file_path.absolute().as_uri())