Support CLI arguments for cfn init

src/rpdk/core/init.py

@@ -2,13 +2,12 @@
 """
 import logging
 import re
-from argparse import SUPPRESS
 from functools import wraps
 
 from colorama import Fore, Style
 
 from .exceptions import WizardAbortError, WizardValidationError
-from .plugin_registry import PLUGIN_CHOICES
+from .plugin_registry import get_plugin_choices
 from .project import Project
 
 LOG = logging.getLogger(__name__)
@@ -42,7 +41,7 @@ def validate_type_name(value):
         return value
     LOG.debug("'%s' did not match '%s'", value, TYPE_NAME_REGEX)
     raise WizardValidationError(
-        "Please enter a value matching '{}'".format(TYPE_NAME_REGEX)
+        "Please enter a resource type name matching '{}'".format(TYPE_NAME_REGEX)
     )
 
 
@@ -77,7 +76,7 @@ def __call__(self, value):
 
 
 validate_plugin_choice = ValidatePluginChoice(  # pylint: disable=invalid-name
-    PLUGIN_CHOICES
+    get_plugin_choices()
 )
 
 
@@ -139,10 +138,26 @@ def init(args):
 
     check_for_existing_project(project)
 
-    type_name = input_typename()
+    if args.type_name:
+        try:
+            type_name = validate_type_name(args.type_name)
+        except WizardValidationError as error:
+            print(Style.BRIGHT, Fore.RED, str(error), Style.RESET_ALL, sep="")
+            type_name = input_typename()
+    else:
+        type_name = input_typename()
+
     if args.language:
-        language = args.language
-        LOG.warning("Language plugin '%s' selected non-interactively", language)
+        language = args.language.lower()
+        if language not in get_plugin_choices():
+            print(
+                Style.BRIGHT,
+                Fore.RED,
+                "The plugin for {} is not installed.".format(language),
+                Style.RESET_ALL,
+                sep="",
+            )
+            language = input_language()
     else:
         language = input_language()
 
@@ -172,7 +187,18 @@ def setup_subparser(subparsers, parents):
     parser.set_defaults(command=ignore_abort(init))
 
     parser.add_argument(
-        "--force", action="store_true", help="Force files to be overwritten."
+        "--force",
+        action="store_true",
+        help="Force files to be overwritten.",
+    )
+
+    parser.add_argument(
+        "--language",
+        help="""Select a language for code generation.
+            The language plugin needs to be installed.""",
+    )
+
+    parser.add_argument(
+        "--type-name",
+        help="Selects the name of the resource type.",
     )
-    # this is mainly for CI, so suppress it to keep it simple
-    parser.add_argument("--language", help=SUPPRESS)

src/rpdk/core/plugin_registry.py

@@ -8,5 +8,12 @@
 PLUGIN_CHOICES = sorted(PLUGIN_REGISTRY.keys())
 
 
+def get_plugin_choices():
+    return [
+        entry_point.name
+        for entry_point in pkg_resources.iter_entry_points("rpdk.v1.languages")
+    ]
+
+
 def load_plugin(language):
     return PLUGIN_REGISTRY[language]()()

tests/test_init.py

@@ -1,6 +1,7 @@
 from pathlib import Path
 from unittest.mock import ANY, Mock, PropertyMock, patch
 
+import pkg_resources
 import pytest
 
 from rpdk.core.exceptions import WizardAbortError, WizardValidationError
@@ -21,13 +22,25 @@
 ERROR = "TUJFEL"
 
 
-def test_init_method_interactive_language():
+def add_dummy_language_plugin():
+    distribution = pkg_resources.Distribution(__file__)
+    entry_point = pkg_resources.EntryPoint.parse(
+        "dummy = rpdk.dummy:DummyLanguagePlugin", dist=distribution
+    )
+    distribution._ep_map = {  # pylint: disable=protected-access
+        "rpdk.v1.languages": {"dummy": entry_point}
+    }
+    pkg_resources.working_set.add(distribution)
+
+
+def test_init_method_interactive():
     type_name = object()
     language = object()
 
-    args = Mock(spec_set=["force", "language"])
+    args = Mock(spec_set=["force", "language", "type_name"])
     args.force = False
     args.language = None
+    args.type_name = None
 
     mock_project = Mock(spec=Project)
     mock_project.load_settings.side_effect = FileNotFoundError
@@ -49,12 +62,42 @@ def test_init_method_interactive_language():
     mock_project.generate.assert_called_once_with()
 
 
-def test_init_method_noninteractive_language():
+def test_init_method_noninteractive():
+    add_dummy_language_plugin()
+
+    args = Mock(spec_set=["force", "language", "type_name"])
+    args.force = False
+    args.language = "dummy"
+    args.type_name = "Test::Test::Test"
+
+    mock_project = Mock(spec=Project)
+    mock_project.load_settings.side_effect = FileNotFoundError
+    mock_project.settings_path = ""
+    mock_project.root = Path(".")
+
+    patch_project = patch("rpdk.core.init.Project", return_value=mock_project)
+    patch_tn = patch("rpdk.core.init.input_typename")
+    patch_l = patch("rpdk.core.init.input_language")
+
+    with patch_project, patch_tn as mock_tn, patch_l as mock_l:
+        init(args)
+
+    mock_tn.assert_not_called()
+    mock_l.assert_not_called()
+
+    mock_project.load_settings.assert_called_once_with()
+    mock_project.init.assert_called_once_with(args.type_name, args.language)
+    mock_project.generate.assert_called_once_with()
+
+
+def test_init_method_noninteractive_invalid_type_name():
+    add_dummy_language_plugin()
     type_name = object()
 
-    args = Mock(spec_set=["force", "language"])
+    args = Mock(spec_set=["force", "language", "type_name"])
     args.force = False
-    args.language = "rust1.39"
+    args.language = "dummy"
+    args.type_name = "Test"
 
     mock_project = Mock(spec=Project)
     mock_project.load_settings.side_effect = FileNotFoundError
@@ -76,6 +119,34 @@ def test_init_method_noninteractive_language():
     mock_project.generate.assert_called_once_with()
 
 
+def test_init_method_noninteractive_invalid_language():
+    language = object()
+
+    args = Mock(spec_set=["force", "language", "type_name"])
+    args.force = False
+    args.language = "fortran"
+    args.type_name = "Test::Test::Test"
+
+    mock_project = Mock(spec=Project)
+    mock_project.load_settings.side_effect = FileNotFoundError
+    mock_project.settings_path = ""
+    mock_project.root = Path(".")
+
+    patch_project = patch("rpdk.core.init.Project", return_value=mock_project)
+    patch_tn = patch("rpdk.core.init.input_typename")
+    patch_l = patch("rpdk.core.init.input_language", return_value=language)
+
+    with patch_project, patch_tn as mock_tn, patch_l as mock_l:
+        init(args)
+
+    mock_tn.assert_not_called()
+    mock_l.assert_called_once_with()
+
+    mock_project.load_settings.assert_called_once_with()
+    mock_project.init.assert_called_once_with(args.type_name, language)
+    mock_project.generate.assert_called_once_with()
+
+
 def test_input_with_validation_valid_first_try(capsys):
     sentinel1 = object()
     sentinel2 = object()