Started implementing manifest validating

pre_commit/clientlib/validate_manifest.py

@@ -0,0 +1,98 @@
+
+from __future__ import print_function
+
+import argparse
+import jsonschema
+import jsonschema.exceptions
+import os.path
+import yaml
+
+import pre_commit.constants as C
+
+
+class InvalidManifestError(ValueError): pass
+
+
+MANIFEST_JSON_SCHEMA = {
+    'type': 'object',
+    'properties': {
+        'hooks': {
+            'type': 'array',
+            'minItems': 1,
+            'items': {
+                'type': 'object',
+                'properties': {
+                    'id': {'type': 'string'},
+                    'name': {'type': 'string'},
+                    'description': {'type': 'string'},
+                    'entry': {'type': 'string'},
+                    'language': {'type': 'string'},
+                    'expected_return_value': {'type': 'number'},
+                },
+                'required': ['id', 'name', 'entry'],
+            },
+        },
+    },
+    'required': ['hooks'],
+}
+
+
+def check_is_valid_manifest(file_contents):
+    file_objects = yaml.load(file_contents)
+
+    jsonschema.validate(file_objects, MANIFEST_JSON_SCHEMA)
+
+    for hook_config in file_objects['hooks']:
+        language = hook_config.get('language')
+
+        if language is not None and not any(
+            language.startswith(lang) for lang in C.SUPPORTED_LANGUAGES
+        ):
+            raise InvalidManifestError(
+                'Expected language {0} for {1} to start with one of {2!r}'.format(
+                    hook_config['id'],
+                    hook_config['language'],
+                    C.SUPPORTED_LANGUAGES,
+                )
+            )
+
+
+
+def run(argv):
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        '--filename',
+        required=False, default=None,
+        help='Manifest filename.  Defaults to {0} at root of git repo'.format(
+            C.MANIFEST_FILE,
+        )
+    )
+    args = parser.parse_args(argv)
+
+    if args.filename is None:
+        # TODO: filename = git.get_root() + C.MANIFEST_FILE
+        raise NotImplementedError
+    else:
+        filename = args.filename
+
+    if not os.path.exists(filename):
+        print('File {0} does not exist'.format(filename))
+        return 1
+
+    file_contents = open(filename, 'r').read()
+
+    try:
+        yaml.load(file_contents)
+    except Exception as e:
+        print('File {0} is not a valid yaml file'.format(filename))
+        print(str(e))
+        return 1
+
+    try:
+        check_is_valid_manifest(file_contents)
+    except (jsonschema.exceptions.ValidationError, InvalidManifestError) as e:
+        print('File {0} is not a valid manifest file'.format(filename))
+        print(str(e))
+        return 1
+
+    return 0