Add blueprint metadata validation tool

tools/validate_metadata.py

@@ -0,0 +1,93 @@
+#!/usr/bin/env python3
+
+# Copyright 2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+'''Validate a YAML file against the standard blueprint metadata schema[1]
+
+[1] https://github.com/GoogleCloudPlatform/cloud-foundation-toolkit/blob/master/cli/bpmetadata/schema/bpmetadataschema.json
+'''
+
+import enum
+import json
+import sys
+from dataclasses import dataclass
+from pathlib import Path
+
+import click
+import jsonschema
+import yaml
+
+SCHEMA_PATH = Path(__file__).parent / 'bpmetadataschema.json'
+
+
+class State(enum.Enum):
+  INVALID: int = 0
+  OK: int = 1
+
+
+@dataclass
+class ValidationResult:
+  state: State
+  errors: dict[str, str]
+
+
+def _validate(path: Path, validator) -> ValidationResult:
+  with open(path) as f:
+    metadata = yaml.safe_load(f)
+
+  errors = {
+      error.json_path: error.message
+      for error in validator.iter_errors(metadata)
+  }
+
+  state = State.OK if not errors else State.INVALID
+  return ValidationResult(state=state, errors=errors)
+
+
+@click.command()
+@click.argument('dirs', type=click.Path(exists=True, file_okay=False), nargs=-1)
+@click.option('-v', '--verbose', is_flag=True, default=False,
+              help='Print additional validation details.')
+def main(dirs: str, verbose: bool) -> int:
+  instances = set()
+  for dir_name in dirs:
+    instances |= set(Path(dir_name).glob("**/metadata.yaml"))
+
+  with open(SCHEMA_PATH) as f:
+    schema = json.load(f)
+  validator = jsonschema.validators.Draft202012Validator(schema)
+
+  results = {}
+  for instance in instances:
+    result = _validate(instance, validator)
+    if result.state == State.OK:
+      print(f'[✓] {instance}')
+    else:
+      print(f'[✗] {instance}')
+      results[instance] = result.errors
+
+  if verbose:
+    for file_path, errors in results.items():
+      print(f"\n====== {file_path!s} ======")
+      for path, message in errors.items():
+        print(f"{path}: {message}")
+
+  if errors:
+    return 1
+
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main())