implement ops hub extension contract

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a053ff-1d6f-7fe2-ac1c-a6eb40a42a0c

scripts/hub-extension-check.py

@@ -0,0 +1,50 @@
+#!/usr/bin/env python3
+"""Validate the owner package against hub-core's versioned schemas."""
+
+from __future__ import annotations
+
+import argparse
+import json
+from pathlib import Path
+
+from jsonschema import Draft202012Validator, FormatChecker
+
+from ops_hub.extension_contract import load_extension_package, validation_receipt
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--hub-core-repo", type=Path, default=Path("../hub-core"))
+    args = parser.parse_args()
+
+    root = (
+        args.hub_core_repo
+        / "hub_core"
+        / "contracts"
+        / "helixforge_hub_extension"
+        / "v0_1_0"
+    )
+    schemas = root / "schemas"
+    package = load_extension_package()
+    for key, schema_name in (
+        ("descriptor", "hub-descriptor.schema.json"),
+        ("manifest", "hub-manifest.schema.json"),
+    ):
+        schema = json.loads((schemas / schema_name).read_text(encoding="utf-8"))
+        Draft202012Validator.check_schema(schema)
+        Draft202012Validator(schema, format_checker=FormatChecker()).validate(package[key])
+
+    catalog = json.loads((root / "catalogs" / "event-types.json").read_text(encoding="utf-8"))
+    known_events = {entry["type"] for entry in catalog["event_types"]}
+    declared_events = set(package["manifest"]["events_emitted"])
+    declared_events.update(package["manifest"]["events_consumed"])
+    unknown = sorted(declared_events - known_events)
+    if unknown:
+        raise SystemExit("events absent from hub-core catalog: " + ", ".join(unknown))
+
+    print(json.dumps(validation_receipt(), indent=2, sort_keys=True))
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())