Fixes/upgrades

protocol/mizan-codegen/scripts/run_pydantic_to_rust.py

@@ -0,0 +1,91 @@
+#!/usr/bin/env python3
+"""Report a Pydantic module's declarations as JSON on stdout.
+
+Takes one argv JSON object of `module` and `derives`; returns `enums` as
+name plus variant identifiers, and `structs` as rendered Rust source.
+"""
+
+import importlib
+import inspect
+import json
+import sys
+from enum import Enum
+from pathlib import Path
+
+from pydantic import BaseModel
+
+from pydantic_to_rust import (
+    emit_rust_struct,
+    to_rust_variant_ident,
+    walk_pydantic_model,
+)
+
+
+def _declared_in(module, obj) -> bool:
+    return getattr(obj, "__module__", None) == module.__name__
+
+
+def discover_models(module) -> list[type[BaseModel]]:
+    """BaseModel subclasses declared here. An imported one is another
+    module's to emit."""
+    return [
+        obj
+        for _, obj in inspect.getmembers(module, inspect.isclass)
+        if issubclass(obj, BaseModel)
+        and obj is not BaseModel
+        and _declared_in(module, obj)
+    ]
+
+
+def discover_enums(module) -> list[type[Enum]]:
+    """Enum subclasses declared here. Only variant identifiers are reported;
+    the caller renders the enum body."""
+    return [
+        obj
+        for _, obj in inspect.getmembers(module, inspect.isclass)
+        if issubclass(obj, Enum) and obj is not Enum and _declared_in(module, obj)
+    ]
+
+
+def main() -> int:
+    if len(sys.argv) < 2:
+        sys.stderr.write("run_pydantic_to_rust.py: missing JSON payload argument\n")
+        return 2
+
+    payload = json.loads(sys.argv[1])
+    module_name: str = payload["module"]
+    derives = tuple(payload["derives"])
+
+    sys.path.insert(0, str(Path.cwd()))
+
+    module = importlib.import_module(module_name)
+    enums = discover_enums(module)
+    models = discover_models(module)
+    if not enums and not models:
+        sys.stderr.write(
+            f"run_pydantic_to_rust.py: no Enum or BaseModel subclasses "
+            f"declared in {module_name!r}\n"
+        )
+        return 3
+
+    json.dump(
+        {
+            "enums": [
+                {
+                    "name": enum_class.__name__,
+                    "variants": [to_rust_variant_ident(m.name) for m in enum_class],
+                }
+                for enum_class in enums
+            ],
+            "structs": [
+                emit_rust_struct(walk_pydantic_model(model), derives=derives)
+                for model in models
+            ],
+        },
+        sys.stdout,
+    )
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())