[Python] generate metadata files

.chronus/changes/python-metadata-2025-4-15-18-12-43.md

@@ -0,0 +1,7 @@
+---
+changeKind: feature
+packages:
+  - "@typespec/http-client-python"
+---
+
+store apiVersion info in `_metadata.json`

packages/http-client-python/emitter/src/code-model.ts

@@ -323,5 +323,8 @@ export function emitCodeModel(sdkContext: PythonSdkContext) {
     ...simpleTypesMap.values(),
   ];
   codeModel["crossLanguagePackageId"] = ignoreDiagnostics(getCrossLanguagePackageId(sdkContext));
+  if ((sdkContext.emitContext.options as any).flavor === "azure") {
+    codeModel["metadata"] = sdkPackage.metadata;
+  }
   return codeModel;
 }

packages/http-client-python/generator/pygen/codegen/models/code_model.py

@@ -98,6 +98,7 @@ def __init__(
         self.has_subnamespace = False
         self._operations_folder_name: Dict[str, str] = {}
         self._relative_import_path: Dict[str, str] = {}
+        self.metadata: Dict[str, Any] = yaml_data.get("metadata", {})
 
     @staticmethod
     def get_imported_namespace_for_client(imported_namespace: str, async_mode: bool = False) -> str:

packages/http-client-python/generator/pygen/codegen/serializers/__init__.py

@@ -4,6 +4,7 @@
 # license information.
 # --------------------------------------------------------------------------
 import logging
+import json
 from collections import namedtuple
 import re
 from typing import List, Any, Union
@@ -143,6 +144,13 @@ def serialize(self) -> None:
                         self._serialize_and_write_sample(env, namespace=client_namespace)
                     if self.code_model.options["generate_test"]:
                         self._serialize_and_write_test(env, namespace=client_namespace)
+
+                # add _metadata.json
+                if self.code_model.metadata:
+                    self.write_file(
+                        exec_path / Path("_metadata.json"),
+                        json.dumps(self.code_model.metadata, indent=2),
+                    )
             elif client_namespace_type.clients:
                 # add clients folder if there are clients in this namespace
                 self._serialize_client_and_config_files(client_namespace, client_namespace_type.clients, env)