feat: add support for reading apiVersion in discovery artifacts

Author: parthea

googleapiclient/discovery.py

@@ -1170,9 +1170,11 @@ def method(self, **kwargs):
         elif "response" not in methodDesc:
             model = RawModel()
 
+        api_version = methodDesc.get("apiVersion", None)
+
         headers = {}
         headers, params, query, body = model.request(
-            headers, actual_path_params, actual_query_params, body_value
+            headers, actual_path_params, actual_query_params, body_value, api_version
         )
 
         expanded_url = uritemplate.expand(pathUrl, params)

googleapiclient/model.py

@@ -33,6 +33,7 @@
 
 _LIBRARY_VERSION = googleapiclient_version.__version__
 _PY_VERSION = platform.python_version()
+_API_VERSION_HEADER = "x-goog-api-version"
 
 LOGGER = logging.getLogger(__name__)
 
@@ -121,15 +122,18 @@ def _log_request(self, headers, path_params, query, body):
             LOGGER.info("query: %s", query)
             LOGGER.info("--request-end--")
 
-    def request(self, headers, path_params, query_params, body_value):
+    def request(self, headers, path_params, query_params, body_value, api_version=None):
         """Updates outgoing requests with a serialized body.
 
         Args:
           headers: dict, request headers
           path_params: dict, parameters that appear in the request path
           query_params: dict, parameters that appear in the query
           body_value: object, the request body as a Python object, which must be
-                      serializable by json.
+              serializable by json.
+          api_version: str, The precise API version represented by this request,
+              which will result in an API Version header being sent along with the
+              HTTP request.
         Returns:
           A tuple of (headers, path_params, query, body)
 
@@ -154,6 +158,8 @@ def request(self, headers, path_params, query_params, body_value):
             _LIBRARY_VERSION,
             _PY_VERSION,
         )
+        if api_version:
+            headers[_API_VERSION_HEADER] = api_version
 
         if body_value is not None:
             headers["content-type"] = self.content_type

tests/test_json_model.py

@@ -171,6 +171,25 @@ def test_x_goog_api_client(self):
             + " gl-python/"
             + platform.python_version(),
         )
+    
+    def test_x_goog_api_version(self):
+        model = JsonModel(data_wrapper=False)
+
+        # test header composition for cloud clients that wrap discovery
+        headers = {}
+        path_params = {}
+        query_params = {}
+        body = {}
+        api_version = "20240401"
+
+        headers, _, _, body = model.request(
+            headers, path_params, query_params, body, api_version
+        )
+
+        self.assertEqual(
+            headers[googleapiclient.model._API_VERSION_HEADER],
+            api_version,
+        )
 
     def test_bad_response(self):
         model = JsonModel(data_wrapper=False)