Refactors from review: sort extensions in response, small method refactor

Author: mikeas1

src/a2a/server/apps/jsonrpc/jsonrpc_app.py

@@ -392,7 +392,7 @@ def _create_response(
         """
         headers = {}
         if exts := context.activated_extensions:
-            headers[HTTP_EXTENSION_HEADER] = ', '.join(exts)
+            headers[HTTP_EXTENSION_HEADER] = ', '.join(sorted(exts))
         if isinstance(handler_result, AsyncGenerator):
             # Result is a stream of SendStreamingMessageResponse objects
             async def event_generator(

src/a2a/server/request_handlers/grpc_handler.py

@@ -52,19 +52,13 @@ def _get_metadata_value(
     context: grpc.aio.ServicerContext, key: str
 ) -> list[str]:
     md = context.invocation_metadata
-    vs = []
+    raw_values: list[str | bytes] = []
     if isinstance(md, Metadata):
-        vs = [
-            e if isinstance(e, str) else e.decode('utf-8')
-            for e in md.get_all(key)
-        ]
+        raw_values = md.get_all(key)
     elif isinstance(md, Sequence):
-        vs = [
-            e if isinstance(e, str) else e.decode('utf-8')
-            for (k, e) in md
-            if k == key.lower()
-        ]
-    return vs
+        lower_key = key.lower()
+        raw_values = [e for (k, e) in md if k == lower_key]
+    return [e if isinstance(e, str) else e.decode('utf-8') for e in raw_values]
 
 
 class DefaultCallContextBuilder(CallContextBuilder):
@@ -414,6 +408,6 @@ def _set_extension_metadata(
             context.set_trailing_metadata(
                 [
                     (HTTP_EXTENSION_HEADER, e)
-                    for e in server_context.activated_extensions
+                    for e in sorted(server_context.activated_extensions)
                 ]
             )