fix: ensure correct agent URL path parsing and registration in Starlette app

Signed-off-by: Shingo OKAWA <[email protected]>

Author: ognis1205

examples/apicatalog/__main__.py

@@ -5,21 +5,17 @@
 
 import click
 import uvicorn
+from dotenv import load_dotenv
 
-from agent_executors import (
-    HelloWorldAgentExecutor, # type: ignore[import-untyped]
-    EchoAgentExecutor, # type: ignore[import-untyped]
+from agent_executors import (  # type: ignore[import-untyped]
+    EchoAgentExecutor,
+    HelloWorldAgentExecutor,
 )
 
-from a2a.server.apps import A2AStarletteRouteBuilder, A2AStarletteBuilder
+from a2a.server.apps import A2AStarletteBuilder, A2AStarletteRouteBuilder
 from a2a.server.request_handlers import DefaultRequestHandler
 from a2a.server.tasks import InMemoryTaskStore
-from a2a.types import (
-    AgentCapabilities,
-    AgentCard,
-    AgentSkill,
-)
-from dotenv import load_dotenv
+from a2a.types import AgentCapabilities, AgentCard, AgentSkill
 
 
 load_dotenv()

examples/apicatalog/test_client.py

@@ -1,12 +1,12 @@
 import asyncio
+import json
 import logging
 import os
 import sys
 import traceback
 
 import click
 import httpx
-
 from dotenv import load_dotenv
 
 
@@ -28,7 +28,7 @@ async def fetch_api_catalog(base_url: str):
 def main(host: str, port: int):
     base = f'http://{host}:{port}'
     catalog = asyncio.run(fetch_api_catalog(base))
-    print(catalog)
+    print(json.dumps(catalog))
 
 
 if __name__ == "__main__":

src/a2a/server/apps/starlette_app.py

@@ -824,8 +824,11 @@ def _join_url(base: str, *paths: str) -> str:
     """
     parsed = urlparse(base)
     clean_paths = [p.strip('/') for p in paths]
-    joined_path = posixpath.join(parsed.path.rstrip('/'), *clean_paths)
-    return urlunparse(parsed._replace(path='/' + joined_path))
+    base_path = parsed.path if parsed.path != '/' else ''
+    base_path = base_path.strip('/')
+    joined_path = posixpath.join(base_path, *clean_paths)
+    final_path = '/' + joined_path if joined_path else '/'
+    return urlunparse(parsed._replace(path=final_path))
 
 
 def _get_path_from_url(url: str) -> str:
@@ -904,13 +907,12 @@ def mount(
         routes = route_builder.build()
         self._mounts.append(Mount(path, routes=routes))
         anchor = _join_url(
-            route_builder.agent_card.url, path, route_builder.rpc_path
+            route_builder.agent_card.url, route_builder.rpc_path
         )
         describedby = [
             AgentLinkTarget(
                 href=_join_url(
                     route_builder.agent_card.url,
-                    path,
                     route_builder.agent_card_path,
                 )
             )
@@ -923,7 +925,6 @@ def mount(
                 AgentLinkTarget(
                     href=_join_url(
                         route_builder.extended_agent_card.url,
-                        path,
                         route_builder.extended_agent_card_path,
                     )
                 )