Cloud Run strips the Authorization header after using it for IAM
validation, so our JWT middleware can never see the token. When
running on Cloud Run (detected via K_SERVICE env var), skip
app-level JWT verification since Cloud Run IAM already ensures
only authorized service accounts (chat@system.gserviceaccount.com)
can reach the container.
Task history contains multiple status-update messages that may
reference the same A2UI surface. Use only the last non-empty
agent response to avoid duplicate text in Chat output.
The blocking DefaultRequestHandler accumulates intermediate status-update
events into task.history. The A2UI response content from "working" events
lives there, while the final "input-required" status has no message.
Updated extractAllParts to check history. Reverted to blocking mode
since streaming had transport issues.
Verifies Bearer tokens from Google Chat using google-auth-library.
Checks issuer (chat@system.gserviceaccount.com) and audience
(CHAT_PROJECT_NUMBER). Verification is skipped when project number
is not configured, allowing local testing without tokens.
Blocking mode only returns the final task state, missing intermediate
A2UI response content from working status-update events. Streaming
captures all events and aggregates parts into the response.
ClientFactory.createFromUrl expects the full agent card URL
(/.well-known/agent-card.json), not just the base server URL.
Also adds CHAT_BRIDGE_A2A_URL to k8s deployment and test script.
Implements a Google Chat HTTP webhook bridge that connects Google Chat
to the A2A server. Each Chat thread maps to an A2A contextId/taskId
pair. The bridge converts A2UI tool approval surfaces to Google Chat
Cards V2 with Approve/Always Allow/Reject buttons, and handles
CARD_CLICKED events to forward tool confirmations back to the A2A server.
Components:
- chat-bridge/types.ts: Google Chat event/response types
- chat-bridge/session-store.ts: Thread -> A2A session mapping
- chat-bridge/a2a-bridge-client.ts: A2A SDK client wrapper
- chat-bridge/response-renderer.ts: A2UI -> Google Chat Cards V2
- chat-bridge/handler.ts: Event handler (MESSAGE, CARD_CLICKED)
- chat-bridge/routes.ts: Express routes mounted at /chat/webhook
