Code review finding (P2): when chat_stream successfully emits the first
chunk (broadcasted to UI) but then breaks during subsequent chunks, the
fallback path called gateway.chat() and broadcasted the FULL content
via _replay_stream — causing the UI to see partial streamed content
followed by duplicated full content.
Fix: if `total` already contains partial content from first_chunk,
return it directly without calling gateway.chat(). Partial content is
better than duplicated content. The non-streaming fallback only runs
when no chunks were broadcasted (total is empty).
Add test_stream_breaks_after_first_chunk_returns_partial covering this
edge case: first chunk yields "部分内容", second __anext__ raises
RuntimeError. Asserts result is the partial content, gateway.chat() is
never called, and broadcast_event is called exactly once (for the
first chunk only).
Commit 36b0296 changed expert speech generation from gateway.chat()
(non-streaming) to gateway.chat_stream() (streaming) for progressive
UI output. However, DashScope/DeepSeek via LiteLLM occasionally accept
the streaming request but never emit the first SSE chunk — the async
generator hangs indefinitely with no error and no timeout, freezing
the entire board.
Root cause: `async for chunk in gateway.chat_stream(...)` blocks
forever when the provider silently stalls. The moderator path
(gateway.chat) still works because it's synchronous — that's why
the moderator opening always succeeds but experts hang.
Fix: pull the first chunk via `__anext__()` wrapped in
`asyncio.wait_for(timeout=30s)`. If no chunk arrives within 30s,
close the stream and fall back to non-streaming gateway.chat() +
_replay_stream() (which splits the response into small chunks for
progressive UI rendering). This preserves the "逐个输出" UX while
guaranteeing the board never hangs on a stalled streaming provider.
Add 4 unit tests covering:
- Normal streaming works (existing path)
- First-chunk timeout → fallback to chat()
- Empty stream → fallback to chat()
- chat_stream raising → fallback to chat()
E2E verification: 5-expert board with DashScope completes in ~277s
(status=completed), all experts produce content, no hang.
Same branch as the earlier _handle_llm_gateway fix (commit d0fe661).
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Replace emoji across codebase: YAML avatars -> first char, frontend banners -> Ant Design Vue components, CLI status -> OK/FAIL/WARN labels, terminal -> [WARN]/[OK]/[PENDING], Bitable DB default -> table, App.vue font cleanup, test fixtures -> first char letters. shell.avatar type upgraded to string | Component.
Chiguyong
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