* fix(#3189): prevent write_file streaming timeout on long reports
Adds a layered defense against StreamChunkTimeoutError caused by oversized
single-shot write_file tool calls:
- factory: default stream_chunk_timeout to 240s for OpenAI-compatible
clients (overridable via ModelConfig.stream_chunk_timeout in config.yaml)
- sandbox/tools: server-side 80 KB length guard on non-append write_file
calls (configurable via DEERFLOW_WRITE_FILE_MAX_BYTES env var, 0 disables);
rejects oversized payloads with a structured error pointing the model at
str_replace or append=True
- middleware: classify StreamChunkTimeoutError as transient but cap retries
at 1 via per-exception _RETRY_BUDGET_OVERRIDES (same-payload retry on a
chunk-gap timeout buffers the same way upstream; full 3-attempt loop
would stack 6-12 min of dead air)
- middleware: surface an actionable user-facing message for stream-drop
exceptions instead of leaking the raw langchain stack
- prompts: add a routing-style File Editing Workflow hint to both lead_agent
and general_purpose subagent prompts, pointing the model at str_replace
for incremental edits (mirrors Claude Code's Edit / Codex's apply_patch)
- tests: behavioural coverage for size guard, retry budget override,
stream-drop user message, factory default injection
Refs #3189
* fix(#3189): drop stream_chunk_timeout for non-OpenAI providers
Address CR feedback on PR #3195:
- factory: pop `stream_chunk_timeout` from kwargs for any model_use_path other than `langchain_openai:ChatOpenAI` instead of returning early. `ModelConfig.stream_chunk_timeout` is part of the shared schema, so a user-supplied value on a non-OpenAI provider would otherwise be forwarded to its constructor and raise `TypeError: unexpected keyword argument`.
- factory: rewrite docstring to describe the actual `exclude_none=True` behaviour (explicit null is excluded and falls back to the default) instead of the misleading "None falling out via exclude_none=True keeps its value".
- tests: add regression coverage asserting the kwarg is stripped before reaching a non-OpenAI provider's constructor.
Refs: bytedance#3189
* fix(#3189): restrict stream-drop user copy to StreamChunkTimeoutError only
Per CR on #3195: narrow _STREAM_DROP_EXCEPTIONS to StreamChunkTimeoutError. Generic httpx RemoteProtocolError / ReadError fall back to the standard 'temporarily unavailable' copy, since they routinely fire on transient network blips where the 'split the output' guidance is misleading. Retry/backoff classification is unchanged — both remain transient/retriable. Tests updated to reflect new copy, plus a symmetric regression test for ReadError.
---------
Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
* refactor: thread app_config through middleware factories
Continues the incremental config-refactor sequence (#2611 root, #2612 lead
path) one layer deeper into the middleware factories. Two ambient lookups
inside _build_runtime_middlewares are eliminated and the LLMErrorHandling
band-aid removed:
- _build_runtime_middlewares / build_lead_runtime_middlewares /
build_subagent_runtime_middlewares now require app_config: AppConfig.
- get_guardrails_config() inside the factory is replaced with
app_config.guardrails (semantically identical — same default-factory
GuardrailsConfig — verified by direct equality check).
- LLMErrorHandlingMiddleware.__init__ now requires app_config and reads
circuit_breaker fields directly. The class-level
circuit_failure_threshold / circuit_recovery_timeout_sec defaults are
removed along with the try/except (FileNotFoundError, RuntimeError):
pass band-aid — the let-it-crash invariant the rest of the refactor
enforces.
Caller chain (already-resolved app_config sources):
- _build_middlewares in lead_agent/agent.py: reorder so
resolved_app_config = app_config or get_app_config() is computed BEFORE
build_lead_runtime_middlewares is called, then passed as kwarg.
- SubagentExecutor: optional app_config parameter (mirrors the lead-agent
pattern); _create_agent does the same `or get_app_config()` fallback at
agent-build time, so task_tool callers don't need to plumb app_config
through yet (typed-context plumbing for tool runtimes is a separate
refactor).
Tests:
- test_llm_error_handling_middleware: _make_app_config helper using
AppConfig(sandbox=SandboxConfig(use="test")) — same minimal-config
pattern conftest already uses. Three direct LLMErrorHandlingMiddleware()
calls each followed by post-construction circuit_breaker mutation fold
cleanly into _build_middleware(circuit_failure_threshold=...,
circuit_recovery_timeout_sec=...).
Verification:
- tests/test_llm_error_handling_middleware.py — 14 passed
- tests/test_subagent_executor.py — 28 passed
- tests/test_tool_error_handling_middleware.py — 6 passed
- tests/test_task_tool_core_logic.py — 18 passed (verifies task_tool
unchanged behavior)
- Full suite: 2697 passed, 3 skipped. The single intermittent failure in
tests/test_client_e2e.py::test_tool_call_produces_events is pre-existing
LLM flakiness (the test asserts the model decided to call a tool;
reproduces 1/3 on unchanged main as well).
* fix: address middleware app config review comments
* fix: satisfy app config annotation lint
* test: cover explicit app config middleware wiring
---------
Co-authored-by: greatmengqi <chenmengqi.0376@bytedance.com>
Huixin615