feat(gateway): implement LangGraph Platform API in Gateway, replace langgraph-cli (#1403)

* feat(gateway): implement LangGraph Platform API in Gateway, replace langgraph-cli

Implement all core LangGraph Platform API endpoints in the Gateway,
allowing it to fully replace the langgraph-cli dev server for local
development. This eliminates a heavyweight dependency and simplifies
the development stack.

Changes:
- Add runs lifecycle endpoints (create, stream, wait, cancel, join)
- Add threads CRUD and search endpoints
- Add assistants compatibility endpoints (search, get, graph, schemas)
- Add StreamBridge (in-memory pub/sub for SSE) and async provider
- Add RunManager with atomic create_or_reject (eliminates TOCTOU race)
- Add worker with interrupt/rollback cancel actions and runtime context injection
- Route /api/langgraph/* to Gateway in nginx config
- Skip langgraph-cli startup by default (SKIP_LANGGRAPH_SERVER=0 to restore)
- Add unit tests for RunManager, SSE format, and StreamBridge

* fix: drain bridge queue on client disconnect to prevent backpressure

When on_disconnect=continue, keep consuming events from the bridge
without yielding, so the worker is not blocked by a full queue.
Only on_disconnect=cancel breaks out immediately.

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix: remove pytest import

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix: Fix default stream_mode to ["values", "messages-tuple"]

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix: Remove unused if_exists field from ThreadCreateRequest

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix: address review comments on gateway LangGraph API

- Mount runs.py router in app.py (missing include_router)
- Normalize interrupt_before/after "*" to node list before run_agent()
- Use entry.id for SSE event ID instead of counter
- Drain bridge queue on disconnect when on_disconnect=continue
- Reuse serialization helper in wait_run() for consistent wire format
- Reject unsupported multitask_strategy with 400
- Remove SKIP_LANGGRAPH_SERVER fallback, always use Gateway

* feat: extract app.state access into deps.py

Encapsulate read/write operations for singleton objects (RunManager,
StreamBridge, checkpointer) held in app.state into a shared utility,
reducing repeated access patterns across router modules.

* feat: extract deerflow.runtime.serialization module with tests

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* refactor: replace duplicated serialization with deerflow.runtime.serialization

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* feat: extract app/gateway/services.py with run lifecycle logic

Create a service layer that centralizes SSE formatting, input/config
normalization, and run lifecycle management. Router modules will delegate
to these functions instead of using private cross-imported helpers.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* refactor: wire routers to use services layer, remove cross-module private imports

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* style: apply ruff formatting to refactored files

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* feat(runtime): support LangGraph dev server and add compat route

- Enable official LangGraph dev server for local development workflow
- Decouple runtime components from agents package for better separation
- Provide gateway-backed fallback route when dev server is skipped
- Simplify lifecycle management using context manager in gateway

* feat(runtime): add Store providers with auto-backend selection

- Add async_provider.py and provider.py under deerflow/runtime/store/
- Support memory, sqlite, postgres backends matching checkpointer config
- Integrate into FastAPI lifespan via AsyncExitStack in deps.py
- Replace hardcoded InMemoryStore with config-driven factory

* refactor(gateway): migrate thread management from checkpointer to Store and resolve multiple endpoint failures

- Add Store-backed CRUD helpers (_store_get, _store_put, _store_upsert)
- Replace checkpoint-scanning search with two-phase strategy:
  phase 1 reads Store (O(threads)), phase 2 backfills from checkpointer
  for legacy/LangGraph Server threads with lazy migration
- Extend Store record schema with values field for title persistence
- Sync thread title from checkpoint to Store after run completion
- Fix /threads/{id}/runs/{run_id}/stream 405 by accepting both
  GET and POST methods; POST handles interrupt/rollback actions
- Fix /threads/{id}/state 500 by separating read_config and
  write_config, adding checkpoint_ns to configurable, and
  shallow-copying checkpoint/metadata before mutation
- Sync title to Store on state update for immediate search reflection
- Move _upsert_thread_in_store into services.py, remove duplicate logic
- Add _sync_thread_title_after_run: await run task, read final
  checkpoint title, write back to Store record
- Spawn title sync as background task from start_run when Store exists

* refactor(runtime): deduplicate store and checkpointer provider logic

Extract _ensure_sqlite_parent_dir() helper into checkpointer/provider.py
and use it in all three places that previously inlined the same mkdir logic.
Consolidate duplicate error constants in store/async_provider.py by importing
from store/provider.py instead of redefining them.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* refactor(runtime): move SQLite helpers to runtime/store, checkpointer imports from store

_resolve_sqlite_conn_str and _ensure_sqlite_parent_dir now live in
runtime/store/provider.py. agents/checkpointer/provider and
agents/checkpointer/async_provider import from there, reversing the
previous dependency direction (store → checkpointer becomes
checkpointer → store).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* refactor(runtime): extract SQLite helpers into runtime/store/_sqlite_utils.py

Move resolve_sqlite_conn_str and ensure_sqlite_parent_dir out of
checkpointer/provider.py into a dedicated _sqlite_utils module.
Functions are now public (no underscore prefix), making cross-module
imports semantically correct. All four provider files import from
the single shared location.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix(gateway): use adelete_thread to fully remove thread checkpoints on delete

AsyncSqliteSaver has no adelete method — the previous hasattr check
always evaluated to False, silently leaving all checkpoint rows in the
database. Switch to adelete_thread(thread_id) which deletes every
checkpoint and pending-write row for the thread across all namespaces
(including sub-graph checkpoints).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix(gateway): remove dead bridge_cm/ckpt_cm code and fix StrEnum lint

app.py had unreachable code after the async-with lifespan refactor:
bridge_cm and ckpt_cm were referenced but never defined (F821), and
the channel service startup/shutdown was outside the langgraph_runtime
block so it never ran. Move channel service lifecycle inside the
async-with block where it belongs.

Replace str+Enum inheritance in RunStatus and DisconnectMode with
StrEnum as suggested by UP042.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* style: format with ruff

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: JeffJiang <for-eleven@hotmail.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
This commit is contained in:
rayhpeng
2026-03-30 16:02:23 +08:00
committed by GitHub
parent 7db95926b0
commit 34e835bc33
35 changed files with 3492 additions and 66 deletions
+102
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"""Tests for app.gateway.services — run lifecycle service layer."""
from __future__ import annotations
import json
def test_format_sse_basic():
from app.gateway.services import format_sse
frame = format_sse("metadata", {"run_id": "abc"})
assert frame.startswith("event: metadata\n")
assert "data: " in frame
parsed = json.loads(frame.split("data: ")[1].split("\n")[0])
assert parsed["run_id"] == "abc"
def test_format_sse_with_event_id():
from app.gateway.services import format_sse
frame = format_sse("metadata", {"run_id": "abc"}, event_id="123-0")
assert "id: 123-0" in frame
def test_format_sse_end_event_null():
from app.gateway.services import format_sse
frame = format_sse("end", None)
assert "data: null" in frame
def test_format_sse_no_event_id():
from app.gateway.services import format_sse
frame = format_sse("values", {"x": 1})
assert "id:" not in frame
def test_normalize_stream_modes_none():
from app.gateway.services import normalize_stream_modes
assert normalize_stream_modes(None) == ["values"]
def test_normalize_stream_modes_string():
from app.gateway.services import normalize_stream_modes
assert normalize_stream_modes("messages-tuple") == ["messages-tuple"]
def test_normalize_stream_modes_list():
from app.gateway.services import normalize_stream_modes
assert normalize_stream_modes(["values", "messages-tuple"]) == ["values", "messages-tuple"]
def test_normalize_stream_modes_empty_list():
from app.gateway.services import normalize_stream_modes
assert normalize_stream_modes([]) == ["values"]
def test_normalize_input_none():
from app.gateway.services import normalize_input
assert normalize_input(None) == {}
def test_normalize_input_with_messages():
from app.gateway.services import normalize_input
result = normalize_input({"messages": [{"role": "user", "content": "hi"}]})
assert len(result["messages"]) == 1
assert result["messages"][0].content == "hi"
def test_normalize_input_passthrough():
from app.gateway.services import normalize_input
result = normalize_input({"custom_key": "value"})
assert result == {"custom_key": "value"}
def test_build_run_config_basic():
from app.gateway.services import build_run_config
config = build_run_config("thread-1", None, None)
assert config["configurable"]["thread_id"] == "thread-1"
assert config["recursion_limit"] == 100
def test_build_run_config_with_overrides():
from app.gateway.services import build_run_config
config = build_run_config(
"thread-1",
{"configurable": {"model_name": "gpt-4"}, "tags": ["test"]},
{"user": "alice"},
)
assert config["configurable"]["model_name"] == "gpt-4"
assert config["tags"] == ["test"]
assert config["metadata"]["user"] == "alice"
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"""Tests for RunManager."""
import re
import pytest
from deerflow.runtime import RunManager, RunStatus
ISO_RE = re.compile(r"^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}")
@pytest.fixture
def manager() -> RunManager:
return RunManager()
@pytest.mark.anyio
async def test_create_and_get(manager: RunManager):
"""Created run should be retrievable with new fields."""
record = await manager.create(
"thread-1",
"lead_agent",
metadata={"key": "val"},
kwargs={"input": {}},
multitask_strategy="reject",
)
assert record.status == RunStatus.pending
assert record.thread_id == "thread-1"
assert record.assistant_id == "lead_agent"
assert record.metadata == {"key": "val"}
assert record.kwargs == {"input": {}}
assert record.multitask_strategy == "reject"
assert ISO_RE.match(record.created_at)
assert ISO_RE.match(record.updated_at)
fetched = manager.get(record.run_id)
assert fetched is record
@pytest.mark.anyio
async def test_status_transitions(manager: RunManager):
"""Status should transition pending -> running -> success."""
record = await manager.create("thread-1")
assert record.status == RunStatus.pending
await manager.set_status(record.run_id, RunStatus.running)
assert record.status == RunStatus.running
assert ISO_RE.match(record.updated_at)
await manager.set_status(record.run_id, RunStatus.success)
assert record.status == RunStatus.success
@pytest.mark.anyio
async def test_cancel(manager: RunManager):
"""Cancel should set abort_event and transition to interrupted."""
record = await manager.create("thread-1")
await manager.set_status(record.run_id, RunStatus.running)
cancelled = await manager.cancel(record.run_id)
assert cancelled is True
assert record.abort_event.is_set()
assert record.status == RunStatus.interrupted
@pytest.mark.anyio
async def test_cancel_not_inflight(manager: RunManager):
"""Cancelling a completed run should return False."""
record = await manager.create("thread-1")
await manager.set_status(record.run_id, RunStatus.success)
cancelled = await manager.cancel(record.run_id)
assert cancelled is False
@pytest.mark.anyio
async def test_list_by_thread(manager: RunManager):
"""Same thread should return multiple runs, newest first."""
r1 = await manager.create("thread-1")
r2 = await manager.create("thread-1")
await manager.create("thread-2")
runs = await manager.list_by_thread("thread-1")
assert len(runs) == 2
assert runs[0].run_id == r2.run_id
assert runs[1].run_id == r1.run_id
@pytest.mark.anyio
async def test_has_inflight(manager: RunManager):
"""has_inflight should be True when a run is pending or running."""
record = await manager.create("thread-1")
assert await manager.has_inflight("thread-1") is True
await manager.set_status(record.run_id, RunStatus.success)
assert await manager.has_inflight("thread-1") is False
@pytest.mark.anyio
async def test_cleanup(manager: RunManager):
"""After cleanup, the run should be gone."""
record = await manager.create("thread-1")
run_id = record.run_id
await manager.cleanup(run_id, delay=0)
assert manager.get(run_id) is None
@pytest.mark.anyio
async def test_set_status_with_error(manager: RunManager):
"""Error message should be stored on the record."""
record = await manager.create("thread-1")
await manager.set_status(record.run_id, RunStatus.error, error="Something went wrong")
assert record.status == RunStatus.error
assert record.error == "Something went wrong"
@pytest.mark.anyio
async def test_get_nonexistent(manager: RunManager):
"""Getting a nonexistent run should return None."""
assert manager.get("does-not-exist") is None
@pytest.mark.anyio
async def test_create_defaults(manager: RunManager):
"""Create with no optional args should use defaults."""
record = await manager.create("thread-1")
assert record.metadata == {}
assert record.kwargs == {}
assert record.multitask_strategy == "reject"
assert record.assistant_id is None
+159
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"""Tests for deerflow.runtime.serialization."""
from __future__ import annotations
class _FakePydanticV2:
"""Object with model_dump (Pydantic v2)."""
def model_dump(self):
return {"key": "v2"}
class _FakePydanticV1:
"""Object with dict (Pydantic v1)."""
def dict(self):
return {"key": "v1"}
class _Unprintable:
"""Object whose str() raises."""
def __str__(self):
raise RuntimeError("no str")
def __repr__(self):
return "<Unprintable>"
def test_serialize_none():
from deerflow.runtime.serialization import serialize_lc_object
assert serialize_lc_object(None) is None
def test_serialize_primitives():
from deerflow.runtime.serialization import serialize_lc_object
assert serialize_lc_object("hello") == "hello"
assert serialize_lc_object(42) == 42
assert serialize_lc_object(3.14) == 3.14
assert serialize_lc_object(True) is True
def test_serialize_dict():
from deerflow.runtime.serialization import serialize_lc_object
obj = {"a": _FakePydanticV2(), "b": [1, "two"]}
result = serialize_lc_object(obj)
assert result == {"a": {"key": "v2"}, "b": [1, "two"]}
def test_serialize_list():
from deerflow.runtime.serialization import serialize_lc_object
result = serialize_lc_object([_FakePydanticV1(), 1])
assert result == [{"key": "v1"}, 1]
def test_serialize_tuple():
from deerflow.runtime.serialization import serialize_lc_object
result = serialize_lc_object((_FakePydanticV2(),))
assert result == [{"key": "v2"}]
def test_serialize_pydantic_v2():
from deerflow.runtime.serialization import serialize_lc_object
assert serialize_lc_object(_FakePydanticV2()) == {"key": "v2"}
def test_serialize_pydantic_v1():
from deerflow.runtime.serialization import serialize_lc_object
assert serialize_lc_object(_FakePydanticV1()) == {"key": "v1"}
def test_serialize_fallback_str():
from deerflow.runtime.serialization import serialize_lc_object
result = serialize_lc_object(object())
assert isinstance(result, str)
def test_serialize_fallback_repr():
from deerflow.runtime.serialization import serialize_lc_object
assert serialize_lc_object(_Unprintable()) == "<Unprintable>"
def test_serialize_channel_values_strips_pregel_keys():
from deerflow.runtime.serialization import serialize_channel_values
raw = {
"messages": ["hello"],
"__pregel_tasks": "internal",
"__pregel_resuming": True,
"__interrupt__": "stop",
"title": "Test",
}
result = serialize_channel_values(raw)
assert "messages" in result
assert "title" in result
assert "__pregel_tasks" not in result
assert "__pregel_resuming" not in result
assert "__interrupt__" not in result
def test_serialize_channel_values_serializes_objects():
from deerflow.runtime.serialization import serialize_channel_values
result = serialize_channel_values({"obj": _FakePydanticV2()})
assert result == {"obj": {"key": "v2"}}
def test_serialize_messages_tuple():
from deerflow.runtime.serialization import serialize_messages_tuple
chunk = _FakePydanticV2()
metadata = {"langgraph_node": "agent"}
result = serialize_messages_tuple((chunk, metadata))
assert result == [{"key": "v2"}, {"langgraph_node": "agent"}]
def test_serialize_messages_tuple_non_dict_metadata():
from deerflow.runtime.serialization import serialize_messages_tuple
result = serialize_messages_tuple((_FakePydanticV2(), "not-a-dict"))
assert result == [{"key": "v2"}, {}]
def test_serialize_messages_tuple_fallback():
from deerflow.runtime.serialization import serialize_messages_tuple
result = serialize_messages_tuple("not-a-tuple")
assert result == "not-a-tuple"
def test_serialize_dispatcher_messages_mode():
from deerflow.runtime.serialization import serialize
chunk = _FakePydanticV2()
result = serialize((chunk, {"node": "x"}), mode="messages")
assert result == [{"key": "v2"}, {"node": "x"}]
def test_serialize_dispatcher_values_mode():
from deerflow.runtime.serialization import serialize
result = serialize({"msg": "hi", "__pregel_tasks": "x"}, mode="values")
assert result == {"msg": "hi"}
def test_serialize_dispatcher_default_mode():
from deerflow.runtime.serialization import serialize
result = serialize(_FakePydanticV1())
assert result == {"key": "v1"}
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"""Tests for SSE frame formatting utilities."""
import json
def _format_sse(event: str, data, *, event_id: str | None = None) -> str:
from app.gateway.services import format_sse
return format_sse(event, data, event_id=event_id)
def test_sse_end_event_data_null():
"""End event should have data: null."""
frame = _format_sse("end", None)
assert "data: null" in frame
def test_sse_metadata_event():
"""Metadata event should include run_id and attempt."""
frame = _format_sse("metadata", {"run_id": "abc", "attempt": 1}, event_id="123-0")
assert "event: metadata" in frame
assert "id: 123-0" in frame
def test_sse_error_format():
"""Error event should use message/name format."""
frame = _format_sse("error", {"message": "boom", "name": "ValueError"})
parsed = json.loads(frame.split("data: ")[1].split("\n")[0])
assert parsed["message"] == "boom"
assert parsed["name"] == "ValueError"
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"""Tests for the in-memory StreamBridge implementation."""
import asyncio
import re
import pytest
from deerflow.runtime import END_SENTINEL, HEARTBEAT_SENTINEL, MemoryStreamBridge, make_stream_bridge
# ---------------------------------------------------------------------------
# Unit tests for MemoryStreamBridge
# ---------------------------------------------------------------------------
@pytest.fixture
def bridge() -> MemoryStreamBridge:
return MemoryStreamBridge(queue_maxsize=256)
@pytest.mark.anyio
async def test_publish_subscribe(bridge: MemoryStreamBridge):
"""Three events followed by end should be received in order."""
run_id = "run-1"
await bridge.publish(run_id, "metadata", {"run_id": run_id})
await bridge.publish(run_id, "values", {"messages": []})
await bridge.publish(run_id, "updates", {"step": 1})
await bridge.publish_end(run_id)
received = []
async for entry in bridge.subscribe(run_id, heartbeat_interval=1.0):
received.append(entry)
if entry is END_SENTINEL:
break
assert len(received) == 4
assert received[0].event == "metadata"
assert received[1].event == "values"
assert received[2].event == "updates"
assert received[3] is END_SENTINEL
@pytest.mark.anyio
async def test_heartbeat(bridge: MemoryStreamBridge):
"""When no events arrive within the heartbeat interval, yield a heartbeat."""
run_id = "run-heartbeat"
bridge._get_or_create_queue(run_id) # ensure queue exists
received = []
async def consumer():
async for entry in bridge.subscribe(run_id, heartbeat_interval=0.1):
received.append(entry)
if entry is HEARTBEAT_SENTINEL:
break
await asyncio.wait_for(consumer(), timeout=2.0)
assert len(received) == 1
assert received[0] is HEARTBEAT_SENTINEL
@pytest.mark.anyio
async def test_cleanup(bridge: MemoryStreamBridge):
"""After cleanup, the run's queue is removed."""
run_id = "run-cleanup"
await bridge.publish(run_id, "test", {})
assert run_id in bridge._queues
await bridge.cleanup(run_id)
assert run_id not in bridge._queues
assert run_id not in bridge._counters
@pytest.mark.anyio
async def test_backpressure():
"""With maxsize=1, publish should not block forever."""
bridge = MemoryStreamBridge(queue_maxsize=1)
run_id = "run-bp"
await bridge.publish(run_id, "first", {})
# Second publish should either succeed after queue drains or warn+drop
# It should not hang indefinitely
async def publish_second():
await bridge.publish(run_id, "second", {})
# Give it a generous timeout — the publish timeout is 30s but we don't
# want to wait that long in tests. Instead, drain the queue first.
async def drain():
await asyncio.sleep(0.05)
bridge._queues[run_id].get_nowait()
await asyncio.gather(publish_second(), drain())
assert bridge._queues[run_id].qsize() == 1
@pytest.mark.anyio
async def test_multiple_runs(bridge: MemoryStreamBridge):
"""Two different run_ids should not interfere with each other."""
await bridge.publish("run-a", "event-a", {"a": 1})
await bridge.publish("run-b", "event-b", {"b": 2})
await bridge.publish_end("run-a")
await bridge.publish_end("run-b")
events_a = []
async for entry in bridge.subscribe("run-a", heartbeat_interval=1.0):
events_a.append(entry)
if entry is END_SENTINEL:
break
events_b = []
async for entry in bridge.subscribe("run-b", heartbeat_interval=1.0):
events_b.append(entry)
if entry is END_SENTINEL:
break
assert len(events_a) == 2
assert events_a[0].event == "event-a"
assert events_a[0].data == {"a": 1}
assert len(events_b) == 2
assert events_b[0].event == "event-b"
assert events_b[0].data == {"b": 2}
@pytest.mark.anyio
async def test_event_id_format(bridge: MemoryStreamBridge):
"""Event IDs should use timestamp-sequence format."""
run_id = "run-id-format"
await bridge.publish(run_id, "test", {"key": "value"})
await bridge.publish_end(run_id)
received = []
async for entry in bridge.subscribe(run_id, heartbeat_interval=1.0):
received.append(entry)
if entry is END_SENTINEL:
break
event = received[0]
assert re.match(r"^\d+-\d+$", event.id), f"Expected timestamp-seq format, got {event.id}"
# ---------------------------------------------------------------------------
# Factory tests
# ---------------------------------------------------------------------------
@pytest.mark.anyio
async def test_make_stream_bridge_defaults():
"""make_stream_bridge() with no config yields a MemoryStreamBridge."""
async with make_stream_bridge() as bridge:
assert isinstance(bridge, MemoryStreamBridge)