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Nick HollonandGitHub
68fa011fc9
## Summary
- Adds `stream_events(version="v3")` and `astream_events(version="v3")`
to `RemoteGraph`, matching the local `CompiledStateGraph` surface and
unblocking polymorphic v3 streaming over `Graph | RemoteGraph`.
- Implementation is a thin adapter
(`libs/langgraph/langgraph/pregel/_remote_run_stream.py`) that wraps the
v3 SDK's `AsyncThreadStream` / `SyncThreadStream` and duck-types
`GraphRunStream` / `AsyncGraphRunStream`. No coupling to local v3 mux
internals.
- `v1` / `v2` paths unchanged. `astream_events(version='v1'|'v2')` still
raises `NotImplementedError` (separate gap).
### Scope decisions baked into this PR
- Unsupported v3 kwargs hard-reject at dispatch with
`NotImplementedError`: `control`, `transformers`, `interrupt_before`,
`interrupt_after`, and any unknown `**kwargs`. Server / SDK don't plumb
these through v3 yet; easy to lift later.
- Sync `interleave()` raises `NotImplementedError` pointing callers at
`astream_events`. Real sync interleave would need drainer threads;
deferred since most sync RemoteGraph callers just iterate raw events.
- Async `interleave()` is best-effort ordering (client receive order),
documented as a divergence from local v3's monotonic stamp ordering.
- Adapter `interrupted` / `interrupts` properties are **non-blocking**
snapshots of the SDK's current state. This differs from local
`(Async)GraphRunStream.interrupted`, which pump-drives the run to
terminal before returning. Callers needing a wait-for-interrupt pattern
should drain a projection (e.g., `interleave('values')`) until the SDK's
paused sentinel fires. Documented in the adapter docstrings.
### Audit of impact
Existing RemoteGraph callers in this org all use the v2 `.stream()` /
`.astream()` path (deepagents production wrapper, langgraph-api test
graphs, langgraph-supervisor TS type guard). **Zero callers** use
`stream_events` / `astream_events` on RemoteGraph today, so the new v3
methods are net-new surface — no risk of breaking existing consumers.
### Out of scope (follow-ups)
- Bumping `libs/langgraph/pyproject.toml`'s `langgraph-sdk` constraint
from `<0.4.0` to `<0.5.0`. Deferred until 0.4.0 publishes to PyPI; dev
resolution unaffected via the editable workspace dep.
- Real `astream_events(version='v1'|'v2')` implementation.
- Server-side plumbing for `control` / `interrupt_before` /
`interrupt_after` on v3 runs.
- Sync `interleave()` via drainer threads.
## Test plan
- [x] \`make test\` in \`libs/langgraph/\`: 1874 passed, 4 skipped (43
new in \`test_remote_graph_v3.py\`)
- [x] \`make lint\` in \`libs/langgraph/\`: ruff + mypy clean
- [x] \`pytest -m integration
tests/integration/test_remote_graph_v3.py\` in \`libs/sdk-py/\` against
the docker stack: 4/4 passed in 1.35s
- [x] Manual smoke: \`RemoteGraph('tools_agent',
url='http://localhost:2024').astream_events(..., version='v3')\`
end-to-end against the v3 integration api
- [x] Existing RemoteGraph v2 tests untouched (31 passed, 3 skipped with
docker up)
- [x] Will need rebase after \`langgraph-sdk 0.4.0\` lands on PyPI and
the version constraint is bumped in a separate PR