mirror of
https://github.com/langchain-ai/langgraphjs.git
synced 2026-07-22 09:05:28 -04:00
Hunter Lovell
9102d526c8
## Summary This updates Pregel callback manager initialization to pass `tracerInheritableMetadata` defaults derived from `config.configurable`, and narrows `ensureLangGraphConfig` metadata mirroring to the allowlisted LangGraph identifiers used in stream/runtime metadata. ## Changes ### `@langchain/langgraph` (`libs/langgraph-core`) - Updated Pregel callback manager setup to configure core callbacks with `tracerInheritableMetadata` based on configurable primitive values, excluding internal and secret-like keys. - Hoisted tracing default logic into `_getTracingMetadataDefaults` and `_excludeAsMetadata` for parity with the Python implementation shape. - Restricted `ensureLangGraphConfig` configurable-to-metadata propagation to the identifier allowlist: - `thread_id` - `checkpoint_id` - `checkpoint_ns` - `task_id` - `run_id` - `assistant_id` - `graph_id` - Updated config tests to assert the narrowed metadata propagation behavior.
@langchain/langgraph-checkpoint-postgres
Implementation of a LangGraph.js CheckpointSaver that uses a Postgres DB.
Usage
import { PostgresSaver } from "@langchain/langgraph-checkpoint-postgres";
const writeConfig = {
configurable: {
thread_id: "1",
checkpoint_ns: ""
}
};
const readConfig = {
configurable: {
thread_id: "1"
}
};
// you can optionally pass a configuration object as the second parameter
const checkpointer = PostgresSaver.fromConnString("postgresql://...", {
schema: "schema_name" // defaults to "public"
});
// You must call .setup() the first time you use the checkpointer:
await checkpointer.setup();
const checkpoint = {
v: 1,
ts: "2024-07-31T20:14:19.804150+00:00",
id: "1ef4f797-8335-6428-8001-8a1503f9b875",
channel_values: {
my_key: "meow",
node: "node"
},
channel_versions: {
__start__: 2,
my_key: 3,
"start:node": 3,
node: 3
},
versions_seen: {
__input__: {},
__start__: {
__start__: 1
},
node: {
"start:node": 2
}
},
pending_sends: [],
}
// store checkpoint
await checkpointer.put(writeConfig, checkpoint, {}, {});
// load checkpoint
await checkpointer.get(readConfig);
// list checkpoints
for await (const checkpoint of checkpointer.list(readConfig)) {
console.log(checkpoint);
}
Usage with existing connection pool
import { PostgresSaver } from "@langchain/langgraph-checkpoint-postgres";
import pg from "pg";
// You can use any existing postgres connection pool
// we create a new pool here for the sake of the example
const pool = new pg.Pool({
connectionString: "postgresql://..."
});
const checkpointer = new PostgresSaver(pool, undefined, {
schema: "schema_name"
});
await checkpointer.setup();
// ...
Testing
Spin up testing PostgreSQL
docker-compose up -d && docker-compose logs -f
Then use the following connection string to initialize your checkpointer:
const testCheckpointer = PostgresSaver.fromConnString(
"postgresql://user:password@localhost:5434/testdb"
);