Checkpointers

Classes:

• CheckpointMetadata –

  Metadata associated with a checkpoint.

• Checkpoint –

  State snapshot at a given point in time.

• BaseCheckpointSaver –

  Base class for creating a graph checkpointer.

Functions:

• create_checkpoint –

  Create a checkpoint for the given channels.

CheckpointMetadata

Bases: TypedDict

Metadata associated with a checkpoint.

Attributes:

• source (Literal['input', 'loop', 'update', 'fork']) –

  The source of the checkpoint.

• step (int) –

  The step number of the checkpoint.

• writes (dict[str, Any]) –

  The writes that were made between the previous checkpoint and this one.

• parents (dict[str, str]) –

  The IDs of the parent checkpoints.

source instance-attribute

source: Literal['input', 'loop', 'update', 'fork']

The source of the checkpoint.

• "input": The checkpoint was created from an input to invoke/stream/batch.
• "loop": The checkpoint was created from inside the pregel loop.
• "update": The checkpoint was created from a manual state update.
• "fork": The checkpoint was created as a copy of another checkpoint.

step instance-attribute

step: int

The step number of the checkpoint.

-1 for the first "input" checkpoint. 0 for the first "loop" checkpoint. ... for the nth checkpoint afterwards.

writes instance-attribute

writes: dict[str, Any]

The writes that were made between the previous checkpoint and this one.

Mapping from node name to writes emitted by that node.

parents instance-attribute

parents: dict[str, str]

The IDs of the parent checkpoints.

Mapping from checkpoint namespace to checkpoint ID.

Checkpoint

Bases: TypedDict

State snapshot at a given point in time.

Attributes:

• v (int) –

  The version of the checkpoint format. Currently 1.

• id (str) –

  The ID of the checkpoint. This is both unique and monotonically

• ts (str) –

  The timestamp of the checkpoint in ISO 8601 format.

• channel_values (dict[str, Any]) –

  The values of the channels at the time of the checkpoint.

• channel_versions (ChannelVersions) –

  The versions of the channels at the time of the checkpoint.

• versions_seen (dict[str, ChannelVersions]) –

  Map from node ID to map from channel name to version seen.

• pending_sends (List[SendProtocol]) –

  List of inputs pushed to nodes but not yet processed.

v instance-attribute

v: int

The version of the checkpoint format. Currently 1.

id instance-attribute

id: str

The ID of the checkpoint. This is both unique and monotonically increasing, so can be used for sorting checkpoints from first to last.

ts instance-attribute

ts: str

The timestamp of the checkpoint in ISO 8601 format.

channel_values instance-attribute

channel_values: dict[str, Any]

The values of the channels at the time of the checkpoint. Mapping from channel name to deserialized channel snapshot value.

channel_versions instance-attribute

channel_versions: ChannelVersions

The versions of the channels at the time of the checkpoint. The keys are channel names and the values are monotonically increasing version strings for each channel.

versions_seen instance-attribute

versions_seen: dict[str, ChannelVersions]

Map from node ID to map from channel name to version seen. This keeps track of the versions of the channels that each node has seen. Used to determine which nodes to execute next.

pending_sends instance-attribute

pending_sends: List[SendProtocol]

List of inputs pushed to nodes but not yet processed. Cleared by the next checkpoint.

BaseCheckpointSaver

Bases: Generic[V]

Base class for creating a graph checkpointer.

Checkpointers allow LangGraph agents to persist their state within and across multiple interactions.

Attributes:

• serde (SerializerProtocol) –

  Serializer for encoding/decoding checkpoints.

Note

When creating a custom checkpoint saver, consider implementing async versions to avoid blocking the main thread.

Methods:

• get –

  Fetch a checkpoint using the given configuration.

• get_tuple –

  Fetch a checkpoint tuple using the given configuration.

• list –

  List checkpoints that match the given criteria.

• put –

  Store a checkpoint with its configuration and metadata.

• put_writes –

  Store intermediate writes linked to a checkpoint.

• delete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

• aget_tuple –

  Asynchronously fetch a checkpoint tuple using the given configuration.

• alist –

  Asynchronously list checkpoints that match the given criteria.

• aput –

  Asynchronously store a checkpoint with its configuration and metadata.

• aput_writes –

  Asynchronously store intermediate writes linked to a checkpoint.

• adelete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

• get_next_version –

  Generate the next version ID for a channel.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Fetch a checkpoint tuple using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The requested checkpoint tuple, or None if not found.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints that match the given criteria.

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria.

• before (Optional[RunnableConfig], default: None ) –

  List checkpoints created before this configuration.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Returns:

• Iterator[CheckpointTuple] –

  Iterator[CheckpointTuple]: Iterator of matching checkpoint tuples.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Store a checkpoint with its configuration and metadata.

Parameters:

• config (RunnableConfig) –

  Configuration for the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to store.

• metadata (CheckpointMetadata) –

  Additional metadata for the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Asynchronously fetch a checkpoint tuple using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The requested checkpoint tuple, or None if not found.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

Asynchronously list checkpoints that match the given criteria.

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  List checkpoints created before this configuration.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Returns:

• AsyncIterator[CheckpointTuple] –

  AsyncIterator[CheckpointTuple]: Async iterator of matching checkpoint tuples.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Asynchronously store a checkpoint with its configuration and metadata.

Parameters:

• config (RunnableConfig) –

  Configuration for the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to store.

• metadata (CheckpointMetadata) –

  Additional metadata for the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Asynchronously store intermediate writes linked to a checkpoint.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

get_next_version

get_next_version(
    current: Optional[V], channel: ChannelProtocol
) -> V

Generate the next version ID for a channel.

Default is to use integer versions, incrementing by 1. If you override, you can use str/int/float versions, as long as they are monotonically increasing.

Parameters:

• current (Optional[V]) –

  The current version identifier (int, float, or str).

• channel (BaseChannel) –

  The channel being versioned.

Returns:

• V ( V ) –

  The next version identifier, which must be increasing.

create_checkpoint

create_checkpoint(
    checkpoint: Checkpoint,
    channels: Optional[Mapping[str, ChannelProtocol]],
    step: int,
    *,
    id: Optional[str] = None
) -> Checkpoint

Create a checkpoint for the given channels.

Classes:

• SerializerProtocol –

  Protocol for serialization and deserialization of objects.

SerializerProtocol

Bases: Protocol

Protocol for serialization and deserialization of objects.

• dumps: Serialize an object to bytes.
• dumps_typed: Serialize an object to a tuple (type, bytes).
• loads: Deserialize an object from bytes.
• loads_typed: Deserialize an object from a tuple (type, bytes).

Valid implementations include the pickle, json and orjson modules.

Classes:

• JsonPlusSerializer –

JsonPlusSerializer

Bases: SerializerProtocol

Classes:

• InMemorySaver –

  An in-memory checkpoint saver.

• PersistentDict –

  Persistent dictionary with an API compatible with shelve and anydbm.

InMemorySaver

Bases: BaseCheckpointSaver[str], AbstractContextManager, AbstractAsyncContextManager

An in-memory checkpoint saver.

This checkpoint saver stores checkpoints in memory using a defaultdict.

Note

Only use InMemorySaver for debugging or testing purposes. For production use cases we recommend installing langgraph-checkpoint-postgres and using PostgresSaver / AsyncPostgresSaver.

If you are using the LangGraph Platform, no checkpointer needs to be specified. The correct managed checkpointer will be used automatically.

Parameters:

• serde (Optional[SerializerProtocol], default: None ) –

  The serializer to use for serializing and deserializing checkpoints. Defaults to None.

Examples:

    import asyncio

    from langgraph.checkpoint.memory import InMemorySaver
    from langgraph.graph import StateGraph

    builder = StateGraph(int)
    builder.add_node("add_one", lambda x: x + 1)
    builder.set_entry_point("add_one")
    builder.set_finish_point("add_one")

    memory = InMemorySaver()
    graph = builder.compile(checkpointer=memory)
    coro = graph.ainvoke(1, {"configurable": {"thread_id": "thread-1"}})
    asyncio.run(coro)  # Output: 2

Methods:

• get_tuple –

  Get a checkpoint tuple from the in-memory storage.

• list –

  List checkpoints from the in-memory storage.

• put –

  Save a checkpoint to the in-memory storage.

• put_writes –

  Save a list of writes to the in-memory storage.

• delete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• aget_tuple –

  Asynchronous version of get_tuple.

• alist –

  Asynchronous version of list.

• aput –

  Asynchronous version of put.

• aput_writes –

  Asynchronous version of put_writes.

• adelete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• get –

  Fetch a checkpoint using the given configuration.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

Attributes:

• config_specs (list[ConfigurableFieldSpec]) –

  Define the configuration options for the checkpoint saver.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the in-memory storage.

This method retrieves a checkpoint tuple from the in-memory storage based on the provided config. If the config contains a "checkpoint_id" key, the checkpoint with the matching thread ID and timestamp is retrieved. Otherwise, the latest checkpoint for the given thread ID is retrieved.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints from the in-memory storage.

This method retrieves a list of checkpoint tuples from the in-memory storage based on the provided criteria.

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  List checkpoints created before this configuration.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Yields:

• CheckpointTuple –

  Iterator[CheckpointTuple]: An iterator of matching checkpoint tuples.

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the in-memory storage.

This method saves a checkpoint to the in-memory storage. The checkpoint is associated with the provided config.

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (dict) –

  New versions as of this write

Returns:

• RunnableConfig ( RunnableConfig ) –

  The updated config containing the saved checkpoint's timestamp.

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Save a list of writes to the in-memory storage.

This method saves a list of writes to the in-memory storage. The writes are associated with the provided config.

Parameters:

• config (RunnableConfig) –

  The config to associate with the writes.

• writes (list[tuple[str, Any]]) –

  The writes to save.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Returns:

• RunnableConfig ( None ) –

  The updated config containing the saved writes' timestamp.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Asynchronous version of get_tuple.

This method is an asynchronous wrapper around get_tuple that runs the synchronous method in a separate thread using asyncio.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

Asynchronous version of list.

This method is an asynchronous wrapper around list that runs the synchronous method in a separate thread using asyncio.

Parameters:

• config (RunnableConfig) –

  The config to use for listing the checkpoints.

Yields:

• AsyncIterator[CheckpointTuple] –

  AsyncIterator[CheckpointTuple]: An asynchronous iterator of checkpoint tuples.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Asynchronous version of put.

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (dict) –

  New versions as of this write

Returns:

• RunnableConfig ( RunnableConfig ) –

  The updated config containing the saved checkpoint's timestamp.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Asynchronous version of put_writes.

This method is an asynchronous wrapper around put_writes that runs the synchronous method in a separate thread using asyncio.

Parameters:

• config (RunnableConfig) –

  The config to associate with the writes.

• writes (List[Tuple[str, Any]]) –

  The writes to save, each as a (channel, value) pair.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Returns:

• None –

  None

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

PersistentDict

Bases: defaultdict

Persistent dictionary with an API compatible with shelve and anydbm.

The dict is kept in memory, so the dictionary operations run as fast as a regular dictionary.

Write to disk is delayed until close or sync (similar to gdbm's fast mode).

Input file format is automatically discovered. Output file format is selectable between pickle, json, and csv. All three serialization formats are backed by fast C implementations.

Adapted from https://code.activestate.com/recipes/576642-persistent-dict-with-multiple-standard-file-format/

Methods:

• sync –

  Write dict to disk

sync

sync() -> None

Write dict to disk

Modules:

• aio –
• utils –

Classes:

• SqliteSaver –

  A checkpoint saver that stores checkpoints in a SQLite database.

SqliteSaver

Bases: BaseCheckpointSaver[str]

A checkpoint saver that stores checkpoints in a SQLite database.

Note

This class is meant for lightweight, synchronous use cases (demos and small projects) and does not scale to multiple threads. For a similar sqlite saver with async support, consider using AsyncSqliteSaver.

Parameters:

• conn (Connection) –

  The SQLite database connection.

• serde (Optional[SerializerProtocol], default: None ) –

  The serializer to use for serializing and deserializing checkpoints. Defaults to JsonPlusSerializerCompat.

Examples:

>>> import sqlite3
>>> from langgraph.checkpoint.sqlite import SqliteSaver
>>> from langgraph.graph import StateGraph
>>>
>>> builder = StateGraph(int)
>>> builder.add_node("add_one", lambda x: x + 1)
>>> builder.set_entry_point("add_one")
>>> builder.set_finish_point("add_one")
>>> # Create a new SqliteSaver instance
>>> # Note: check_same_thread=False is OK as the implementation uses a lock
>>> # to ensure thread safety.
>>> conn = sqlite3.connect("checkpoints.sqlite", check_same_thread=False)
>>> memory = SqliteSaver(conn)
>>> graph = builder.compile(checkpointer=memory)
>>> config = {"configurable": {"thread_id": "1"}}
>>> graph.get_state(config)
>>> result = graph.invoke(3, config)
>>> graph.get_state(config)
StateSnapshot(values=4, next=(), config={'configurable': {'thread_id': '1', 'checkpoint_ns': '', 'checkpoint_id': '0c62ca34-ac19-445d-bbb0-5b4984975b2a'}}, parent_config=None)

Methods:

• from_conn_string –

  Create a new SqliteSaver instance from a connection string.

• setup –

  Set up the checkpoint database.

• cursor –

  Get a cursor for the SQLite database.

• get_tuple –

  Get a checkpoint tuple from the database.

• list –

  List checkpoints from the database.

• put –

  Save a checkpoint to the database.

• put_writes –

  Store intermediate writes linked to a checkpoint.

• delete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• aget_tuple –

  Get a checkpoint tuple from the database asynchronously.

• alist –

  List checkpoints from the database asynchronously.

• aput –

  Save a checkpoint to the database asynchronously.

• get_next_version –

  Generate the next version ID for a channel.

• get –

  Fetch a checkpoint using the given configuration.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

• aput_writes –

  Asynchronously store intermediate writes linked to a checkpoint.

• adelete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

Attributes:

• config_specs (list[ConfigurableFieldSpec]) –

  Define the configuration options for the checkpoint saver.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

from_conn_string classmethod

from_conn_string(conn_string: str) -> Iterator[SqliteSaver]

Create a new SqliteSaver instance from a connection string.

Parameters:

• conn_string (str) –

  The SQLite connection string.

Yields:

• SqliteSaver ( SqliteSaver ) –

  A new SqliteSaver instance.

Examples:

In memory:

    with SqliteSaver.from_conn_string(":memory:") as memory:
        ...

To disk:

    with SqliteSaver.from_conn_string("checkpoints.sqlite") as memory:
        ...

setup

setup() -> None

Set up the checkpoint database.

This method creates the necessary tables in the SQLite database if they don't already exist. It is called automatically when needed and should not be called directly by the user.

cursor

cursor(transaction: bool = True) -> Iterator[Cursor]

Get a cursor for the SQLite database.

This method returns a cursor for the SQLite database. It is used internally by the SqliteSaver and should not be called directly by the user.

Parameters:

• transaction (bool, default: True ) –

  Whether to commit the transaction when the cursor is closed. Defaults to True.

Yields:

• Cursor –

  sqlite3.Cursor: A cursor for the SQLite database.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database.

This method retrieves a checkpoint tuple from the SQLite database based on the provided config. If the config contains a "checkpoint_id" key, the checkpoint with the matching thread ID and checkpoint ID is retrieved. Otherwise, the latest checkpoint for the given thread ID is retrieved.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

Examples:

Basic:
>>> config = {"configurable": {"thread_id": "1"}}
>>> checkpoint_tuple = memory.get_tuple(config)
>>> print(checkpoint_tuple)
CheckpointTuple(...)

With checkpoint ID:

>>> config = {
...    "configurable": {
...        "thread_id": "1",
...        "checkpoint_ns": "",
...        "checkpoint_id": "1ef4f797-8335-6428-8001-8a1503f9b875",
...    }
... }
>>> checkpoint_tuple = memory.get_tuple(config)
>>> print(checkpoint_tuple)
CheckpointTuple(...)

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints from the database.

This method retrieves a list of checkpoint tuples from the SQLite database based on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).

Parameters:

• config (RunnableConfig) –

  The config to use for listing the checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata. Defaults to None.

• before (Optional[RunnableConfig], default: None ) –

  If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.

• limit (Optional[int], default: None ) –

  The maximum number of checkpoints to return. Defaults to None.

Yields:

• CheckpointTuple –

  Iterator[CheckpointTuple]: An iterator of checkpoint tuples.

Examples:

>>> from langgraph.checkpoint.sqlite import SqliteSaver
>>> with SqliteSaver.from_conn_string(":memory:") as memory:
... # Run a graph, then list the checkpoints
>>>     config = {"configurable": {"thread_id": "1"}}
>>>     checkpoints = list(memory.list(config, limit=2))
>>> print(checkpoints)
[CheckpointTuple(...), CheckpointTuple(...)]

>>> config = {"configurable": {"thread_id": "1"}}
>>> before = {"configurable": {"checkpoint_id": "1ef4f797-8335-6428-8001-8a1503f9b875"}}
>>> with SqliteSaver.from_conn_string(":memory:") as memory:
... # Run a graph, then list the checkpoints
>>>     checkpoints = list(memory.list(config, before=before))
>>> print(checkpoints)
[CheckpointTuple(...), ...]

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database.

This method saves a checkpoint to the SQLite database. The checkpoint is associated with the provided config and its parent config (if any).

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Examples:

>>> from langgraph.checkpoint.sqlite import SqliteSaver
>>> with SqliteSaver.from_conn_string(":memory:") as memory:
>>>     config = {"configurable": {"thread_id": "1", "checkpoint_ns": ""}}
>>>     checkpoint = {"ts": "2024-05-04T06:32:42.235444+00:00", "id": "1ef4f797-8335-6428-8001-8a1503f9b875", "channel_values": {"key": "value"}}
>>>     saved_config = memory.put(config, checkpoint, {"source": "input", "step": 1, "writes": {"key": "value"}}, {})
>>> print(saved_config)
{'configurable': {'thread_id': '1', 'checkpoint_ns': '', 'checkpoint_id': '1ef4f797-8335-6428-8001-8a1503f9b875'}}

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint.

This method saves intermediate writes associated with a checkpoint to the SQLite database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (Sequence[Tuple[str, Any]]) –

  List of writes to store, each as (channel, value) pair.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database asynchronously.

Note

This async method is not supported by the SqliteSaver class. Use get_tuple() instead, or consider using AsyncSqliteSaver.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

List checkpoints from the database asynchronously.

Note

This async method is not supported by the SqliteSaver class. Use list() instead, or consider using AsyncSqliteSaver.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database asynchronously.

Note

This async method is not supported by the SqliteSaver class. Use put() instead, or consider using AsyncSqliteSaver.

get_next_version

get_next_version(
    current: Optional[str], channel: ChannelProtocol
) -> str

Generate the next version ID for a channel.

This method creates a new version identifier for a channel based on its current version.

Parameters:

• current (Optional[str]) –

  The current version identifier of the channel.

• channel (BaseChannel) –

  The channel being versioned.

Returns:

• str ( str ) –

  The next version identifier, which is guaranteed to be monotonically increasing.

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Asynchronously store intermediate writes linked to a checkpoint.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

Classes:

• AsyncSqliteSaver –

  An asynchronous checkpoint saver that stores checkpoints in a SQLite database.

AsyncSqliteSaver

Bases: BaseCheckpointSaver[str]

An asynchronous checkpoint saver that stores checkpoints in a SQLite database.

This class provides an asynchronous interface for saving and retrieving checkpoints using a SQLite database. It's designed for use in asynchronous environments and offers better performance for I/O-bound operations compared to synchronous alternatives.

Attributes:

• conn (Connection) –

  The asynchronous SQLite database connection.

• serde (SerializerProtocol) –

  The serializer used for encoding/decoding checkpoints.

Tip

Requires the aiosqlite package. Install it with pip install aiosqlite.

Warning

While this class supports asynchronous checkpointing, it is not recommended for production workloads due to limitations in SQLite's write performance. For production use, consider a more robust database like PostgreSQL.

Tip

Remember to close the database connection after executing your code, otherwise, you may see the graph "hang" after execution (since the program will not exit until the connection is closed).

The easiest way is to use the async with statement as shown in the examples.

async with AsyncSqliteSaver.from_conn_string("checkpoints.sqlite") as saver:
    # Your code here
    graph = builder.compile(checkpointer=saver)
    config = {"configurable": {"thread_id": "thread-1"}}
    async for event in graph.astream_events(..., config, version="v1"):
        print(event)

Examples:

Usage within StateGraph:

>>> import asyncio
>>>
>>> from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver
>>> from langgraph.graph import StateGraph
>>>
>>> async def main():
>>>     builder = StateGraph(int)
>>>     builder.add_node("add_one", lambda x: x + 1)
>>>     builder.set_entry_point("add_one")
>>>     builder.set_finish_point("add_one")
>>>     async with AsyncSqliteSaver.from_conn_string("checkpoints.db") as memory:
>>>         graph = builder.compile(checkpointer=memory)
>>>         coro = graph.ainvoke(1, {"configurable": {"thread_id": "thread-1"}})
>>>         print(await asyncio.gather(coro))
>>>
>>> asyncio.run(main())
Output: [2]

Raw usage:

>>> import asyncio
>>> import aiosqlite
>>> from langgraph.checkpoint.sqlite.aio import AsyncSqliteSaver
>>>
>>> async def main():
>>>     async with aiosqlite.connect("checkpoints.db") as conn:
...         saver = AsyncSqliteSaver(conn)
...         config = {"configurable": {"thread_id": "1", "checkpoint_ns": ""}}
...         checkpoint = {"ts": "2023-05-03T10:00:00Z", "data": {"key": "value"}, "id": "0c62ca34-ac19-445d-bbb0-5b4984975b2a"}
...         saved_config = await saver.aput(config, checkpoint, {}, {})
...         print(saved_config)
>>> asyncio.run(main())
{'configurable': {'thread_id': '1', 'checkpoint_ns': '', 'checkpoint_id': '0c62ca34-ac19-445d-bbb0-5b4984975b2a'}}

Methods:

• from_conn_string –

  Create a new AsyncSqliteSaver instance from a connection string.

• get_tuple –

  Get a checkpoint tuple from the database.

• list –

  List checkpoints from the database asynchronously.

• put –

  Save a checkpoint to the database.

• delete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• setup –

  Set up the checkpoint database asynchronously.

• aget_tuple –

  Get a checkpoint tuple from the database asynchronously.

• alist –

  List checkpoints from the database asynchronously.

• aput –

  Save a checkpoint to the database asynchronously.

• aput_writes –

  Store intermediate writes linked to a checkpoint asynchronously.

• adelete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• get_next_version –

  Generate the next version ID for a channel.

• get –

  Fetch a checkpoint using the given configuration.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

from_conn_string async classmethod

from_conn_string(
    conn_string: str,
) -> AsyncIterator[AsyncSqliteSaver]

Create a new AsyncSqliteSaver instance from a connection string.

Parameters:

• conn_string (str) –

  The SQLite connection string.

Yields:

• AsyncSqliteSaver ( AsyncIterator[AsyncSqliteSaver] ) –

  A new AsyncSqliteSaver instance.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database.

This method retrieves a checkpoint tuple from the SQLite database based on the provided config. If the config contains a "checkpoint_id" key, the checkpoint with the matching thread ID and checkpoint ID is retrieved. Otherwise, the latest checkpoint for the given thread ID is retrieved.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints from the database asynchronously.

This method retrieves a list of checkpoint tuples from the SQLite database based on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Yields:

• CheckpointTuple –

  Iterator[CheckpointTuple]: An iterator of matching checkpoint tuples.

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database.

This method saves a checkpoint to the SQLite database. The checkpoint is associated with the provided config and its parent config (if any).

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

setup async

setup() -> None

Set up the checkpoint database asynchronously.

This method creates the necessary tables in the SQLite database if they don't already exist. It is called automatically when needed and should not be called directly by the user.

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database asynchronously.

This method retrieves a checkpoint tuple from the SQLite database based on the provided config. If the config contains a "checkpoint_id" key, the checkpoint with the matching thread ID and checkpoint ID is retrieved. Otherwise, the latest checkpoint for the given thread ID is retrieved.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

List checkpoints from the database asynchronously.

This method retrieves a list of checkpoint tuples from the SQLite database based on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Yields:

• AsyncIterator[CheckpointTuple] –

  AsyncIterator[CheckpointTuple]: An asynchronous iterator of matching checkpoint tuples.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database asynchronously.

This method saves a checkpoint to the SQLite database. The checkpoint is associated with the provided config and its parent config (if any).

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint asynchronously.

This method saves intermediate writes associated with a checkpoint to the database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (Sequence[Tuple[str, Any]]) –

  List of writes to store, each as (channel, value) pair.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

get_next_version

get_next_version(
    current: Optional[str], channel: ChannelProtocol
) -> str

Generate the next version ID for a channel.

This method creates a new version identifier for a channel based on its current version.

Parameters:

• current (Optional[str]) –

  The current version identifier of the channel.

• channel (BaseChannel) –

  The channel being versioned.

Returns:

• str ( str ) –

  The next version identifier, which is guaranteed to be monotonically increasing.

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

Modules:

• aio –
• base –
• shallow –

Classes:

• BasePostgresSaver –
• ShallowPostgresSaver –

  A checkpoint saver that uses Postgres to store checkpoints.

• PostgresSaver –

BasePostgresSaver

Bases: BaseCheckpointSaver[str]

Methods:

• get –

  Fetch a checkpoint using the given configuration.

• get_tuple –

  Fetch a checkpoint tuple using the given configuration.

• list –

  List checkpoints that match the given criteria.

• put –

  Store a checkpoint with its configuration and metadata.

• put_writes –

  Store intermediate writes linked to a checkpoint.

• delete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

• aget_tuple –

  Asynchronously fetch a checkpoint tuple using the given configuration.

• alist –

  Asynchronously list checkpoints that match the given criteria.

• aput –

  Asynchronously store a checkpoint with its configuration and metadata.

• aput_writes –

  Asynchronously store intermediate writes linked to a checkpoint.

• adelete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

Attributes:

• config_specs (list[ConfigurableFieldSpec]) –

  Define the configuration options for the checkpoint saver.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Fetch a checkpoint tuple using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The requested checkpoint tuple, or None if not found.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints that match the given criteria.

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria.

• before (Optional[RunnableConfig], default: None ) –

  List checkpoints created before this configuration.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Returns:

• Iterator[CheckpointTuple] –

  Iterator[CheckpointTuple]: Iterator of matching checkpoint tuples.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Store a checkpoint with its configuration and metadata.

Parameters:

• config (RunnableConfig) –

  Configuration for the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to store.

• metadata (CheckpointMetadata) –

  Additional metadata for the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Asynchronously fetch a checkpoint tuple using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The requested checkpoint tuple, or None if not found.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

Asynchronously list checkpoints that match the given criteria.

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  List checkpoints created before this configuration.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Returns:

• AsyncIterator[CheckpointTuple] –

  AsyncIterator[CheckpointTuple]: Async iterator of matching checkpoint tuples.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Asynchronously store a checkpoint with its configuration and metadata.

Parameters:

• config (RunnableConfig) –

  Configuration for the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to store.

• metadata (CheckpointMetadata) –

  Additional metadata for the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Asynchronously store intermediate writes linked to a checkpoint.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

ShallowPostgresSaver

Bases: BasePostgresSaver

A checkpoint saver that uses Postgres to store checkpoints.

This checkpointer ONLY stores the most recent checkpoint and does NOT retain any history. It is meant to be a light-weight drop-in replacement for the PostgresSaver that supports most of the LangGraph persistence functionality with the exception of time travel.

Methods:

• get –

  Fetch a checkpoint using the given configuration.

• delete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

• aget_tuple –

  Asynchronously fetch a checkpoint tuple using the given configuration.

• alist –

  Asynchronously list checkpoints that match the given criteria.

• aput –

  Asynchronously store a checkpoint with its configuration and metadata.

• aput_writes –

  Asynchronously store intermediate writes linked to a checkpoint.

• adelete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

• from_conn_string –

  Create a new ShallowPostgresSaver instance from a connection string.

• setup –

  Set up the checkpoint database asynchronously.

• list –

  List checkpoints from the database.

• get_tuple –

  Get a checkpoint tuple from the database.

• put –

  Save a checkpoint to the database.

• put_writes –

  Store intermediate writes linked to a checkpoint.

Attributes:

• config_specs (list[ConfigurableFieldSpec]) –

  Define the configuration options for the checkpoint saver.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Asynchronously fetch a checkpoint tuple using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The requested checkpoint tuple, or None if not found.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

Asynchronously list checkpoints that match the given criteria.

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  List checkpoints created before this configuration.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Returns:

• AsyncIterator[CheckpointTuple] –

  AsyncIterator[CheckpointTuple]: Async iterator of matching checkpoint tuples.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Asynchronously store a checkpoint with its configuration and metadata.

Parameters:

• config (RunnableConfig) –

  Configuration for the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to store.

• metadata (CheckpointMetadata) –

  Additional metadata for the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Asynchronously store intermediate writes linked to a checkpoint.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

from_conn_string classmethod

from_conn_string(
    conn_string: str, *, pipeline: bool = False
) -> Iterator[ShallowPostgresSaver]

Create a new ShallowPostgresSaver instance from a connection string.

Parameters:

• conn_string (str) –

  The Postgres connection info string.

• pipeline (bool, default: False ) –

  whether to use Pipeline

Returns:

• ShallowPostgresSaver ( Iterator[ShallowPostgresSaver] ) –

  A new ShallowPostgresSaver instance.

setup

setup() -> None

Set up the checkpoint database asynchronously.

This method creates the necessary tables in the Postgres database if they don't already exist and runs database migrations. It MUST be called directly by the user the first time checkpointer is used.

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints from the database.

This method retrieves a list of checkpoint tuples from the Postgres database based on the provided config. For ShallowPostgresSaver, this method returns a list with ONLY the most recent checkpoint.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database.

This method retrieves a checkpoint tuple from the Postgres database based on the provided config (matching the thread ID in the config).

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

Examples:

Basic:
>>> config = {"configurable": {"thread_id": "1"}}
>>> checkpoint_tuple = memory.get_tuple(config)
>>> print(checkpoint_tuple)
CheckpointTuple(...)

With timestamp:

>>> config = {
...    "configurable": {
...        "thread_id": "1",
...        "checkpoint_ns": "",
...        "checkpoint_id": "1ef4f797-8335-6428-8001-8a1503f9b875",
...    }
... }
>>> checkpoint_tuple = memory.get_tuple(config)
>>> print(checkpoint_tuple)
CheckpointTuple(...)

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database.

This method saves a checkpoint to the Postgres database. The checkpoint is associated with the provided config. For ShallowPostgresSaver, this method saves ONLY the most recent checkpoint and overwrites a previous checkpoint, if it exists.

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Examples:

>>> from langgraph.checkpoint.postgres import ShallowPostgresSaver
>>> DB_URI = "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable"
>>> with ShallowPostgresSaver.from_conn_string(DB_URI) as memory:
>>>     config = {"configurable": {"thread_id": "1", "checkpoint_ns": ""}}
>>>     checkpoint = {"ts": "2024-05-04T06:32:42.235444+00:00", "id": "1ef4f797-8335-6428-8001-8a1503f9b875", "channel_values": {"key": "value"}}
>>>     saved_config = memory.put(config, checkpoint, {"source": "input", "step": 1, "writes": {"key": "value"}}, {})
>>> print(saved_config)
{'configurable': {'thread_id': '1', 'checkpoint_ns': '', 'checkpoint_id': '1ef4f797-8335-6428-8001-8a1503f9b875'}}

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint.

This method saves intermediate writes associated with a checkpoint to the Postgres database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

PostgresSaver

Bases: BasePostgresSaver

Methods:

• from_conn_string –

  Create a new PostgresSaver instance from a connection string.

• setup –

  Set up the checkpoint database asynchronously.

• list –

  List checkpoints from the database.

• get_tuple –

  Get a checkpoint tuple from the database.

• put –

  Save a checkpoint to the database.

• put_writes –

  Store intermediate writes linked to a checkpoint.

• delete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• get –

  Fetch a checkpoint using the given configuration.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

• aget_tuple –

  Asynchronously fetch a checkpoint tuple using the given configuration.

• alist –

  Asynchronously list checkpoints that match the given criteria.

• aput –

  Asynchronously store a checkpoint with its configuration and metadata.

• aput_writes –

  Asynchronously store intermediate writes linked to a checkpoint.

• adelete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

Attributes:

• config_specs (list[ConfigurableFieldSpec]) –

  Define the configuration options for the checkpoint saver.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

from_conn_string classmethod

from_conn_string(
    conn_string: str, *, pipeline: bool = False
) -> Iterator[PostgresSaver]

Create a new PostgresSaver instance from a connection string.

Parameters:

• conn_string (str) –

  The Postgres connection info string.

• pipeline (bool, default: False ) –

  whether to use Pipeline

Returns:

• PostgresSaver ( Iterator[PostgresSaver] ) –

  A new PostgresSaver instance.

setup

setup() -> None

Set up the checkpoint database asynchronously.

This method creates the necessary tables in the Postgres database if they don't already exist and runs database migrations. It MUST be called directly by the user the first time checkpointer is used.

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints from the database.

This method retrieves a list of checkpoint tuples from the Postgres database based on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).

Parameters:

• config (RunnableConfig) –

  The config to use for listing the checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata. Defaults to None.

• before (Optional[RunnableConfig], default: None ) –

  If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.

• limit (Optional[int], default: None ) –

  The maximum number of checkpoints to return. Defaults to None.

Yields:

• CheckpointTuple –

  Iterator[CheckpointTuple]: An iterator of checkpoint tuples.

Examples:

>>> from langgraph.checkpoint.postgres import PostgresSaver
>>> DB_URI = "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable"
>>> with PostgresSaver.from_conn_string(DB_URI) as memory:
... # Run a graph, then list the checkpoints
>>>     config = {"configurable": {"thread_id": "1"}}
>>>     checkpoints = list(memory.list(config, limit=2))
>>> print(checkpoints)
[CheckpointTuple(...), CheckpointTuple(...)]

>>> config = {"configurable": {"thread_id": "1"}}
>>> before = {"configurable": {"checkpoint_id": "1ef4f797-8335-6428-8001-8a1503f9b875"}}
>>> with PostgresSaver.from_conn_string(DB_URI) as memory:
... # Run a graph, then list the checkpoints
>>>     checkpoints = list(memory.list(config, before=before))
>>> print(checkpoints)
[CheckpointTuple(...), ...]

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database.

This method retrieves a checkpoint tuple from the Postgres database based on the provided config. If the config contains a "checkpoint_id" key, the checkpoint with the matching thread ID and timestamp is retrieved. Otherwise, the latest checkpoint for the given thread ID is retrieved.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

Examples:

Basic:
>>> config = {"configurable": {"thread_id": "1"}}
>>> checkpoint_tuple = memory.get_tuple(config)
>>> print(checkpoint_tuple)
CheckpointTuple(...)

With timestamp:

>>> config = {
...    "configurable": {
...        "thread_id": "1",
...        "checkpoint_ns": "",
...        "checkpoint_id": "1ef4f797-8335-6428-8001-8a1503f9b875",
...    }
... }
>>> checkpoint_tuple = memory.get_tuple(config)
>>> print(checkpoint_tuple)
CheckpointTuple(...)

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database.

This method saves a checkpoint to the Postgres database. The checkpoint is associated with the provided config and its parent config (if any).

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Examples:

>>> from langgraph.checkpoint.postgres import PostgresSaver
>>> DB_URI = "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable"
>>> with PostgresSaver.from_conn_string(DB_URI) as memory:
>>>     config = {"configurable": {"thread_id": "1", "checkpoint_ns": ""}}
>>>     checkpoint = {"ts": "2024-05-04T06:32:42.235444+00:00", "id": "1ef4f797-8335-6428-8001-8a1503f9b875", "channel_values": {"key": "value"}}
>>>     saved_config = memory.put(config, checkpoint, {"source": "input", "step": 1, "writes": {"key": "value"}}, {})
>>> print(saved_config)
{'configurable': {'thread_id': '1', 'checkpoint_ns': '', 'checkpoint_id': '1ef4f797-8335-6428-8001-8a1503f9b875'}}

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint.

This method saves intermediate writes associated with a checkpoint to the Postgres database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Asynchronously fetch a checkpoint tuple using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The requested checkpoint tuple, or None if not found.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

Asynchronously list checkpoints that match the given criteria.

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  List checkpoints created before this configuration.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Returns:

• AsyncIterator[CheckpointTuple] –

  AsyncIterator[CheckpointTuple]: Async iterator of matching checkpoint tuples.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Asynchronously store a checkpoint with its configuration and metadata.

Parameters:

• config (RunnableConfig) –

  Configuration for the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to store.

• metadata (CheckpointMetadata) –

  Additional metadata for the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[Tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Asynchronously store intermediate writes linked to a checkpoint.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (List[Tuple[str, Any]]) –

  List of writes to store.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

Raises:

• NotImplementedError –

  Implement this method in your custom checkpoint saver.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

Classes:

• AsyncShallowPostgresSaver –

  A checkpoint saver that uses Postgres to store checkpoints asynchronously.

• AsyncPostgresSaver –

AsyncShallowPostgresSaver

Bases: BasePostgresSaver

A checkpoint saver that uses Postgres to store checkpoints asynchronously.

This checkpointer ONLY stores the most recent checkpoint and does NOT retain any history. It is meant to be a light-weight drop-in replacement for the AsyncPostgresSaver that supports most of the LangGraph persistence functionality with the exception of time travel.

Methods:

• get –

  Fetch a checkpoint using the given configuration.

• delete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

• adelete_thread –

  Delete all checkpoints and writes associated with a specific thread ID.

• from_conn_string –

  Create a new AsyncShallowPostgresSaver instance from a connection string.

• setup –

  Set up the checkpoint database asynchronously.

• alist –

  List checkpoints from the database asynchronously.

• aget_tuple –

  Get a checkpoint tuple from the database asynchronously.

• aput –

  Save a checkpoint to the database asynchronously.

• aput_writes –

  Store intermediate writes linked to a checkpoint asynchronously.

• list –

  List checkpoints from the database.

• get_tuple –

  Get a checkpoint tuple from the database.

• put –

  Save a checkpoint to the database.

• put_writes –

  Store intermediate writes linked to a checkpoint.

Attributes:

• config_specs (list[ConfigurableFieldSpec]) –

  Define the configuration options for the checkpoint saver.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a specific thread ID.

Parameters:

• thread_id (str) –

  The thread ID whose checkpoints should be deleted.

from_conn_string async classmethod

from_conn_string(
    conn_string: str,
    *,
    pipeline: bool = False,
    serde: Optional[SerializerProtocol] = None
) -> AsyncIterator[AsyncShallowPostgresSaver]

Create a new AsyncShallowPostgresSaver instance from a connection string.

Parameters:

• conn_string (str) –

  The Postgres connection info string.

• pipeline (bool, default: False ) –

  whether to use AsyncPipeline

Returns:

• AsyncShallowPostgresSaver ( AsyncIterator[AsyncShallowPostgresSaver] ) –

  A new AsyncShallowPostgresSaver instance.

setup async

setup() -> None

Set up the checkpoint database asynchronously.

This method creates the necessary tables in the Postgres database if they don't already exist and runs database migrations. It MUST be called directly by the user the first time checkpointer is used.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

List checkpoints from the database asynchronously.

This method retrieves a list of checkpoint tuples from the Postgres database based on the provided config. For ShallowPostgresSaver, this method returns a list with ONLY the most recent checkpoint.

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database asynchronously.

This method retrieves a checkpoint tuple from the Postgres database based on the provided config (matching the thread ID in the config).

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database asynchronously.

This method saves a checkpoint to the Postgres database. The checkpoint is associated with the provided config. For AsyncShallowPostgresSaver, this method saves ONLY the most recent checkpoint and overwrites a previous checkpoint, if it exists.

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint asynchronously.

This method saves intermediate writes associated with a checkpoint to the database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (Sequence[Tuple[str, Any]]) –

  List of writes to store, each as (channel, value) pair.

• task_id (str) –

  Identifier for the task creating the writes.

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints from the database.

This method retrieves a list of checkpoint tuples from the Postgres database based on the provided config. For ShallowPostgresSaver, this method returns a list with ONLY the most recent checkpoint.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database.

This method retrieves a checkpoint tuple from the Postgres database based on the provided config (matching the thread ID in the config).

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database.

This method saves a checkpoint to the Postgres database. The checkpoint is associated with the provided config. For AsyncShallowPostgresSaver, this method saves ONLY the most recent checkpoint and overwrites a previous checkpoint, if it exists.

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint.

This method saves intermediate writes associated with a checkpoint to the database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (Sequence[Tuple[str, Any]]) –

  List of writes to store, each as (channel, value) pair.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

AsyncPostgresSaver

Bases: BasePostgresSaver

Methods:

• from_conn_string –

  Create a new AsyncPostgresSaver instance from a connection string.

• setup –

  Set up the checkpoint database asynchronously.

• alist –

  List checkpoints from the database asynchronously.

• aget_tuple –

  Get a checkpoint tuple from the database asynchronously.

• aput –

  Save a checkpoint to the database asynchronously.

• aput_writes –

  Store intermediate writes linked to a checkpoint asynchronously.

• adelete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• list –

  List checkpoints from the database.

• get_tuple –

  Get a checkpoint tuple from the database.

• put –

  Save a checkpoint to the database.

• put_writes –

  Store intermediate writes linked to a checkpoint.

• delete_thread –

  Delete all checkpoints and writes associated with a thread ID.

• get –

  Fetch a checkpoint using the given configuration.

• aget –

  Asynchronously fetch a checkpoint using the given configuration.

Attributes:

• config_specs (list[ConfigurableFieldSpec]) –

  Define the configuration options for the checkpoint saver.

config_specs property

config_specs: list[ConfigurableFieldSpec]

Define the configuration options for the checkpoint saver.

Returns:

• list[ConfigurableFieldSpec] –

  list[ConfigurableFieldSpec]: List of configuration field specs.

from_conn_string async classmethod

from_conn_string(
    conn_string: str,
    *,
    pipeline: bool = False,
    serde: Optional[SerializerProtocol] = None
) -> AsyncIterator[AsyncPostgresSaver]

Create a new AsyncPostgresSaver instance from a connection string.

Parameters:

• conn_string (str) –

  The Postgres connection info string.

• pipeline (bool, default: False ) –

  whether to use AsyncPipeline

Returns:

• AsyncPostgresSaver ( AsyncIterator[AsyncPostgresSaver] ) –

  A new AsyncPostgresSaver instance.

setup async

setup() -> None

Set up the checkpoint database asynchronously.

This method creates the necessary tables in the Postgres database if they don't already exist and runs database migrations. It MUST be called directly by the user the first time checkpointer is used.

alist async

alist(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> AsyncIterator[CheckpointTuple]

List checkpoints from the database asynchronously.

This method retrieves a list of checkpoint tuples from the Postgres database based on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Yields:

• AsyncIterator[CheckpointTuple] –

  AsyncIterator[CheckpointTuple]: An asynchronous iterator of matching checkpoint tuples.

aget_tuple async

aget_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database asynchronously.

This method retrieves a checkpoint tuple from the Postgres database based on the provided config. If the config contains a "checkpoint_id" key, the checkpoint with the matching thread ID and "checkpoint_id" is retrieved. Otherwise, the latest checkpoint for the given thread ID is retrieved.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

aput async

aput(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database asynchronously.

This method saves a checkpoint to the Postgres database. The checkpoint is associated with the provided config and its parent config (if any).

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

aput_writes async

aput_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint asynchronously.

This method saves intermediate writes associated with a checkpoint to the database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (Sequence[Tuple[str, Any]]) –

  List of writes to store, each as (channel, value) pair.

• task_id (str) –

  Identifier for the task creating the writes.

adelete_thread async

adelete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

list

list(
    config: Optional[RunnableConfig],
    *,
    filter: Optional[dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None
) -> Iterator[CheckpointTuple]

List checkpoints from the database.

This method retrieves a list of checkpoint tuples from the Postgres database based on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).

Parameters:

• config (Optional[RunnableConfig]) –

  Base configuration for filtering checkpoints.

• filter (Optional[Dict[str, Any]], default: None ) –

  Additional filtering criteria for metadata.

• before (Optional[RunnableConfig], default: None ) –

  If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.

• limit (Optional[int], default: None ) –

  Maximum number of checkpoints to return.

Yields:

• CheckpointTuple –

  Iterator[CheckpointTuple]: An iterator of matching checkpoint tuples.

get_tuple

get_tuple(
    config: RunnableConfig,
) -> Optional[CheckpointTuple]

Get a checkpoint tuple from the database.

This method retrieves a checkpoint tuple from the Postgres database based on the provided config. If the config contains a "checkpoint_id" key, the checkpoint with the matching thread ID and "checkpoint_id" is retrieved. Otherwise, the latest checkpoint for the given thread ID is retrieved.

Parameters:

• config (RunnableConfig) –

  The config to use for retrieving the checkpoint.

Returns:

• Optional[CheckpointTuple] –

  Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.

put

put(
    config: RunnableConfig,
    checkpoint: Checkpoint,
    metadata: CheckpointMetadata,
    new_versions: ChannelVersions,
) -> RunnableConfig

Save a checkpoint to the database.

This method saves a checkpoint to the Postgres database. The checkpoint is associated with the provided config and its parent config (if any).

Parameters:

• config (RunnableConfig) –

  The config to associate with the checkpoint.

• checkpoint (Checkpoint) –

  The checkpoint to save.

• metadata (CheckpointMetadata) –

  Additional metadata to save with the checkpoint.

• new_versions (ChannelVersions) –

  New channel versions as of this write.

Returns:

• RunnableConfig ( RunnableConfig ) –

  Updated configuration after storing the checkpoint.

put_writes

put_writes(
    config: RunnableConfig,
    writes: Sequence[tuple[str, Any]],
    task_id: str,
    task_path: str = "",
) -> None

Store intermediate writes linked to a checkpoint.

This method saves intermediate writes associated with a checkpoint to the database.

Parameters:

• config (RunnableConfig) –

  Configuration of the related checkpoint.

• writes (Sequence[Tuple[str, Any]]) –

  List of writes to store, each as (channel, value) pair.

• task_id (str) –

  Identifier for the task creating the writes.

• task_path (str, default: '' ) –

  Path of the task creating the writes.

delete_thread

delete_thread(thread_id: str) -> None

Delete all checkpoints and writes associated with a thread ID.

Parameters:

• thread_id (str) –

  The thread ID to delete.

Returns:

• None –

  None

get

get(config: RunnableConfig) -> Optional[Checkpoint]

Fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

aget async

aget(config: RunnableConfig) -> Optional[Checkpoint]

Asynchronously fetch a checkpoint using the given configuration.

Parameters:

• config (RunnableConfig) –

  Configuration specifying which checkpoint to retrieve.

Returns:

• Optional[Checkpoint] –

  Optional[Checkpoint]: The requested checkpoint, or None if not found.

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