ޠjwVSSKJr SSKrSSKrSSKJrJrJrJrJ r SSK J r J r J r JrJrJr SSKJr SSKJr SSKJr SSKJrJr SS KJr SS KJr SS KJrJ r J!r!J"r"J#r# \"S \$\%\&5r'\(\&\&\ 4r)\RT"\+5r,"S S\SS9r-\.\&\&\$-\%-4r/"SS\5r0S)Sjr1"SS\5r2"SS\5r3"SS\ \'5r4S*Sjr5"SS\65r7S+Sjr8S,Sjr9S,Sjr:\S \"S!\ S"\!S#0r;1S$krSS'.S.S(jjr?g)/) annotationsN) AsyncIterator CollectionIteratorMappingSequence)AnyGenericLiteral NamedTuple TypedDictTypeVar)RunnableConfig) NotRequired)uuid6)SerializerProtocolmaybe_add_typed_methods)EncryptedSerializer)JsonPlusSerializer)ERROR INTERRUPTRESUME SCHEDULEDChannelProtocolVcT\rSrSr%SrS\S'S\S'S\S'S \S 'S \S 'S rg)CheckpointMetadata&z&Metadata associated with a checkpoint.z*Literal['input', 'loop', 'update', 'fork']sourceintstepzdict[str, str]parentsstrrun_idzdict[str, tuple[int, int]]counters_since_delta_snapshotN__name__ __module__ __qualname____firstlineno____doc____annotations____static_attributes__r&\/var/www/html/gaurav/venv/lib/python3.13/site-packages/langgraph/checkpoint/base/__init__.pyrr&s>0 66 I  K9#==r/rF)totalcl\rSrSr%SrS\S'S\S'S\S'S\S 'S \S 'S \S 'S\S'Srg) Checkpoint\z(State snapshot at a given point in time.r vr#idtszdict[str, Any]channel_valuesChannelVersionschannel_versionszdict[str, ChannelVersions] versions_seenzlist[str] | Noneupdated_channelsr&Nr'r&r/r0r3r3\sS2 F> G' G=""&% .- '&r/r3cF[USUSUSUSR5USR5USR5VVs0sHupXR5_M snnURS/5R5URSS5S 9$s snnf) Nr5r7r6r8r:r; pending_sendsr<r5r7r6r8r:r;r>r<)r3copyitemsget) checkpointkr5s r0copy_checkpointrE~s  S/ d  d !"2388:#$67<<>/9//J/P/P/RS/Rtqq&&({/RS nn_b9>>@#(:DA   Ts BcT\rSrSr%SrS\S'S\S'S\S'S rS \S 'S rS \S 'Srg )CheckpointTuplez8A tuple containing a checkpoint and its associated data.rconfigr3rCrmetadataNRunnableConfig | None parent_configzlist[PendingWrite] | Nonepending_writesr&) r(r)r*r+r,r-rLrMr.r&r/r0rGrGs-B   +/M(/04N-4r/rGc.\rSrSr%SrS\S'S\S'Srg) DeltaChannelHistoryuPer-channel result entry from `BaseCheckpointSaver.get_delta_channel_history`. !!! warning "Beta" Part of the `DeltaChannel` support surface; in beta. Field names and semantics may change. Storage-level view of what one channel contributed across the ancestor chain of a target checkpoint: * `writes` — on-path deltas oldest→newest as `PendingWrite` tuples. Always present; possibly empty. Already filtered to one channel. Writes stored at the target checkpoint itself are pending for the next super-step and are excluded. * `seed` — the stored value at the nearest ancestor whose `channel_values[ch]` is populated. Omitted if the walk reached the root without finding any stored value (consumer treats absence as "start empty"). Typically a `_DeltaSnapshot` for delta channels with finite snapshot frequency, or a plain value for threads migrated from a pre-delta channel type. zlist[PendingWrite]writeszNotRequired[Any]seedr&Nr'r&r/r0rOrOs,  r/rOcJ\rSrSr%Sr\"5rS\S'SS.S"Sjjr\ S#Sj5r S$S jr S%S jr SSSS .S&S jjr S'S jrS(S)SjjrS*SjrS+SjrS,SjrSS.S-SjjrS$SjrS%SjrSSSS .S.SjjrS'SjrS(S)SjjrS*SjrS+SjrS,SjrSS.S-SjjrS/SjrS/SjrS0S jrS1S!jr Sr!g)2BaseCheckpointSavera$Base class for creating a graph checkpointer. Checkpointers allow LangGraph agents to persist their state within and across multiple interactions. When a checkpointer is configured, you should pass a `thread_id` in the config when invoking the graph: ```python config = {"configurable": {"thread_id": "my-thread"}} graph.invoke(inputs, config) ``` The `thread_id` is the primary key used to store and retrieve checkpoints. Without it, the checkpointer cannot save state, resume from interrupts, or enable time-travel debugging. How you choose ``thread_id`` depends on your use case: - **Single-shot workflows**: Use a unique ID (e.g., uuid4) for each run when executions are independent. - **Conversational memory**: Reuse the same `thread_id` across invocations to accumulate state (e.g., chat history) within a conversation. 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. rserdeN)rVcJ[U=(d UR5Ulg)N)rrV)selfrVs r0__init__BaseCheckpointSaver.__init__s -U-@djjA r/c/$)zrDefine the configuration options for the checkpoint saver. Returns: list: List of configuration field specs. r&)rXs r0 config_specs BaseCheckpointSaver.config_specss  r/cLURU5=n(a UR$g)zFetch a checkpoint using the given configuration. Args: config: Configuration specifying which checkpoint to retrieve. Returns: The requested checkpoint, or `None` if not found. N) get_tuplerCrXrIvalues r0rBBaseCheckpointSaver.gets)NN6* *5 *## # +r/c[e)a!Fetch a checkpoint tuple using the given configuration. Args: config: Configuration specifying which checkpoint to retrieve. Returns: The requested checkpoint tuple, or `None` if not found. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. NotImplementedErrorrXrIs r0r_BaseCheckpointSaver.get_tuples "!r/)filterbeforelimitc[e)aList checkpoints that match the given criteria. Args: config: Base configuration for filtering checkpoints. filter: Additional filtering criteria. before: List checkpoints created before this configuration. limit: Maximum number of checkpoints to return. Returns: Iterator of matching checkpoint tuples. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. rdrXrIrhrirjs r0listBaseCheckpointSaver.list ,"!r/c[e)aStore a checkpoint with its configuration and metadata. Args: config: Configuration for the checkpoint. checkpoint: The checkpoint to store. metadata: Additional metadata for the checkpoint. new_versions: New channel versions as of this write. Returns: RunnableConfig: Updated configuration after storing the checkpoint. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. rdrXrIrCrJ new_versionss r0putBaseCheckpointSaver.puts *"!r/c[e)a[Store intermediate writes linked to a checkpoint. Args: config: Configuration of the related checkpoint. writes: List of writes to store. task_id: Identifier for the task creating the writes. task_path: Path of the task creating the writes. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. rdrXrIrQtask_id task_paths r0 put_writesBaseCheckpointSaver.put_writes,s $"!r/c[ezDelete all checkpoints and writes associated with a specific thread ID. Args: thread_id: The thread ID whose checkpoints should be deleted. rdrX thread_ids r0 delete_thread!BaseCheckpointSaver.delete_thread@s "!r/c[e)uDelete all checkpoints and writes associated with the given run IDs. Args: run_ids: The run IDs whose checkpoints should be deleted. !!! warning "DeltaChannel" Deleting a run that produced ancestor `checkpoint_writes` — or the only `_DeltaSnapshot` blob — for a still-live thread will break reconstruction of any `DeltaChannel` whose history depended on those rows. See the `DeltaChannel` note on `prune` for safe-recovery strategies. rdrXrun_idss r0delete_for_runs#BaseCheckpointSaver.delete_for_runsKs ""!r/c[e)uCopy all checkpoints and writes from one thread to another. Args: source_thread_id: The thread ID to copy from. target_thread_id: The thread ID to copy to. !!! warning "DeltaChannel" Implementations must copy the **complete** parent chain (all ancestor checkpoints and their `checkpoint_writes`) — copying only the head checkpoint will leave the target thread with `DeltaChannel` state that cannot be reconstructed (no path back to a `_DeltaSnapshot` ancestor). Equivalently, the copy must include enough ancestors that every `DeltaChannel`-backed key has either a `_DeltaSnapshot` in `channel_values` somewhere in the chain, or a complete write history back to the chain root. rdrXsource_thread_idtarget_thread_ids r0 copy_threadBaseCheckpointSaver.copy_thread^ror/ keep_latest)strategyc[e)ulPrune checkpoints for the given threads. Args: thread_ids: The thread IDs to prune. strategy: The pruning strategy. `"keep_latest"` retains only the most recent checkpoint per namespace. `"delete"` removes all checkpoints. !!! warning "DeltaChannel" Custom implementations must be `DeltaChannel`-aware. `DeltaChannel` stores only a sentinel in `channel_values` for non-snapshot steps; reconstruction walks the parent chain via `get_delta_channel_history`, accumulating rows from `checkpoint_writes` until it reaches an ancestor whose `channel_values` contains a `_DeltaSnapshot` blob (written every `snapshot_frequency` updates). A naive `"keep_latest"` that drops intermediate checkpoints and their writes can sever that chain: the surviving "latest" checkpoint is rarely a snapshot point itself, so its delta channels would silently reconstruct as empty (no error raised — `get_delta_channel_history` simply returns no `seed`). Safe options when the graph uses `DeltaChannel`: * Walk back from each kept checkpoint and preserve every ancestor (plus its `checkpoint_writes`) up to the nearest one whose `channel_values` already contains a `_DeltaSnapshot` for every `DeltaChannel`-backed key. * Force a fresh snapshot on the kept checkpoint before deleting ancestors — rewrite `channel_values[k] = _DeltaSnapshot(value)` for each delta channel `k` (resolving `value` via the existing ancestor walk first), then prune. * Skip pruning threads whose graph uses `DeltaChannel` until one of the above is implemented. rdrX thread_idsrs r0pruneBaseCheckpointSaver.prunevs R"!r/ch# URU5IShvN =n(a UR$gN7f)zAsynchronously fetch a checkpoint using the given configuration. Args: config: Configuration specifying which checkpoint to retrieve. Returns: The requested checkpoint, or `None` if not found. N) aget_tuplerCr`s r0agetBaseCheckpointSaver.agets2//&11 15 1## # 21s 202c# [e7f)a0Asynchronously fetch a checkpoint tuple using the given configuration. Args: config: Configuration specifying which checkpoint to retrieve. Returns: The requested checkpoint tuple, or `None` if not found. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. rdrfs r0rBaseCheckpointSaver.aget_tuples "! c# [e7f)aAsynchronously list checkpoints that match the given criteria. Args: config: Base configuration for filtering checkpoints. filter: Additional filtering criteria for metadata. before: List checkpoints created before this configuration. limit: Maximum number of checkpoints to return. Returns: Async iterator of matching checkpoint tuples. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. rdrls r0alistBaseCheckpointSaver.alists ,"!rc# [e7f)aAsynchronously store a checkpoint with its configuration and metadata. Args: config: Configuration for the checkpoint. checkpoint: The checkpoint to store. metadata: Additional metadata for the checkpoint. new_versions: New channel versions as of this write. Returns: RunnableConfig: Updated configuration after storing the checkpoint. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. rdrqs r0aputBaseCheckpointSaver.aputs *"!rc# [e7f)ajAsynchronously store intermediate writes linked to a checkpoint. Args: config: Configuration of the related checkpoint. writes: List of writes to store. task_id: Identifier for the task creating the writes. task_path: Path of the task creating the writes. Raises: NotImplementedError: Implement this method in your custom checkpoint saver. rdrvs r0 aput_writesBaseCheckpointSaver.aput_writes $"!rc# [e7fr|rdr}s r0adelete_thread"BaseCheckpointSaver.adelete_threads "!rc# [e7f)uAsynchronously delete all checkpoints and writes for the given run IDs. Args: run_ids: The run IDs whose checkpoints should be deleted. !!! warning "DeltaChannel" See `delete_for_runs` — deleting rows a still-live thread's `DeltaChannel` reconstruction depends on (writes between the head and its nearest `_DeltaSnapshot` ancestor) will silently corrupt that channel's state. rdrs r0adelete_for_runs$BaseCheckpointSaver.adelete_for_runs s "!rc# [e7f)uAsynchronously copy all checkpoints and writes from one thread to another. Args: source_thread_id: The thread ID to copy from. target_thread_id: The thread ID to copy to. !!! warning "DeltaChannel" See `copy_thread` — the copy must carry the complete parent chain (or at least back to a `_DeltaSnapshot` ancestor for every `DeltaChannel`) so the target thread can reconstruct delta state. rdrs r0 acopy_thread BaseCheckpointSaver.acopy_threadrrc# [e7f)a(Asynchronously prune checkpoints for the given threads. Args: thread_ids: The thread IDs to prune. strategy: The pruning strategy. `"keep_latest"` retains only the most recent checkpoint per namespace. `"delete"` removes all checkpoints. !!! warning "DeltaChannel" See `prune` for the full `DeltaChannel` caveat. In short: `"keep_latest"` must not drop ancestor checkpoints / writes that sit between the kept checkpoint and the nearest `_DeltaSnapshot` ancestor, or delta channels will silently reconstruct as empty. rdrs r0apruneBaseCheckpointSaver.aprune0s ("!rcU(d0$UVs0sHo3/_M nn0n[U5nURU5nU(a UROSnUbU(aURU5n U cOU R(a;[ U R5H"n U Sn X;dMXKR U 5 M$ [ U5H<n XRS;dMU RSU X['URU 5 M> U RnUb U(aM0n UH+n S[ [ XK550n X;aX[U S'XU 'M- U $s snf)uWalk the parent chain returning per-channel writes + seed. !!! warning "Beta" This method is part of the `DeltaChannel` support surface and is in beta. The signature, return shape (`DeltaChannelHistory`), and interaction with `_DeltaSnapshot` blobs may change. Override at your own risk; the default implementation will continue to work against the public `BaseCheckpointSaver` contract. For each requested channel, walks ancestors of the checkpoint identified by `config` (following `parent_config`) and accumulates `pending_writes` for that channel. The walk terminates per-channel at the nearest ancestor whose `channel_values[ch]` is populated; that value is returned as `seed`. If the walk reaches the root without finding a stored value, `seed` is omitted from that channel's entry — the consumer treats the absence as "start empty." Walks the **parent chain** (not `list(before=...)`): for forked threads, only on-path ancestors contribute. The default implementation walks `get_tuple` + `parent_config` once for all channels — each ancestor visited once, not once per channel. Savers with direct storage access (`InMemorySaver`, `PostgresSaver`) override for performance; the return contract is fixed here. Args: config: Configuration identifying the target checkpoint. channels: Channel names to walk for. Empty → empty mapping. Returns: Per-channel `DeltaChannelHistory` for every name in `channels`. Nr8rQrR) setr_rLrMreversedappendrmrCdiscardrXrIchannelsccollected_by_ch seed_by_ch remaining target_tuple cursor_configtupwritechresultentrys r0get_delta_channel_history-BaseCheckpointSaver.get_delta_channel_historyFsXLIIQ9RAR%9R%' !(m ~~f- *6L & &D 'I../C{!!%c&8&89EqB'+2259:9o(899%(^^4D%Eb%IJN%%b)& --M'II24B*2D/BU9V4W)XE *f 2J   7:Ss Ec# U(d0$UVs0sHo3/_M nn0n[U5nURU5IShvN nU(a UROSnUbU(aURU5IShvN n U cOU R(a;[ U R5H"n U Sn X;dMXKR U 5 M$ [ U5H<n XRS;dMU RSU X['URU 5 M> U RnUb U(aM0n UH+n S[ [ XK550n X;aX[U S'XU 'M- U $s snfGN*N7f)zAsync version of `get_delta_channel_history`. !!! warning "Beta" This method is part of the `DeltaChannel` support surface and is in beta. See `get_delta_channel_history` for caveats. Nrr8rQrR) rrrLrMrrrmrCrrs r0aget_delta_channel_history.BaseCheckpointSaver.aget_delta_channel_historysjIIQ9RAR%9R%' !(m !__V44 *6L & &D 'I 66C{!!%c&8&89EqB'+2259:9o(899%(^^4D%Eb%IJN%%b)& --M'II24B*2D/BU9V4W)XE *f 2J   7:S5 7s=E- E##E-E(7E-6E+79E-45E--?E-.;E-+E-cJ[U[5(a[eUcgUS-$)aGenerate 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. Args: current: The current version identifier (`int`, `float`, or `str`). channel: Deprecated argument, kept for backwards compatibility. Returns: V: The next version identifier, which must be increasing. r) isinstancer#re)rXcurrentchannels r0get_next_version$BaseCheckpointSaver.get_next_versions) gs # #% % _Q; r/c[URU5nX RLaU$[R"U5n[U5UlU$)z8Return a shallow clone with a derived msgpack allowlist.)_with_msgpack_allowlistrVr@r)rXextra_allowlistrVclones r0with_allowlist"BaseCheckpointSaver.with_allowlistsA( OD JJ K $-e4  r/)rVzSerializerProtocol | NonereturnNone)rrm)rIrrzCheckpoint | None)rIrrzCheckpointTuple | None) rIrKrhdict[str, Any] | NonerirKrj int | NonerzIterator[CheckpointTuple]) rIrrCr3rJrrrr9rr)) rIrrQzSequence[tuple[str, Any]]rwr#rxr#rr)r~r#rr)r Sequence[str]rr)rr#rr#rr)rrrr#rr) rIrKrhrrirKrjrrzAsyncIterator[CheckpointTuple])rIrrrrz!Mapping[str, DeltaChannelHistory])rzV | Nonerrrr)rCollection[tuple[str, ...]]rzBaseCheckpointSaver[V])"r(r)r*r+r,rrVr-rYpropertyr\rBr_rmrsryrrrrrrrrrrrrrrrrrr.r&r/r0rTrTs@!3 4E 4 ,0B)B  B $ "$)-(, "%"& " & "  " #"0"""% " & "  "8 ""*" "  "  "( " "  """ "&"""  "8& )"!)" )"  )"V $ "$)-(, %&  &    (2"""% " & "  "8 ""*" "  "  "( " "  """ "$"""  "0& "!" "  ",C'C3@C *CJ'''3@' *'R* :   r/rTcj[U[5(aURU5$[U[5(aNURn[U[5(a-URU5nX2LaU$[UR U5$[ RS[U5R5 U$)NzfSerializer %s does not support msgpack allowlist. Strict msgpack deserialization will not be enforced.) rrwith_msgpack_allowlistrrVcipherloggerwarningtyper()rVrinner updated_inners r0rrs%+,,++O<<%,--  e/ 0 0!88IM% &u||]C C NN ? U  Lr/c\rSrSrSrSrg)EmptyChannelErrorizeRaised when attempting to get the value of a channel that hasn't been updated for the first time yet.r&N)r(r)r*r+r,r.r&r/r0rrs  r/rc*USRS5$)zGet checkpoint ID. configurable checkpoint_id)rB)rIs r0get_checkpoint_idrs . ! % %o 66r/c .UR5VVs0sH/up#U[U[5(aURSS5OU_M1 nnnUR S5UR S54HnU(dM UR5H}upSXQ;d U[ ;dUR S5(aM,[U[5(aURSS5X'MW[U[[[45(dMyX1U'M M U$s snnf)9Get checkpoint metadata in a backwards-compatible manner.rrJr__) rArr#replacerBEXCLUDED_METADATA_KEYS startswithr boolfloat)rIrJrDr5objkeys r0get_checkpoint_metadatars NN$$DA jC&8&8199Xr "a?$  :& >(BC iikFC#)?"?3>>RVCWCWAs## ! (B 7 AT5122 ! "D Os5DcJ[X5nSU;aURS5 U$)rrQ)rpop)rIrJcheckpoint_metadatas r0$get_serializable_checkpoint_metadatar s,2&C&&) r/> r~r checkpoint_nscheckpoint_maplanggraph_nodelanggraph_pathlanggraph_steplanggraph_triggerslanggraph_checkpoint_nsc SSKJnJn [[[ [ SS95UR UR5R5000/SS9$)Nrdatetimetimezoner clock_seq)r5r6r7r8r:r;r>r<) rr r3LATEST_VERSIONr#rnowutc isoformatrs r0empty_checkpointr.sJ+   ur" # << % / / 1  r/)r6c SSKJnJn URUR5R 5nUcUSnO80nUR 5H"upXS;aMU R 5Xx'M$ [[UU=(d [[US95UUSUSURS/5SS 9$![a Mvf=f) z+Create a checkpoint for the given channels.rrNr8r:r r;r>r?) rr r rrrArCrr3r r#rrB) rCrr!r6rr r7valuesrDr5s r0create_checkpointr=s, hll # - - /B,-NN$DA#566 LLN %   +UT*+#$67 1 nn_b9  %  sB66 CC)rCr3rr3)rVrrrrr)rIrr str | None)rIrrJrrr)rr3) rCr3rz$Mapping[str, ChannelProtocol] | Noner!r r6rrr3)@ __future__rr@loggingcollections.abcrrrrrtypingr r r r r rlangchain_core.runnablesrtyping_extensionsrlanggraph.checkpoint.base.idrlanggraph.checkpoint.serde.baserr$langgraph.checkpoint.serde.encryptedr#langgraph.checkpoint.serde.jsonplusr langgraph.checkpoint.serde.typesrrrrrr rr#rtuple PendingWrite getLoggerr(rrdictr9r3rErGrOrTr ExceptionrrrrWRITES_IDX_MAPrr rrr&r/r0r&s" RR4).WDB CeS!S#s]#    8 $0%0fsC#I--.D 5j5)6b'!*bJ 0K(  7  &8* &8YIr62F  ( 2     r/