From 499fe10ef2e0df2ec34c37d19584f02d64db1ff5 Mon Sep 17 00:00:00 2001
From: Nuno Campos <nuno@langchain.dev>
Date: Tue, 27 Aug 2024 13:34:50 -0700
Subject: [PATCH] Undo addition of Send.id

---
 .../checkpoint/langgraph/checkpoint/serde/jsonplus.py |  2 +-
 libs/checkpoint/langgraph/checkpoint/serde/types.py   |  1 -
 libs/langgraph/langgraph/constants.py                 | 11 ++++-------
 libs/langgraph/langgraph/pregel/algo.py               |  6 +++---
 libs/langgraph/langgraph/pregel/loop.py               |  1 -
 5 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py b/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py
index e80b9a678..e39a66e76 100644
--- a/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py
+++ b/libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py
@@ -109,7 +109,7 @@ class JsonPlusSerializer(SerializerProtocol):
             return self._encode_constructor_args(obj.__class__, args=[obj.value])
         elif isinstance(obj, SendProtocol):
             return self._encode_constructor_args(
-                obj.__class__, kwargs={"node": obj.node, "arg": obj.arg, "id": obj.id}
+                obj.__class__, kwargs={"node": obj.node, "arg": obj.arg}
             )
         elif isinstance(obj, (bytes, bytearray)):
             return self._encode_constructor_args(
diff --git a/libs/checkpoint/langgraph/checkpoint/serde/types.py b/libs/checkpoint/langgraph/checkpoint/serde/types.py
index fb0055b51..67f59ae89 100644
--- a/libs/checkpoint/langgraph/checkpoint/serde/types.py
+++ b/libs/checkpoint/langgraph/checkpoint/serde/types.py
@@ -50,7 +50,6 @@ class SendProtocol(Protocol):
     # Mirrors langgraph.constants.Send
     node: str
     arg: Any
-    id: str
 
     def __hash__(self) -> int: ...
 
diff --git a/libs/langgraph/langgraph/constants.py b/libs/langgraph/langgraph/constants.py
index 3b322d391..085316333 100644
--- a/libs/langgraph/langgraph/constants.py
+++ b/libs/langgraph/langgraph/constants.py
@@ -1,6 +1,5 @@
 from dataclasses import dataclass
-from typing import Any, Literal, Optional
-from uuid import uuid4
+from typing import Any, Literal
 
 INPUT = "__input__"
 CONFIG_KEY_SEND = "__pregel_send"
@@ -79,9 +78,8 @@ class Send:
 
     node: str
     arg: Any
-    id: Optional[str]
 
-    def __init__(self, /, node: str, arg: Any, id: Optional[str] = None) -> None:
+    def __init__(self, /, node: str, arg: Any) -> None:
         """
         Initialize a new instance of the Send class.
 
@@ -92,13 +90,12 @@ class Send:
         """
         self.node = node
         self.arg = arg
-        self.id = id or str(uuid4())
 
     def __hash__(self) -> int:
-        return hash((self.node, self.arg, self.id))
+        return hash((self.node, self.arg))
 
     def __repr__(self) -> str:
-        return f"Send(node={self.node!r}, arg={self.arg!r}, id={self.id!r})"
+        return f"Send(node={self.node!r}, arg={self.arg!r})"
 
     def __eq__(self, value: object) -> bool:
         return (
diff --git a/libs/langgraph/langgraph/pregel/algo.py b/libs/langgraph/langgraph/pregel/algo.py
index 39ca717b6..2f1589573 100644
--- a/libs/langgraph/langgraph/pregel/algo.py
+++ b/libs/langgraph/langgraph/pregel/algo.py
@@ -291,9 +291,9 @@ def prepare_next_tasks(
             "langgraph_task_idx": len(tasks),
         }
         checkpoint_ns = (
-            f"{parent_ns}{CHECKPOINT_NAMESPACE_SEPARATOR}{packet.node}:{packet.id}"
+            f"{parent_ns}{CHECKPOINT_NAMESPACE_SEPARATOR}{packet.node}"
             if parent_ns
-            else f"{packet.node}:{packet.id}"
+            else packet.node
         )
         task_id = str(
             uuid5(UUID(checkpoint["id"]), json.dumps((checkpoint_ns, metadata)))
@@ -344,7 +344,7 @@ def prepare_next_tasks(
                                 CONFIG_KEY_CHECKPOINTER: checkpointer,
                                 CONFIG_KEY_RESUMING: is_resuming,
                                 "checkpoint_id": checkpoint["id"],
-                                "checkpoint_ns": checkpoint_ns,
+                                "checkpoint_ns": f"{checkpoint_ns}:{task_id}",
                             },
                         ),
                         triggers,
diff --git a/libs/langgraph/langgraph/pregel/loop.py b/libs/langgraph/langgraph/pregel/loop.py
index b4e6d4118..509f6eabc 100644
--- a/libs/langgraph/langgraph/pregel/loop.py
+++ b/libs/langgraph/langgraph/pregel/loop.py
@@ -118,7 +118,6 @@ class PregelLoop:
     checkpoint_config: RunnableConfig
     checkpoint_metadata: CheckpointMetadata
     checkpoint_pending_writes: List[PendingWrite]
-    # (thread_id, checkpoint_ns -> channel_versions)
     checkpoint_previous_versions: dict[str, Union[str, float, int]]
 
     step: int