mirror of
https://github.com/langchain-ai/langgraph.git
synced 2026-09-08 18:57:52 +02:00
serialize/deserialize pandas with pickle fallback (#5057)
This commit is contained in:
@@ -473,6 +473,23 @@ If the checkpointer is used with asynchronous graph execution (i.e. executing th
|
||||
When checkpointers save the graph state, they need to serialize the channel values in the state. This is done using serializer objects.
|
||||
`langgraph_checkpoint` defines [protocol][langgraph.checkpoint.serde.base.SerializerProtocol] for implementing serializers provides a default implementation ([JsonPlusSerializer][langgraph.checkpoint.serde.jsonplus.JsonPlusSerializer]) that handles a wide variety of types, including LangChain and LangGraph primitives, datetimes, enums and more.
|
||||
|
||||
#### Serialization with `pickle`
|
||||
|
||||
The default serializer, [`JsonPlusSerializer`][langgraph.checkpoint.serde.jsonplus.JsonPlusSerializer], uses ormsgpack and JSON under the hood, which is not suitable for all types of objects.
|
||||
|
||||
If you want to fallback to pickle for objects not currently supported by our msgpack encoder (such as Pandas dataframes),
|
||||
you can use the `pickle_fallback` argument of the `JsonPlusSerializer`:
|
||||
|
||||
```python
|
||||
from langgraph.checkpoint.memory import MemorySaver
|
||||
from langgraph.checkpoint.serde.jsonplus import JsonPlusSerializer
|
||||
|
||||
# ... Define the graph ...
|
||||
graph.compile(
|
||||
checkpointer=MemorySaver(serde=JsonPlusSerializer(pickle_fallback=True))
|
||||
)
|
||||
```
|
||||
|
||||
#### Encryption
|
||||
|
||||
Checkpointers can optionally encrypt all persisted state. To enable this, pass an instance of [`EncryptedSerializer`][langgraph.checkpoint.serde.encrypted.EncryptedSerializer] to the `serde` argument of any `BaseCheckpointSaver` implementation. The easiest way to create an encrypted serializer is via [`from_pycryptodome_aes`][langgraph.checkpoint.serde.encrypted.EncryptedSerializer.from_pycryptodome_aes], which reads the AES key from the `LANGGRAPH_AES_KEY` environment variable (or accepts a `key` argument):
|
||||
|
||||
Reference in New Issue
Block a user