- **Description:** Currently,
`langchain_core.runnables.graph_mermaid.py` is hardcoded to use
mermaid.ink to render graph diagrams. It would be nice to allow users to
specify a custom URL, e.g. for self-hosted instances of the Mermaid
server.
- **Issue:** [Langchain Forum: allow custom mermaid API
URL](https://forum.langchain.com/t/feature-request-allow-custom-mermaid-api-url/1472)
- **Dependencies:** None
- [X] **Add tests and docs**: Added unit tests using mock requests.
- [X] **Lint and test**: Run `make format`, `make lint` and `make test`.
Minimal example using the feature:
```python
import os
import operator
from pathlib import Path
from typing import Any, Annotated, TypedDict
from langgraph.graph import StateGraph
class State(TypedDict):
messages: Annotated[list[dict[str, Any]], operator.add]
def hello_node(state: State) -> State:
return {"messages": [{"role": "assistant", "content": "pong!"}]}
builder = StateGraph(State)
builder.add_node("hello_node", hello_node)
builder.add_edge("__start__", "hello_node")
builder.add_edge("hello_node", "__end__")
graph = builder.compile()
# Run graph
output = graph.invoke({"messages": [{"role": "user", "content": "ping?"}]})
# Draw graph
Path("graph.png").write_bytes(graph.get_graph().draw_mermaid_png(base_url="https://custom-mermaid.ink"))
```
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
* Remove the `beta` namespace from langchain_core
* Remove the context API (never documented and makes it easier to create
memory leaks). This API was a beta API.
Co-authored-by: Sadra Barikbin <sadraqazvin1@yahoo.com>
This pull request introduces a failing unit test to reproduce the bug
reported in issue #32028.
The test asserts the expected behavior: `BaseCallbackManager.merge()`
should combine `handlers` and `inheritable_handlers` independently,
without mixing them. This test will fail on the current codebase and is
intended to guide the fix and prevent future regressions.
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
Co-authored-by: Mason Daugherty <mason@langchain.dev>
This is better than using a subclass as returning a `property` works
with `ClassWithBetaMethods.beta_property.__doc__`
Co-authored-by: Mason Daugherty <mason@langchain.dev>
Added an id field to the Document passed to filter for
InMemoryVectorStore similarity search. This allows filtering by Document
id and brings the input to the filter in line with the result returned
by the vector similarity search.
---------
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
## Summary
This PR standardizes all text file I/O to use `UTF-8`. This eliminates
OS-specific defaults (e.g. Windows `cp1252`) and ensures consistent,
Unicode-safe behavior across platforms.
## Breaking changes
Users on systems with a default encoding which is not utf-8 may see
decoding errors from the following code paths:
* langchain_core.vectorstores.in_memroy.InMemoryVectorStore.load
* langchain_core.prompts.loading.load_prompt
* `from_template` in AIMessagePromptTemplate,
HumanMessagePromptTemplate, SystemMessagePromptTemplate
## Migration
Change the encoding of files that are encoded with a non utf-8 encoding to utf-8.
