arcade-mcp/examples/langchain/langgraph_with_user_auth.py
Sam Partee 140f4eca17
Langchain arcade 1.2 (#282)
- **New Class Structure**: Introduced `ToolManager` and
`AsyncToolManager` classes (`ArcadeToolManager` is deprecated)
- **Async Support**: Full async implementation for modern LangChain
applications
- **Better Tool Management**: New methods for adding individual tools
and toolkits
- **CI/CD**: for langchain_arcade


## Upgrade Changes

```python
# Old pattern
manager = ArcadeToolManager(api_key="...")
tools = manager.get_tools(toolkits=["Google"])

# New pattern
manager = ToolManager(api_key="...")
manager.init_tools(toolkits=["Google"])
tools = manager.to_langchain()
```

Now supports underscores vs dots in tool names for better model
compatibility.
2025-03-10 18:52:06 -07:00

107 lines
3.7 KiB
Python

import os
# Import necessary classes and modules
from langchain_arcade import ToolManager
from langchain_openai import ChatOpenAI
from langgraph.checkpoint.memory import MemorySaver
from langgraph.graph import END, START, MessagesState, StateGraph
from langgraph.prebuilt import ToolNode
arcade_api_key = os.environ["ARCADE_API_KEY"]
# Initialize the tool manager and fetch tools
manager = ToolManager(api_key=arcade_api_key)
manager.init_tools(toolkits=["Github"])
# convert to langchain tools and use interrupts for auth
tools = manager.to_langchain(use_interrupts=True)
# Initialize the prebuilt tool node
tool_node = ToolNode(tools)
# Create a language model instance and bind it with the tools
model = ChatOpenAI(model="gpt-4o")
model_with_tools = model.bind_tools(tools)
#### Workflow ####
# Function to invoke the model and get a response
def call_agent(state: MessagesState):
messages = state["messages"]
response = model_with_tools.invoke(messages)
# Return the updated message history
return {"messages": [response]}
# Function to determine the next step in the workflow based on the last message
def should_continue(state: MessagesState):
if state["messages"][-1].tool_calls:
for tool_call in state["messages"][-1].tool_calls:
if manager.requires_auth(tool_call["name"]):
return "authorization"
return "tools" # Proceed to tool execution if no authorization is needed
return END # End the workflow if no tool calls are present
# Function to handle authorization for tools that require it
def authorize(state: MessagesState, config: dict):
user_id = config["configurable"].get("user_id")
for tool_call in state["messages"][-1].tool_calls:
tool_name = tool_call["name"]
if not manager.requires_auth(tool_name):
continue
auth_response = manager.authorize(tool_name, user_id)
if auth_response.status != "completed":
# Prompt the user to visit the authorization URL
print(f"Visit the following URL to authorize: {auth_response.url}")
# wait for the user to complete the authorization
# and then check the authorization status again
manager.wait_for_auth(auth_response.id)
if not manager.is_authorized(auth_response.id):
# node interrupt?
raise ValueError("Authorization failed")
return {"messages": []}
if __name__ == "__main__":
# Build the workflow graph using StateGraph
workflow = StateGraph(MessagesState)
# Add nodes (steps) to the graph
workflow.add_node("agent", call_agent)
workflow.add_node("tools", tool_node)
workflow.add_node("authorization", authorize)
# Define the edges and control flow between nodes
workflow.add_edge(START, "agent")
workflow.add_conditional_edges("agent", should_continue, ["authorization", "tools", END])
workflow.add_edge("authorization", "tools")
workflow.add_edge("tools", "agent")
# Set up memory for checkpointing the state
memory = MemorySaver()
# Compile the graph with the checkpointer
graph = workflow.compile(checkpointer=memory)
# Define the input messages from the user
inputs = {
"messages": [
{
"role": "user",
"content": "Star arcadeai/arcade-ai on github",
}
],
}
# Configuration with thread and user IDs for authorization purposes
config = {"configurable": {"thread_id": "4", "user_id": "user@example.comm"}}
# Run the graph and stream the outputs
for chunk in graph.stream(inputs, config=config, stream_mode="values"):
# Pretty-print the last message in the chunk
chunk["messages"][-1].pretty_print()