Unable to define a conditional edge

[jindalAnuj]

Checked other resources

• I added a very descriptive title to this issue.
• I searched the LangChain documentation with the integrated search.
• I used the GitHub search to find a similar question and didn't find it.
• I am sure that this is a bug in LangChain rather than my code.

Example Code

    class WorkFlow():
	def __init__(self):
		nodes = Nodes()
		workflow = StateGraph(PersonState)
		workflow.add_node("userInput", nodes.userInput)
		workflow.add_node("text2PersonInfo", nodes.text2PersonInfo)
		workflow.add_node("personInfoValidate", nodes.personInfoValidate)
		workflow.add_node("missingDataAgent", nodes.missingDataAgent)
		workflow.set_entry_point("userInput")
		workflow.add_edge('userInput', 'text2PersonInfo')
		workflow.add_edge('text2PersonInfo', 'personInfoValidate')
		workflow.add_conditional_edges(
			"personInfoValidate",
			nodes.personInfoValidate,
			{
				"incomplete": "missingDataAgent",
				"end": END
			}
		)
		self.app = workflow.compile()

 Traceback (most recent call last):
  File "/opt/homebrew/Cellar/python@3.10/3.10.14/Frameworks/Python.framework/Versions/3.10/lib/python3.10/runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/opt/homebrew/Cellar/python@3.10/3.10.14/Frameworks/Python.framework/Versions/3.10/lib/python3.10/runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "/Users/jindal/AppDevelopment/30DaysofAI/LLMHandsOn/lang_graph/main.py", line 15, in <module>
    app.invoke({})
  File "/Users/jindal/Library/Caches/pypoetry/virtualenvs/llm-handson-m_vF4p_v-py3.10/lib/python3.10/site-packages/langgraph/pregel/__init__.py", line 1171, in invoke
    for chunk in self.stream(
  File "/Users/jindal/Library/Caches/pypoetry/virtualenvs/llm-handson-m_vF4p_v-py3.10/lib/python3.10/site-packages/langgraph/pregel/__init__.py", line 774, in stream
    _panic_or_proceed(done, inflight, step)
  File "/Users/jindal/Library/Caches/pypoetry/virtualenvs/llm-handson-m_vF4p_v-py3.10/lib/python3.10/site-packages/langgraph/pregel/__init__.py", line 1260, in _panic_or_proceed
    raise exc
  File "/opt/homebrew/Cellar/python@3.10/3.10.14/Frameworks/Python.framework/Versions/3.10/lib/python3.10/concurrent/futures/thread.py", line 58, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/Users/jindal/Library/Caches/pypoetry/virtualenvs/llm-handson-m_vF4p_v-py3.10/lib/python3.10/site-packages/langchain_core/runnables/base.py", line 2499, in invoke
    input = step.invoke(
  File "/Users/jindal/Library/Caches/pypoetry/virtualenvs/llm-handson-m_vF4p_v-py3.10/lib/python3.10/site-packages/langgraph/utils.py", line 88, in invoke
    ret = context.run(self.func, input, **kwargs)
  File "/Users/jindal/Library/Caches/pypoetry/virtualenvs/llm-handson-m_vF4p_v-py3.10/lib/python3.10/site-packages/langgraph/graph/graph.py", line 74, in _route
    destinations = [self.ends[r] for r in result]
  File "/Users/jindal/Library/Caches/pypoetry/virtualenvs/llm-handson-m_vF4p_v-py3.10/lib/python3.10/site-packages/langgraph/graph/graph.py", line 74, in <listcomp>
    destinations = [self.ends[r] for r in result]
TypeError: unhashable type: 'dict'

[tool.poetry.dependencies]
python = ">=3.10.0,<3.11"
ollama = "^0.1.8"
load-dotenv = "^0.1.0"
langgraph = "0.0.45"
langchain = "^0.1.17"

Error Message and Stack Trace (if applicable)

No response

Description

whenever i remove conditional node it works fine

System Info

System Information

OS: Darwin
OS Version: Darwin Kernel Version 22.2.0: Fri Nov 11 02:04:44 PST 2022; root:xnu-8792.61.2~4/RELEASE_ARM64_T8103
Python Version: 3.10.14 (main, Mar 19 2024, 21:46:16) [Clang 15.0.0 (clang-1500.1.0.2.5)]

Package Information

langchain_core: 0.1.52
langchain: 0.1.17
langchain_community: 0.0.37
langsmith: 0.1.54
langchain_openai: 0.0.5
langchain_text_splitters: 0.0.1
langgraph: 0.0.45

Packages not installed (Not Necessarily a Problem)

The following packages were not found:

langserve

[hinthornw]

What does personInfoValidate look like?

[jindalAnuj]

        ask_for = []
        status = "end"
        print('personInfoValidate',state)
        # Check if fields are empty 
        # for field, value in state["person"].dict().items():
        #     if value in [None, "", 0]:  # You can add other 'empty' conditions as per your requirements
        #         print(f"Field '{field}' is empty.")
        #         ask_for.append(f'{field}')
        # if ask_for:
        #     status = "incomplete"
        return {
            **state,
            "status": status,
            # "ask_for": ask_for
        }

some commented code for testing

[dylanlap98]

I'm having this same problem.

Pip versions:
...
langgraph 0.0.46
langchain-core 0.1.52
...

Code:

from langgraph.graph import StateGraph, END
from typing import TypedDict, Annotated
 
class GraphState(TypedDict):
    num_steps: int
    email: str
    classification: str
    technology: str
 
def graph_printer(state):
    print("-- GRAPH PRINTER --")
    print(f"classification: {state['classification']}")
    print(f"technology: {state['technology']}")
    print(f"num_steps: {state['num_steps']}")
    print()
    return
 
def router_1(state):    #: List[BaseMessage]
    #technology = state['technology']
 
    ## LLM call would go here (for now simulate response):
    technology = "Sagemaker"
 
    print(technology)
    if 'aws' in technology.lower():
        print("RUNNING AWS\n")
        return "aws"
        #return {"technology": "aws"} # trying other formats to fix
    else:
        print("RUNNING OTHER\n")
        return "other"
        #return {"technology": "other"}
        #return {"input": "other"}
 
def lane_switch(state):
    print(" --- RAN LANE SWITCH --- ")
    print()
    return
   
testgraph = StateGraph(GraphState)
 
testgraph.add_node("state_printer_1", graph_printer)
testgraph.add_node("router", router_1)
testgraph.add_node("state_printer_2", graph_printer)
testgraph.add_node("lane_switcher", lane_switch) # only run if aws
testgraph.set_entry_point("state_printer_1")
testgraph.add_edge("state_printer_1", "router")
testgraph.add_conditional_edges(
    "router",
    router_1,
    {
        "aws": "lane_switcher",
        "other": "state_printer_2"
    }
)
testgraph.add_edge("lane_switcher", "state_printer_2")
testgraph.add_edge("state_printer_2", END)
 

testapp = testgraph.compile()
 
email  = "HELLO THERE AWS USER! Thanks." # simulate email
inputs = {"email": email, "num_steps": 0}
testapp.invoke(inputs)

Output error:

langgraph.errors.InvalidUpdateError: Expected dict, got other

Hoping this example helps..
-Dylan LaPierre

[DevTimBo]

You can fix this by adding a next_step to your graph instead of just passing the route function to the conditional edge

I hope this helps

[TechKemon]

I'm having this same error

[ArmaanMistry]

I got the same error, but I resolved it by applying a lambda function within the conditional edges to check the relevant conditions. This approach worked for me.

Note: The check_medical and check_greeting functions return boolean values, while the other functions return the updated state.

class AgentState(TypedDict):
    user_input: str
    medical_intent: bool
    greeting_intent: bool
    response: str

class Agent:
    def __init__(self, model):
        self.conversation_history = []
        self.graph = StateGraph(AgentState)

        self.graph.add_node("ask_user", self.ask_user)
        self.graph.add_node("check_medical", self.check_medical)
        self.graph.add_node("ask_doctor", self.ask_doctor)
        self.graph.add_node("check_greeting", self.check_greeting)
        self.graph.add_node("ans_greeting", self.ans_greeting)
        self.graph.add_node("static_idk_msg", self.static_idk_msg)

        self.graph.add_conditional_edges("check_medical", lambda state: state['medical_intent'], {True: "ask_doctor", False: "check_greeting"})
        self.graph.add_conditional_edges("check_greeting", lambda state: state['greeting_intent'], {True: "ans_greeting", False: "static_idk_msg"})

        self.graph.add_edge("ask_user", "check_medical")
        self.graph.add_edge("ask_doctor", END)
        self.graph.add_edge("ans_greeting", END)
        self.graph.add_edge("static_idk_msg", END)

        self.graph.set_entry_point("ask_user")

        self.chatbot = self.graph.compile()
        self.model = model

# (other functions...)

I hope this helps!