Visualize your graph

from typing import Literal

from typing_extensions import TypedDict

from langgraph.graph import END, START, StateGraph


class State(TypedDict):
    value: int


def node1(state: State):
    return {"value": state["value"] + 1}


def node2(state: State):
    return {"value": state["value"] * 2}


def router(state: State) -> Literal["node2", "__end__"]:
    if state["value"] < 10:
        return "node2"
    return END


app = (
    StateGraph(State)
    .add_node("node1", node1)
    .add_node("node2", node2)
    .add_edge(START, "node1")
    .add_conditional_edges("node1", router)
    .add_edge("node2", "node1")
    .compile()
)

print(app.get_graph().draw_mermaid())

---
config:
  flowchart:
    curve: linear
---
graph TD;
	__start__([<p>__start__</p>]):::first
	node1(node1)
	node2(node2)
	__end__([<p>__end__</p>]):::last
	__start__ --> node1;
	node1 -.-> __end__;
	node1 -.-> node2;
	node2 --> node1;
	classDef default fill:#f2f0ff,line-height:1.2
	classDef first fill-opacity:0
	classDef last fill:#bfb6fc

from IPython.display import Image, display

display(Image(app.get_graph().draw_mermaid_png()))

import nest_asyncio
from IPython.display import Image, display
from langchain_core.runnables.graph import CurveStyle, MermaidDrawMethod, NodeStyles

nest_asyncio.apply()  # Required for Jupyter Notebook to run async functions

display(
    Image(
        app.get_graph().draw_mermaid_png(
            curve_style=CurveStyle.LINEAR,
            node_colors=NodeStyles(first="#ffdfba", last="#baffc9", default="#fad7de"),
            wrap_label_n_words=9,
            output_file_path=None,
            draw_method=MermaidDrawMethod.PYPPETEER,
            background_color="white",
            padding=10,
        )
    )
)

from IPython.display import Image, display

try:
    display(Image(app.get_graph().draw_png()))
except ImportError:
    print(
        "Install pygraphviz to draw graphs with Graphviz: `pip install pygraphviz`. "
        "You also need the Graphviz system binary: https://graphviz.org/download/"
    )