langchain_core.runnables.graph.Graph

class langchain_core.runnables.graph.Graph(nodes: ~typing.Dict[str, ~langchain_core.runnables.graph.Node] = <factory>, edges: ~typing.List[~langchain_core.runnables.graph.Edge] = <factory>)

Graph of nodes and edges.

Attributes

nodes
edges

Methods

__init__([nodes, edges])
add_edge(source, target[, data])	Add an edge to the graph and return it.
add_node(data[, id])	Add a node to the graph and return it.
draw_ascii()
draw_png()
extend(graph)	Add all nodes and edges from another graph.
first_node()	Find the single node that is not a target of any edge.
last_node()	Find the single node that is not a source of any edge.
next_id()
print_ascii()
remove_node(node)	Remove a node from the graphm and all edges connected to it.
to_json()	Convert the graph to a JSON-serializable format.
trim_first_node()	Remove the first node if it exists and has a single outgoing edge, ie.
trim_last_node()	Remove the last node if it exists and has a single incoming edge, ie.

Parameters

• nodes (Dict[str, Node]) –

• edges (List[Edge]) –

__init__(nodes: ~typing.Dict[str, ~langchain_core.runnables.graph.Node] = <factory>, edges: ~typing.List[~langchain_core.runnables.graph.Edge] = <factory>) → None

Parameters

• nodes (Dict[str, Node]) –

• edges (List[Edge]) –

Return type

None

add_edge(source: Node, target: Node, data: Optional[str] = None) → Edge

Add an edge to the graph and return it.

Parameters

• source (Node) –

• target (Node) –

• data (Optional[str]) –

Return type

Edge

add_node(data: Union[Type[BaseModel], RunnableType], id: Optional[str] = None) → Node

Add a node to the graph and return it.

Parameters

• data (Union[Type[BaseModel], RunnableType]) –

• id (Optional[str]) –

Return type

Node

draw_ascii() → str

Return type

str

draw_png(output_file_path: str, fontname: Optional[str] = None, labels: Optional[LabelsDict] = None) → None

draw_png(output_file_path: None, fontname: Optional[str] = None, labels: Optional[LabelsDict] = None) → bytes

extend(graph: Graph) → None

Add all nodes and edges from another graph. Note this doesn’t check for duplicates, nor does it connect the graphs.

Parameters

graph (Graph) –

Return type

None

first_node() → Optional[Node]

Find the single node that is not a target of any edge. If there is no such node, or there are multiple, return None. When drawing the graph this node would be the origin.

Return type

Optional[Node]

last_node() → Optional[Node]

Find the single node that is not a source of any edge. If there is no such node, or there are multiple, return None. When drawing the graph this node would be the destination.

Return type

Optional[Node]

next_id() → str

Return type

str

print_ascii() → None

Return type

None

remove_node(node: Node) → None

Remove a node from the graphm and all edges connected to it.

Parameters

node (Node) –

Return type

None

to_json() → Dict[str, List[Dict[str, Any]]]

Convert the graph to a JSON-serializable format.

Return type

Dict[str, List[Dict[str, Any]]]

trim_first_node() → None

Remove the first node if it exists and has a single outgoing edge, ie. if removing it would not leave the graph without a “first” node.

Return type

None

trim_last_node() → None

Remove the last node if it exists and has a single incoming edge, ie. if removing it would not leave the graph without a “last” node.

Return type

None