Adds a directed edge src -[edge_type]-> dst or replaces it if the same triple already exists. Both endpoints must already exist; writing an edge to a missing node fails with invalid_argument.engine.graph_edge_endpoint. Weight defaults to 1.0 and must not be negative. Once the graph’s ontology is frozen, the edge type and its endpoint object types are validated against the declared link types.

Successful mutations return an acknowledgement that identifies the affected target, the mutation effect, and commit facts when the operation changed stored state.

Examples

Add a typed edge between two nodes.

CLI

$ strata graph create social
$ strata graph add-node social alice
$ strata graph add-node social bob
$ strata graph add-edge social alice knows bob
$ strata graph get-edge social alice knows bob

Wire

{"graph":"social","type":"graph_create"}
{"graph":"social","node_id":"alice","type":"graph_add_node"}
{"graph":"social","node_id":"bob","type":"graph_add_node"}
{"dst":"bob","edge_type":"knows","graph":"social","src":"alice","type":"graph_add_edge"}
{"dst":"bob","edge_type":"knows","graph":"social","src":"alice","type":"graph_get_edge"}

Parameters

Name	Type	Required	Description
dst	string	yes	Destination node id.
edge_type	string	yes	Edge type.
graph	string	yes	Graph name.
properties	any	no	Optional edge properties.
src	string	yes	Source node id.
weight	number	no	Optional edge weight. Defaults to 1.0.

Plus the optional scope: branch and space (default to the session branch and the "default" space).

Returns

MutationAck<GraphEdgeWrite>.

Errors

• failed_precondition.engine.runtime_closed
• not_found.engine.branch
• invalid_argument.engine.product_space
• invalid_argument.engine.graph_name
• not_found.engine.graph
• invalid_argument.engine.graph_node_id
• invalid_argument.engine.graph_edge_type
• invalid_argument.engine.graph_edge_type_reserved
• invalid_argument.engine.graph_edge_weight
• invalid_argument.engine.graph_edge_endpoint
• invalid_argument.engine.graph_properties
• invalid_argument.engine.graph_properties_too_large
• failed_precondition.engine.graph_negative_weight
• failed_precondition.engine.graph_ontology_edge_type
• failed_precondition.engine.graph_ontology_endpoint_type

Invocation

• CLI: strata graph add-edge
• Wire type: graph_add_edge