neo4j-procedure-template

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= Neo4j Procedure Template :branch: 5.x :root: https://github.com/neo4j-examples/neo4j-procedure-template/blob/{branch}/src

This project is an example you can use to build user defined procedures, functions and aggregation functions in Neo4j. It contains two procedures, for reading and updating a full-text index.

To try this out, simply clone this repository and have a look at the source and test code (including Test-Server-Setup).

[Note] This project requires a Neo4j {branch}.x dependency.

== User Defined Procedure

The user defined procedure allows you to get the incoming and outgoing relationships for a given node.

See link:{root}/main/java/example/GetRelationshipTypes.java[GetRelationshipTypes.java] and the link:{root}/test/java/example/GetRelationshipTypesTests.java[GetRelationshipTypesTests.java].

[source,cypher]

MATCH (n:Person) CALL example.getRelationshipTypes(n) YIELD outgoing, incoming RETURN outgoing, incoming;

== User Defined Function

The user defined function is a simple join function that joins a list of strings using a delimiter.

See link:{root}/main/java/example/Join.java[Join.java] and the link:{root}/test/java/example/JoinTest.java[JoinTest.java].

[source,cypher]

RETURN example.join(['A','quick','brown','fox'],' ') as sentence

== User Defined Aggregation Function

The aggregation function example.last returns the last row of an aggregation.

[source,cypher]

MATCH (n:Person) WITH n ORDER BY n.born WITH example.last(n) as last RETURN last

See link:{root}/main/java/example/Last.java[Last.java] and the link:{root}/test/java/example/LastTest.java[LastTest.java].

== Building

This project uses maven, to build a jar-file with the procedure in this project, simply package the project with maven:

mvn clean package

This will produce a jar-file,target/procedure-template-1.0.0-SNAPSHOT.jar, that can be deployed in the plugin directory of your Neo4j instance.

== License

Apache License V2, see LICENSE