README.md

flink-neo4j

Contains Apache Flink specific input and output formats to read Cypher results from Neo4j and write data back in parallel using Cypher batches.

Examples

• Read data from Neo4j into Flink datasets

ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

Neo4jInputFormat<Tuple3<Integer, String, Integer>> input = Neo4jInputFormat
    .buildNeo4jInputFormat()
    .setRestURI("http://localhost:7475/db/data/")
    .setUsername("neo4j")
    .setPassword("password")
    .setCypherQuery("MATCH (n:User) RETURN id(n), n.name, n.born")
    .setConnectTimeout(10_000)
    .setReadTimeout(10_000)
    .finish();

DataSet<Tuple3<Integer, String, Integer>> vertices = env.createInput(input,
    new TupleTypeInfo<Tuple3<Integer, String, Integer>>(
        BasicTypeInfo.INT_TYPE_INFO,
        BasicTypeInfo.STRING_TYPE_INFO,
        BasicTypeInfo.INT_TYPE_INFO
    ));

// do something

• Write data to Neo4j using CREATE statements

ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();

Neo4jOutputFormat<Tuple2<String, Integer>> outputFormat = Neo4jOutputFormat
    .buildNeo4jOutputFormat()
    .setRestURI("http://localhost:7475/db/data/")
    .setConnectTimeout(1_000)
    .setReadTimeout(1_000)
    .setCypherQuery("UNWIND {inserts} AS i CREATE (a:User {name:i.name, born:i.born})")
    .addParameterKey(0, "name")
    .addParameterKey(1, "born")
    .setTaskBatchSize(1000)
    .finish();

env.fromElements(new Tuple2<>("Alice", 1984),new Tuple2<>("Bob", 1976)).output(outputFormat);

env.execute();

Setup

• Add repository and dependency to your maven project

<repositories>
  <repository>
    <id>dbleipzig</id>
    <name>Database Group Leipzig University</name>
    <url>https://wdiserv1.informatik.uni-leipzig.de:443/archiva/repository/dbleipzig/</url>
    <releases>
      <enabled>true</enabled>
    </releases>
    <snapshots>
      <enabled>true</enabled>
    </snapshots>
   </repository>
</repositories>

<dependency>
  <groupId>org.s1ck</groupId>
  <artifactId>flink-neo4j</artifactId>
  <version>0.1-SNAPSHOT</version>
</dependency>

License

Licensed under the Apache License, Version 2.0.