[SOLVED] Neo4j: unit testing the bolt driver properly

Neo4j: unit testing the bolt driver properly

I am adding the Neo4j Bolt driver to my application just following the http://neo4j.com/developer/java/:

import org.neo4j.driver.v1.*;

Driver driver = GraphDatabase.driver( "bolt://localhost", AuthTokens.basic( "neo4j", "neo4j" ) );

Session session = driver.session();
session.run( "CREATE (a:Person {name:'Arthur', title:'King'})" );

StatementResult result = session.run( "MATCH (a:Person) WHERE a.name = 'Arthur' RETURN a.name AS name, a.title AS title" );

while ( result.hasNext() )

{
    Record record = result.next();
    System.out.println( record.get( "title" ).asString() + " " + record.get("name").asString() );
}
session.close();
driver.close();

However, always from the official documentation unit testing is made using:

GraphDatabaseService db = new TestGraphDatabaseFactory()
            .newImpermanentDatabaseBuilder()

So if I want to test in some way the code above, I have to replace the GraphDatabase.driver( "bolt://localhost",...) with the GraphDatabaseService from the test. How can I do that? I cannot extract any sort of in-memory driver from there as far as I can see.

Solution

The Neo4j JDBC has a class called Neo4jBoltRule for unit testing. It is a junit rule starting/stopping an impermanent database together with some configuration to start bolt.

The rule class uses dynamic port assignment to prevent test failure due to running multiple tests in parallel (think of your CI infrastructure).

An example of a unit test using that rule class is available at https://github.com/neo4j-contrib/neo4j-jdbc/blob/master/neo4j-jdbc-bolt/src/test/java/org/neo4j/jdbc/bolt/SampleIT.java