[SOLVED] Incapable of running unit tests because of CREATE INDEX and CREATE CONSTRAINT

Incapable of running unit tests because of CREATE INDEX and CREATE CONSTRAINT

I've developed a module for Neo4j using Graphaware package. As a part of my module, I want to make sure that some indices and/or constraints are present in the database. To this end, I use BaseTxDrivenModule.initialize method to run a couple of Cypher statements:

@Override
public void initialize(GraphDatabaseService database)
{
    database.execute("CREATE CONSTRAINT ON (n:`Label`) ASSERT n.`id` IS UNIQUE;");
    database.execute("CREATE INDEX ON n:`Label2`(`id`) IS UNIQUE;");
}

These statements run successfully in production when I deploy the module in a server instance of Neo4j. But when I want to run the unit tests, as a part of build process, the execution hangs and never finishes. And when I omit the initialize method, it goes on without any error.

The worst part is that I have to build the package like: mvn package -Dmaven.test.skip=true or it won't build anything.

So my question is, why? And how can I fix this problem?

Here's a sample project demonstrating the issue:

https://github.com/ziadloo/test_neo4j_module

Just clone it and run mvn package and you'll see that the tests never finish.

Solution

There is no guarantee that the Runtime is started during your test, you'll have to assert it by invoking the waitUntilStarted method.

@Before
    public void setUp() {
        database = new TestGraphDatabaseFactory()
            .newImpermanentDatabaseBuilder()
            .loadPropertiesFromFile(this.getClass().getClassLoader().getResource("neo4j-module.conf").getPath())
            .newGraphDatabase();

        getRuntime(database).waitUntilStarted();

        registerShutdownHook(database);
    }

I would suggest you take a look at some test cases in the neo4j-uuid module for eg.