Play framework - testing data access layer without started application

Question

Is there a way to write tests for the data access objects (DAOs) in play framework 2.x without starting an app?

Tests with fake app are relatively slow even if the database is an in-memory H2 as the docs suggests.

Answer 1

After experiencing similar issues with execution time of tests using FakeAplication I switched to a different approach. Instead of creating one fake app per test I start a real instance of the application and run all my tests against it. With a large test suite there is a big win in total execution time.

http://yefremov.net/blog/fast-functional-tests-play/

Answer 2

For unit testing, a good solution is mocking. If you are using Play 2.4 and above, Mockito is already built in, and you do not have to import mockito separately.

For integration testing, you cannot run tests without fake application, since sometimes your DAOs probably require application context information, for example the information defined in application.conf. In this case, you must setup a FakeApplication with fake application configuration so that DAOs have that information.

This sample repo,https://github.com/luongbalinh/play-mongo/tree/master/test, contains tests at service and controller layers, including both unit tests with Mockito and integration tests. Integration tests for DAOs should be very similar to the service tests. Hopefully, it gives you a hint of how to use Mockito to write DAO tests.