Arquillian Run Modes

Question

I'm trying to wrap my head around Arquillian and am just not fundamentally understanding the difference between in-container mode vs. as-client mode.

My understanding is that, with Arquillian/ShrinkWrap:

• You create an archive that only contains the components you want to integrate and test with
• You stream this in-memory archive to an actual container (deploying it)
• You run the archive as a test inside the container
• You make an assertion about what will happen as a result of that test

So, from my perspective, everything just "feels" like it would always be in-container, since the tests are always executing inside a container.

Please help me understand the differences between these two modes and what types of integration tests both modes are suited for. Bonus points for providing a concrete code example (and not the vague ones straight from the Reference Guide!) that explain why/how you run the tests in both modes. Thanks in advance!

Answer 1

• in-container: use for white box, integration testing
• as-client: use for black box, functional testing

i.e., for UI/functional testing ("as" the role of a "client" using the app in production) use as-client mode with @RunAsClient. For true integration testing (testing dependencies between classes where you need internal "white box" knowledge about the app itself), using in-container mode.

In both cases ShrinkWrap and Arquillian deploy your in-memory archive (JAR/WAR/EAR) directly to the configured container (via a JBoss-homegrown streaming protocol), however when tests are run in different modes they have different access to the container depending on the test mode.