Support for service integration tests about lagom

[jroper]

Four people +1'ing within 10 minutes of each other only counts as one vote.

[TimPigden]

For those people who have +'d it recently. I would point out that for me this requirement has largely disappeared. The reason being that I routinely and completely mock every service with an in-memory map or maps to emulate the persistence and simple scala collection processing to emulate the repository actions. I then subject the mock service to all the testing that the full service gets within the sub-project. Finally any cross-service testing can use either an entire set of mocks or the service under test as a service plus the others all as mocks. This works fine so long as your services are effectively only communicating via their path apis. It won't work though if you're using Kafka. But if you're not it's definitely worth consideration as you can test all sorts of complex things and run tests in a couple of seconds that take far longer when having to instantiate real services.

[sallareznov]

No schedule for the support in the API? 🤔

[TimPigden]

Please! Is it good form to write +1?

[emarx]

Looks like this issue has been dormant for a while - is there a plan for integration tests?

[odwrotnie]

+1!

[deepakmehra10]

+1

[aklikic]

+1

[phil9987]

+1

[luq555]

+1

[AdamJanasek]

+1

[Rath-san]

+1

[ignasi35]

It won't work though if you're using Kafka.

That's an interesting scenario. @TimPigden have you tried using Broker Testing tools provided in Lagom to expand your mocks?

I am assuming there's a ServiceA under test that has a mocked ServiceB. ServiceA publishes messages to topicA and ServiceB publishes on topicB. Finally, both ServiceA and ServiceB subscribe to each other's topics.
(This is not too different from ItemService and BidService in online-auction-javasample app)
Then, when testing ServiceA you may be able to expect a message being published on topicA and, as a consequence, send a mocked response via topicB. Finally, you can eventually assert that ServiceA received and processed the message on topicB.

[TimPigden]

@ignasi35 Ah. That's interesting. Haven't hit that yet as not currently using Kafka (although that's expected to change).

[nserfontein]

+1

[odwrotnie]

Do you know the ETA?

[odwrotnie]

How do you mock a service and the service locator in tests? Is there any example?

[TimMoore]

Discussing in https://discuss.lightbend.com/t/mocking-services-in-a-test/1189/4

[gabizou]

Starting to write my own integration tests and running into this limitation after trying to find out why they weren't running 👀.
I can understand this is all backlogged (I've my own gripes about Maven and the plugin, considering taking up the time to try and wrangle a Gradle variant). Short of writing a bunch of scripts to test after launching, I'd hope to see some better integration testing for CI management.

[solarmosaic-kflorence]

We use https://github.com/testcontainers/testcontainers-scala for this purpose. There are several ways you could stand up a replacement for the service under test -- you could start up a mock service based on an OpenAPI spec for example. Since we use Pact, we stand up a stub service containing stubs for all service dependencies prior to the tests running and it works quite well.