Have tests for kcctl

[gunnarmorling]

Currently, no tests exist for kcctl at all. We should add tests for the different commands, so to avoid regressions down the road. As part of this task, we need to

• Understand how PicoCLI applications are tested; is their any guidance in their docs?
• Set up the infrastructure for integration tests via Testcontainers; we'll need to start up ZooKeeper, Kafka, and Kafka Connect for testing kcctl; as inspiration or starting point, here's a Docker Compose file which shows the required components; as a test connector, the built-in file connector could probably be used

[SiddiqueAhmad]

I setup the container resources class took help from debezium facing few issues, but we will do it

[karim-elngr]

The picocli documentation provide some helpful insights into writing tests

@QuarkusTest
class PauseConnectorCommandTest {

    final PrintStream originalOut = System.out;
    final PrintStream originalErr = System.err;
    final ByteArrayOutputStream out = new ByteArrayOutputStream();
    final ByteArrayOutputStream err = new ByteArrayOutputStream();

    @Inject
    CommandLine commandLine;

    @BeforeEach
    public void setUpStreams() {
        out.reset();
        err.reset();
        System.setOut(new PrintStream(out));
        System.setErr(new PrintStream(err));
    }

    @AfterEach
    public void restoreStreams() {
        System.setOut(originalOut);
        System.setErr(originalErr);
    }

    @Test
    void run() {

        String[] args = "pause connector connector-1".split(" ");

        commandLine.execute(args);

        assertEquals("", out.toString());
        assertEquals("", err.toString());
    }
}

[gunnarmorling]

Thanks, @karim-elngr, so essentially we'd just do assertions on the output stream we've set before. Makes sense. We can throw AssertJ into the mix for more expressive assertions.

@SiddiqueAhmad, ok, excellent. Seems the way forward to having some first integration tests is pretty clear then.

[karim-elngr]

I think this is worth mentioning that SDK man uses a very interesting BDD approach for testing, I wonder if there is a common approach to test cli tools

https://github.com/sdkman/sdkman-cli/blob/master/src/test/resources/features/java_installation.feature

[gunnarmorling]

Hey @karim-elngr, out curiosity, did you have any chance to make some progress here?

[karim-elngr]

Hi @gunnarmorling I was taking some time off before starting my new role, I will try to get some progress going next week!

[SiddiqueAhmad]

hi @karim-elngr I tried the code snippet above but I am losing context when command is being executed, #85 have more detail

[gunnarmorling]

That's done now thanks to a heroic effort by @iabudiab 🎉 .