adding_tests.md

Adding tests

If you are developing knative you may need to add or change:

• e2e tests
• Conformance tests

Both tests can use our test library.

Reviewers of conformance and e2e tests (i.e. OWNERS) are responsible for the style and quality of the resulting tests. In order to not discourage contributions, when style change are required, the reviewers can make the changes themselves.

Presubmit tests

presubmit-tests.sh is the entry point for both the end-to-end tests and the conformance tests

This script, and consequently, the e2e and conformance tests will be run before every code submission. You can run these tests manually with:

test/presubmit-tests.sh

Test library

In the test dir you will find several libraries in the test package you can use in your tests.

You can:

• Use common test flags
• Get access to client objects
• Make requests against deployed services
• Poll Knative Serving resources
• Verify resource state transitions
• Generate boilerplate CRDs
• Ensure test cleanup

Use common test flags

These flags are useful for running against an existing cluster, making use of your existing environment setup.

By importing github.com/knative/serving/test you get access to a global variable called test.Flags which holds the values of the command line flags.

imagePath := strings.Join([]string{test.Flags.DockerRepo, image}, "/"))

See e2e_flags.go.

Get access to client objects

To initialize client objects that you can use the command line flags that describe the environment:

func setup(t *testing.T) *test.Clients {
	clients, err := test.NewClients(kubeconfig, cluster, namespaceName)
	if err != nil {
		t.Fatalf("Couldn't initialize clients: %v", err)
	}
	return clients
}

The Clients struct contains initialized clients for accessing:

• Kubernetes objects
• Routes
• Configurations
• Revisions

For example, to create a Route:

_, err = clients.Routes.Create(test.Route(namespaceName, routeName, configName))

And you can use the client to clean up Route and Configuration resources created by your test:

func tearDown(clients *test.Clients) {
	if clients != nil {
		clients.Delete([]string{routeName}, []string{configName})
	}
}

See clients.go.

Make requests against deployed services

After deploying (i.e. creating a Route and a Configuration) an endpoint will not be ready to serve requests right away. To poll a deployed endpoint and wait for it to be in the state you want it to be in (or timeout) use WaitForEndpointState:

err = test.WaitForEndpointState(clients.Kube, resolvableDomain, updatedRoute.Status.Domain, namespaceName, routeName, func(body string) (bool, error) {
    return body == expectedText, nil
})
if err != nil {
    t.Fatalf("The endpoint for Route %s at domain %s didn't serve the expected text \"%s\": %v", routeName, updatedRoute.Status.Domain, expectedText, err)
}

This function makes use of the environment flag resolvableDomain to determine if the ingress should be used or the domain should be used directly.

See request.go.

Poll Knative Serving resources

After creating Knative Serving resources or making changes to them, you will need to wait for the system to realize those chnages. You can use the Knative Serving CRD polling methods to poll the resources until they get into the desired state or time out.

These functions use the kubernetes wait package. To poll they use PollImmediate and the return values of the function you provide behave the same as ConditionFunc: a bool to indicate if the function should stop or continue polling, and an error to indicate if there has been an error.

For example, you can poll a Configuration object to find the name of the Revision that was created for it:

var revisionName string
err := test.WaitForConfigurationState(clients.Configs, configName, func(c *v1alpha1.Configuration) (bool, error) {
    if c.Status.LatestCreatedRevisionName != "" {
        revisionName = c.Status.LatestCreatedRevisionName
        return true, nil
    }
    return false, nil
})

See crd_polling.go.

Verify resource state transitions

To use the polling functions you must provide a function to check the state. Some of the expected transition states (as defined in the Knative Serving spec) are expressed in functions in states.go.

For example when a Revision has been created, the system will start the resources required to actually serve it, and then the Revision object will be updated to indicate it is ready. This can be polled with test.IsRevisionReady:

err := test.WaitForRevisionState(clients.Revisions, revisionName, test.IsRevisionReady(revisionName))
if err != nil {
    t.Fatalf("Revision %s did not become ready to serve traffic: %v", revisionName, err)
}

Once the Revision is created, all traffic for a Route should be routed to it. This can be polled with test.AllRouteTrafficAtRevision:

err = test.WaitForRouteState(clients.Routes, routeName, test.AllRouteTrafficAtRevision(routeName, revisionName))
if err != nil {
    t.Fatalf("The Route %s was not updated to route traffic to the Revision %s: %v", routeName, revisionName, err)
}

See states.go.

Generate boilerplate CRDs

Your tests will probably need to create Route and Configuration objects. You can use the existing boilerplate to describe them.

For example to create a Configuration object that uses a certain docker image:

_, err := clients.Configs.Create(test.Configuration(namespaceName, configName, imagePath))
if err != nil {
    return err
}

Please expand these functions as more use cases are tested.

See crd.go.

Ensure test cleanup

To ensure your test is cleaned up, you should defer cleanup to execute after your test completes and also ensure the cleanup occurs if the test is interrupted:

defer tearDown(clients)
test.CleanupOnInterrupt(func() { tearDown(clients) })

See cleanup.go.