fix: identical endpoint name conflicts

[akurinnoy]

What does this PR do?

What issues does this PR fix or reference?

This PR implements conflict detection and prevention at both the controller and webhook levels.

Is it tested? How?

Same-namespace conflict detection

1. Create test namespace

oc create namespace test-namespace

2. Create first namespace and wait for it to be running.

cat << EOF | oc apply -f -
apiVersion: workspace.devfile.io/v1alpha2
kind: DevWorkspace
metadata:
  name: endpoint-test-1
  namespace: test-namespace
spec:
  started: true
  routingClass: basic
  template:
    components:
      - name: postgresql
        container:
          image: quay.io/fedora/postgresql-12:latest
          endpoints:
            - name: postgresql
              targetPort: 5432
              exposure: internal
              protocol: tcp
              attributes:
                discoverable: true
          env:
            - name: POSTGRESQL_USER
              value: user
            - name: POSTGRESQL_PASSWORD
              value: pass
            - name: POSTGRESQL_ROOT_PASSWORD
              value: root
            - name: POSTGRESQL_DATABASE
              value: db
EOF

oc wait --for=condition=Ready dw/endpoint-test-1 -n test-namespace --timeout=300s

3. Try to create second workspace with same discoverable endpoint name. This operation should fail.

cat << EOF | oc apply -f -
apiVersion: workspace.devfile.io/v1alpha2
kind: DevWorkspace
metadata:
  name: endpoint-test-2
  namespace: test-namespace
spec:
  started: true
  routingClass: basic
  template:
    components:
      - name: postgresql
        container:
          image: quay.io/fedora/postgresql-12:latest
          endpoints:
            - name: postgresql
              targetPort: 5432
              exposure: internal
              protocol: tcp
              attributes:
                discoverable: true
          env:
            - name: POSTGRESQL_USER
              value: user
            - name: POSTGRESQL_PASSWORD
              value: pass
            - name: POSTGRESQL_ROOT_PASSWORD
              value: root
            - name: POSTGRESQL_DATABASE
              value: db
EOF

Expected result:

# "admission webhook "validate-devfile.devworkspace-controller.svc" denied the request: 
# discoverable endpoint 'postgresql' is already in use by workspace 'endpoint-test-1'"

Cross-name isolation

1. Create second namespace

oc create namespace test-namespace-2

2. Create workspace in second namespace with same endpoint name

cat << EOF | oc apply -f -
apiVersion: workspace.devfile.io/v1alpha2
kind: DevWorkspace
metadata:
  name: endpoint-test-1
  namespace: test-namespace-2
spec:
  started: true
  routingClass: basic
  template:
    components:
      - name: postgresql
        container:
          image: quay.io/fedora/postgresql-12:latest
          endpoints:
            - name: postgresql
              targetPort: 5432
              exposure: internal
              protocol: tcp
              attributes:
                discoverable: true
          env:
            - name: POSTGRESQL_USER
              value: user
            - name: POSTGRESQL_PASSWORD
              value: pass
            - name: POSTGRESQL_ROOT_PASSWORD
              value: root
            - name: POSTGRESQL_DATABASE
              value: db
EOF

3. Verify both workspaces are running successfully

oc wait --for=condition=Ready dw/endpoint-test-1 -n test-namespace --timeout=300s
oc wait --for=condition=Ready dw/endpoint-test-1 -n test-namespace-2 --timeout=300s

4. Verify both workspaces have services with the same name

oc get svc postgresql -n test-namespace
oc get svc postgresql -n test-namespace-2

PR Checklist

• E2E tests pass (when PR is ready, comment /test v8-devworkspace-operator-e2e, v8-che-happy-path to trigger)
  • v8-devworkspace-operator-e2e: DevWorkspace e2e test
  • v8-che-happy-path: Happy path for verification integration with Che

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[openshift-ci]

New changes are detected. LGTM label has been removed.

[openshift-ci]

@akurinnoy: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/v14-devworkspace-operator-e2e	654ee01	link	true	/test v14-devworkspace-operator-e2e

Full PR test history. Your PR dashboard.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.

[rohanKanojia]

Minor nitpick: I see that loading objects and setting UID/Namespace are duplicated in most test methods.

Do you think extracting a small helper function for this might improve readability?

[rohanKanojia]

nit, We might consider asserting on the specific error type

Suggested change

	err = handler.validateEndpoints(context.TODO(), workspace)
	err = handler.validateEndpoints(context.TODO(), workspace)
	assert.ErrorAs(t, err, new(*solvers.ServiceConflictError))

[rohanKanojia]

nit, "uid-1" is already a string and SetUID expects a types.UID, which is just a type alias for string

Suggested change

	workspace.SetUID(types.UID("uid-1"))
	workspace.SetUID("uid-1")

[rohanKanojia]

This fallback appears to be unused. I checked usages in code, and all of them seem to populate WorkspaceName.
Is it for backward compatibility of devworkspaces deployed by older versions?

[rohanKanojia]

I tested the PR with abovementioned steps and it seems to work as expected ✔️