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

This pull-request has been approved by: akurinnoy, tolusha
Once this PR has been reviewed and has the lgtm label, please assign dkwon17 for approval. For more information see the Code Review Process.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[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.