test(e2e): verify delivery retry limits

Signed-off-by: kahirokunn <okinakahiro@gmail.com>

Author: kahirokunn

.github/workflows/kind-e2e.yaml

@@ -9,24 +9,27 @@ on:
 jobs:
 
   ko-resolve:
-    name: e2e tests
+    name: e2e tests (${{ matrix.eventing-version }})
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false # Keep running if one leg fails.
       matrix:
-        k8s-version:
-        - v1.34.3
-
-        eventing-version:
-        - knative-v1.21.0
-
-        # Map between K8s and KinD versions.
-        # This is attempting to make it a bit clearer what's being tested.
-        # See: https://github.com/kubernetes-sigs/kind/releases/tag/v0.29.0
         include:
+        # Keep testing the oldest supported Eventing release, and build the
+        # upstream main commit that introduced DeliverySpec.BackoffMax.
+        - k8s-version: v1.34.3
+          kind-version: v0.31.0
+          kind-image-sha: sha256:08497ee19eace7b4b5348db5c6a1591d7752b164530a36f855cb0f2bdcbadd48
+          eventing-version: knative-v1.21.0
+          eventing-source: release
+          delivery-features-e2e: false
         - k8s-version: v1.34.3
           kind-version: v0.31.0
           kind-image-sha: sha256:08497ee19eace7b4b5348db5c6a1591d7752b164530a36f855cb0f2bdcbadd48
+          eventing-version: main-973bbbc1
+          eventing-source: source
+          eventing-ref: 973bbbc1f791c274578360917c7d492828b48cb0
+          delivery-features-e2e: true
     env:
       KO_DOCKER_REPO: kind.local
       SYSTEM_NAMESPACE: knative-eventing
@@ -48,6 +51,14 @@ jobs:
     - name: Check out code
       uses: actions/checkout@v4
 
+    - name: Check out Knative Eventing source
+      if: matrix.eventing-source == 'source'
+      uses: actions/checkout@v4
+      with:
+        repository: knative/eventing
+        ref: ${{ matrix.eventing-ref }}
+        path: .eventing-source
+
     - name: Install KinD
       env:
         KIND_VERSION: ${{ matrix.kind-version }}
@@ -111,7 +122,8 @@ jobs:
         kubectl get pods -n kube-system -l k8s-app=kube-dns
         kubectl logs -n kube-system -l k8s-app=kube-dns
 
-    - name: Install Knative Eventing
+    - name: Install released Knative Eventing
+      if: matrix.eventing-source == 'release'
       run: |
         set -x
 
@@ -120,6 +132,23 @@ jobs:
         kubectl apply --filename https://github.com/knative/eventing/releases/download/${{ matrix.eventing-version }}/eventing-core.yaml
         kubectl apply --filename https://github.com/knative/eventing/releases/download/${{ matrix.eventing-version }}/mt-channel-broker.yaml
 
+    - name: Build and install Knative Eventing source
+      if: matrix.eventing-source == 'source'
+      working-directory: .eventing-source
+      run: |
+        set -x
+
+        ko apply --platform=linux/amd64 -f ./config/
+        ko apply --platform=linux/amd64 -f ./config/brokers/mt-channel-broker/
+
+    - name: Enable delivery features
+      if: matrix.delivery-features-e2e
+      run: |
+        kubectl patch configmap config-features \
+          --namespace knative-eventing \
+          --type merge \
+          --patch '{"data":{"delivery-backoff-max":"enabled","delivery-retryafter":"enabled"}}'
+
     - name: Install
       run: |
         set -x
@@ -140,6 +169,8 @@ jobs:
         kubectl get pods --all-namespaces
 
     - name: Run e2e Tests
+      env:
+        EVENTING_DELIVERY_FEATURES_E2E: ${{ matrix.delivery-features-e2e }}
       run: |
         set -x
 
@@ -189,4 +220,3 @@ jobs:
         SLACK_TITLE: Periodic e2e for Nats on kind on (${{ matrix.k8s-version }}, ${{ matrix.eventing-version }}) failed.
         SLACK_MESSAGE: |
           For detailed logs: https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}
-