Combine CRD install verification into 1 job, and update k8s versions (#3448)

* Validate CRDs against latest Kubernetes versions

Add Kubernetes v1.19 and v1.20 series images, and consolidate the job
into a single file to reduce repetition.

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Ignore job if the changes are only site/design

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Fix codespell error

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Cache Velero binary for reuse on workers

This will cache the Velero binary based on the PR number and a SHA256 of
the generated binary.

This way, the runners testing each version of Kubernetes do not need to
build it independently.

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Fix GitHub event access

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Wrap output path in quotes

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Move code checkout to build step

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Also cache go modules

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Fix syntax issues

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Download cached binary on each node

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

* Use cached go modules on main CI

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

.github/workflows/crds-verify-k8s-1-16-9.yaml

@@ -1,20 +0,0 @@
-name: "Verify Velero CRDs on k8s 1.16.9"
-on: [pull_request]
-
-jobs:
-  kind:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@master
-    - uses: engineerd/setup-kind@v0.5.0
-      with:
-          image: "kindest/node:v1.16.9"
-    - name: Testing
-      run: |
-        kubectl cluster-info
-        kubectl get pods -n kube-system
-        kubectl version
-        echo "current-context:" $(kubectl config current-context)
-        echo "environment-kubeconfig:" ${KUBECONFIG}
-        make local
-        ./_output/bin/linux/amd64/velero install --crds-only --dry-run -oyaml | kubectl apply -f -

.github/workflows/crds-verify-k8s-1-17-0.yaml

@@ -1,20 +0,0 @@
-name: "Verify Velero CRDs on k8s 1.17"
-on: [pull_request]
-
-jobs:
-  kind:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@master
-    - uses: engineerd/setup-kind@v0.5.0
-      with:
-          image: "kindest/node:v1.17.0"
-    - name: Testing
-      run: |
-        kubectl cluster-info
-        kubectl get pods -n kube-system
-        kubectl version
-        echo "current-context:" $(kubectl config current-context)
-        echo "environment-kubeconfig:" ${KUBECONFIG}
-        make local
-        ./_output/bin/linux/amd64/velero install --crds-only --dry-run -oyaml | kubectl apply -f -

.github/workflows/crds-verify-k8s-1-18-4.yaml

@@ -1,20 +0,0 @@
-name: "Verify Velero CRDs on k8s 1.18.4"
-on: [pull_request]
-
-jobs:
-  kind:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@master
-    - uses: engineerd/setup-kind@v0.5.0
-      with:
-          image: "kindest/node:v1.18.4"
-    - name: Testing
-      run: |
-        kubectl cluster-info
-        kubectl get pods -n kube-system
-        kubectl version
-        echo "current-context:" $(kubectl config current-context)
-        echo "environment-kubeconfig:" ${KUBECONFIG}
-        make local
-        ./_output/bin/linux/amd64/velero install --crds-only --dry-run -oyaml | kubectl apply -f -

.github/workflows/crds-verify-kind.yaml

@@ -0,0 +1,86 @@
+name: "Verify Velero CRDs across k8s versions"
+on:
+  pull_request:
+    # Do not run when the change only includes these directories.
+    paths-ignore:
+      - "site/**"
+      - "design/**"
+
+jobs:
+  # Build the Velero CLI once for all Kubernetes versions, and cache it so the fan-out workers can get it.
+  build-cli:
+    runs-on: ubuntu-latest
+    steps:
+      # Look for a CLI that's made for this PR
+      - name: Fetch built CLI
+        id: cache
+        uses: actions/cache@v2
+        env:
+          cache-name: cache-velero-cli
+        with:
+          path: ./_output/bin/linux/amd64/velero
+          # The cache key a combination of the current PR number, and a SHA256 hash of the Velero binary
+          key: velero-${{ github.event.pull_request.number }}-${{ hashFiles('./_output/bin/linux/amd64/velero') }}
+          # This key controls the prefixes that we'll look at in the cache to restore from
+          restore-keys: |
+            velero-${{ github.event.pull_request.number }}-
+
+      - name: Fetch cached go modules
+        uses: actions/cache@v2
+        if: steps.cache.outputs.cache-hit != 'true'
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
+      - name: Check out the code
+        uses: actions/checkout@v2
+        if: steps.cache.outputs.cache-hit != 'true'
+
+      # If no binaries were built for this PR, build it now.
+      - name: Build Velero CLI
+        if: steps.cache.outputs.cache-hit != 'true'
+        run: |
+          make local
+
+  # Check the common CLI against all kubernetes versions
+  crd-check:
+    needs: build-cli
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        # Latest k8s versions. There's no series-based tag, nor is there a latest tag.
+        k8s:
+          - 1.15.12
+          - 1.16.15
+          - 1.17.17
+          - 1.18.15
+          - 1.19.7
+          - 1.20.2
+    # All steps run in parallel unless otherwise specified.
+    # See https://docs.github.com/en/actions/learn-github-actions/managing-complex-workflows#creating-dependent-jobs
+    steps:
+      - name: Fetch built CLI
+        id: cache
+        uses: actions/cache@v2
+        env:
+          cache-name: cache-velero-cli
+        with:
+          path: ./_output/bin/linux/amd64/velero
+          # The cache key a combination of the current PR number, and a SHA256 hash of the Velero binary
+          key: velero-${{ github.event.pull_request.number }}-${{ hashFiles('./_output/bin/linux/amd64/velero') }}
+          # This key controls the prefixes that we'll look at in the cache to restore from
+          restore-keys: |
+            velero-${{ github.event.pull_request.number }}-
+      - uses: engineerd/setup-kind@v0.5.0
+        with:
+          image: "kindest/node:v${{ matrix.k8s }}"
+      - name: Install CRDs
+        run: |
+          kubectl cluster-info
+          kubectl get pods -n kube-system
+          kubectl version
+          echo "current-context:" $(kubectl config current-context)
+          echo "environment-kubeconfig:" ${KUBECONFIG}
+          ./_output/bin/linux/amd64/velero install --crds-only --dry-run -oyaml | kubectl apply -f -

.github/workflows/pr-ci-check.yml

@@ -1,14 +1,20 @@
 name: Pull Request CI Check
 on: [pull_request]
 jobs:
-
   build:
     name: Run CI
     runs-on: ubuntu-latest
     steps:
-
       - name: Check out the code
         uses: actions/checkout@v2
 
+      - name: Fetch cached go modules
+        uses: actions/cache@v2
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
       - name: Make ci
         run: make ci