Add GOARM in Restic builder. Add PR container build action.

Signed-off-by: Xun Jiang <blackpiglet@gmail.com>

.github/workflows/pr-containers.yml

@@ -0,0 +1,37 @@
+name: build Velero containers on Dockerfile change
+
+on:
+  pull_request:
+    branches:
+      - 'main'
+      - 'release-**'
+    paths:
+      - 'Dockerfile'
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+      name: Checkout
+
+    - name: Set up QEMU
+      id: qemu
+      uses: docker/setup-qemu-action@v1
+      with:
+        platforms: all
+
+    - name: Set up Docker Buildx
+      id: buildx
+      uses: docker/setup-buildx-action@v1
+      with:
+        version: latest
+
+    # Although this action also calls docker-push.sh, it is not triggered
+    # by push, so BRANCH and TAG are empty by default. docker-push.sh will
+    # only build Velero image without pushing.
+    - name: Make Velero container without pushing to registry.
+      if: github.repository == 'vmware-tanzu/velero'
+      run: |
+        ./hack/docker-push.sh

Dockerfile

@@ -62,7 +62,8 @@ env CGO_ENABLED=0 \
 COPY . /go/src/github.com/vmware-tanzu/velero
 
 RUN mkdir -p /output/usr/bin && \
-    bash /go/src/github.com/vmware-tanzu/velero/hack/build-restic.sh
+    export GOARM=$(echo "${GOARM}" | cut -c2-) && \
+    /go/src/github.com/vmware-tanzu/velero/hack/build-restic.sh
 
 # Velero image packing section
 FROM gcr.io/distroless/base-debian11@sha256:99133cb0878bb1f84d1753957c6fd4b84f006f2798535de22ebf7ba170bbf434

changelogs/unreleased/5771-blackpiglet

@@ -0,0 +1 @@
+Add PR container build action, which will not push image. Add GOARM parameter.

hack/docker-push.sh

@@ -56,6 +56,18 @@ elif [[ "$triggeredBy" == "tags" ]]; then
     TAG=$(echo $GITHUB_REF | cut -d / -f 3)
 fi
 
+# if both BRANCH and TAG are empty, then it's triggered by PR. Use target branch instead.
+# BRANCH is needed in docker buildx command to set as image tag.
+# When action is triggered by PR, just build container without pushing, so set type to local.
+# When action is triggered by PUSH, need to push container, so set type to registry.
+if [[ -z $BRANCH && -z $TAG ]]; then
+    echo "Test Velero container build without pushing, when Dockerfile is changed by PR."
+    BRANCH="${GITHUB_BASE_REF}-container"
+    OUTPUT_TYPE="local,dest=."
+else
+    OUTPUT_TYPE="registry"
+fi
+
 TAG_LATEST=false
 if [[ ! -z "$TAG" ]]; then
     echo "We're building tag $TAG"
@@ -90,11 +102,9 @@ echo "BUILDX_PLATFORMS: $BUILDX_PLATFORMS"
 
 echo "Building and pushing container images."
 
-# The use of "registry" as the buildx output type below instructs
-# Docker to push the image
 
 VERSION="$VERSION" \
 TAG_LATEST="$TAG_LATEST" \
 BUILDX_PLATFORMS="$BUILDX_PLATFORMS" \
-BUILDX_OUTPUT_TYPE="registry" \
+BUILDX_OUTPUT_TYPE=$OUTPUT_TYPE \
 make all-containers