feat: support multi-arch builds of telegraf-operator (#69)

Author: Wojciech Kocjan

.circleci/config.yml

@@ -10,7 +10,8 @@ workflows:
       - container_image:
           filters:
             branches:
-              only: master
+              only:
+                - master
   container-image-release:
     jobs:
       - container_image_release:
@@ -77,28 +78,48 @@ jobs:
             - /go/pkg/mod
           when: always
   container_image:
-    docker:
-      - image: docker:stable-git
+    # using a full VM is needed to build multi-arch container images
+    machine:
+      image: ubuntu-2004:202107-02
     steps:
       - checkout
-      - setup_remote_docker
       - run:
           name: Docker build and push using SHA
           command: |
+            export DOCKER_BUILDKIT=1
             IMAGE="quay.io/influxdb/telegraf-operator"
-            docker build --no-cache -t "$IMAGE:$CIRCLE_SHA1" .
             docker login -u "$QUAY_USER" -p "$QUAY_PASS" quay.io
-            docker push "$IMAGE:$CIRCLE_SHA1"
+
+            # create a new builder to support multi-arch images as the default builder doesn't support it
+            docker buildx create --name "multiarch" || true
+            docker buildx use "multiarch"
+
+            # build image
+            docker buildx build \
+              --output=type=registry \
+              --platform linux/amd64,linux/arm64,linux/arm/v7 \
+              --tag "$IMAGE:$CIRCLE_SHA1" \
+              --file Dockerfile.multi-arch .
   container_image_release:
-    docker:
-      - image: docker:stable-git
+    # using a full VM is needed to build multi-arch container images
+    machine:
+      image: ubuntu-2004:202107-02
     steps:
       - checkout
-      - setup_remote_docker
       - run:
           name: Docker build and push using release tag
           command: |
+            export DOCKER_BUILDKIT=1
             IMAGE="quay.io/influxdb/telegraf-operator"
-            docker build --no-cache -t "$IMAGE:$CIRCLE_TAG" .
             docker login -u "$QUAY_USER" -p "$QUAY_PASS" quay.io
-            docker push "$IMAGE:$CIRCLE_TAG"
+
+            # create a new builder to support multi-arch images as the default builder doesn't support it
+            docker buildx create --name "multiarch" || true
+            docker buildx use "multiarch"
+
+            # build image
+            docker buildx build \
+              --output=type=registry \
+              --platform linux/amd64,linux/arm64,linux/arm/v7 \
+              --tag "$IMAGE:$CIRCLE_TAG" \
+              --file Dockerfile.multi-arch .

Dockerfile

@@ -3,17 +3,16 @@ FROM golang:1.16 as builder
 
 WORKDIR /workspace
 # Copy the Go Modules manifests
-COPY go.mod go.mod
-COPY go.sum go.sum
+COPY go.mod go.sum ./
 # cache deps before building and copying source so that we don't need to re-download as much
 # and so that source changes don't invalidate our downloaded layer
 RUN go mod download
 
-# Copy the go source
+# Copy the go source, build script and run it
+# NOTE: please ensure that file list to copy is synced with Dockerfile.multi-arch
 COPY main.go sidecar.go handler.go class_data.go errors.go watcher.go updater.go ./
-
-# Build
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 GO111MODULE=on go build -a -o manager *.go
+COPY scripts/build-manager.sh /build-manager.sh
+RUN /build-manager.sh
 
 # Use distroless as minimal base image to package the manager binary
 # Refer to https://github.com/GoogleContainerTools/distroless for more details

Dockerfile.multi-arch

@@ -0,0 +1,26 @@
+# Build the manager binary
+FROM --platform=$BUILDPLATFORM golang:1.16 as builder
+
+WORKDIR /workspace
+# Copy the Go Modules manifests
+COPY go.mod go.sum ./
+# cache deps before building and copying source so that we don't need to re-download as much
+# and so that source changes don't invalidate our downloaded layer
+RUN go mod download
+
+# Copy the go source, build script and run it
+# NOTE: please ensure that file list to copy is synced with Dockerfile
+COPY main.go sidecar.go handler.go class_data.go errors.go watcher.go updater.go ./
+COPY scripts/build-manager.sh /build-manager.sh
+ARG TARGETPLATFORM
+ARG BUILDPLATFORM
+RUN /build-manager.sh $TARGETPLATFORM $BUILDPLATFORM
+
+# Use distroless as minimal base image to package the manager binary
+# Refer to https://github.com/GoogleContainerTools/distroless for more details
+FROM gcr.io/distroless/static:nonroot
+WORKDIR /
+COPY --from=builder /workspace/manager .
+USER nonroot:nonroot
+
+ENTRYPOINT ["/manager"]

scripts/build-manager.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+
+export CGO_ENABLED=0
+export GO111MODULE=on
+export GOOS=linux
+
+# default to building amd64 binary, same as prior to multi-arch support
+TARGETPLATFORM="${1:-linux/amd64}"
+
+# default to building same platform as the target one
+BUILDPLATFORM="${2:-}"
+
+if [ "${TARGETPLATFORM}" = "linux/amd64" ] ; then
+  export GOARCH=amd64
+elif [ "${TARGETPLATFORM}" = "linux/arm64" ] ; then
+  export GOARCH=arm64
+elif [ "${TARGETPLATFORM}" = "linux/arm/v7" ] ; then
+  export GOARCH=arm
+else
+  echo >&2 "Unknown TARGETPLATFORM: \"${TARGETPLATFORM}\""
+  exit 1
+fi
+
+echo "Compiling telegraf-operator binary for $GOOS / $GOARCH (from $TARGETPLATFORM)"
+if [ "$BUILDPLATFORM" != "" ] ; then
+  echo "  (using $BUILDPLATFORM for compilation)"
+fi
+
+go build -a -o manager *.go