Build ta on the host and copy it into the container image (open-telem…

…etry#2293)

.github/workflows/publish-target-allocator.yaml

@@ -11,18 +11,35 @@ on:
       - 'v*'
   workflow_dispatch:
 
+env:
+  PLATFORMS: linux/amd64,linux/arm64,linux/s390x,linux/ppc64le
+
 jobs:
   publish:
     runs-on: ubuntu-22.04
 
     steps:
       - uses: actions/checkout@v4
 
+      - uses: actions/setup-go@v4
+        with:
+          go-version: '~1.21.3'
+          cache-dependency-path: 'cmd/otel-allocator/go.sum'
+
+      # TODO: We're currently not using this. Should we?
       - name: Read version
         run: |
           echo "VERSION=$(git describe --tags | sed 's/^v//')" >> $GITHUB_ENV
           echo "VERSION_DATE=$(date -u +'%Y-%m-%dT%H:%M:%SZ')" >> $GITHUB_ENV
 
+      - name: Build the binary for each supported architecture
+        run: |
+          for platform in $(echo $PLATFORMS | tr "," "\n"); do
+            arch=${platform#*/}
+            echo "Building target allocator for $arch"
+            make targetallocator ARCH=$arch
+          done
+
       - name: Docker meta
         id: meta
         uses: docker/metadata-action@v5
@@ -69,11 +86,8 @@ jobs:
         uses: docker/build-push-action@v5
         with:
           context: cmd/otel-allocator
-          platforms: linux/amd64,linux/arm64,linux/s390x,linux/ppc64le
+          platforms: ${{ env.PLATFORMS }}
           push: true
-          build-args: |
-            VERSION=${{ env.VERSION }}
-            VERSION_DATE=${{ env.VERSION_DATE }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
           cache-from: type=local,src=/tmp/.buildx-cache

Makefile

@@ -108,6 +108,10 @@ test: generate fmt vet ensure-generate-is-noop envtest
 manager: generate fmt vet
 	CGO_ENABLED=0 GOOS=$(GOOS) GOARCH=$(ARCH) go build -o bin/manager_${ARCH} -ldflags ${LD_FLAGS} main.go
 
+# Build target allocator binary
+targetallocator:
+	cd cmd/otel-allocator && CGO_ENABLED=0 GOOS=$(GOOS) GOARCH=$(ARCH) go build -a -installsuffix cgo -o bin/targetallocator_${ARCH} .
+
 # Run against the configured Kubernetes cluster in ~/.kube/config
 .PHONY: run
 run: generate fmt vet manifests
@@ -254,8 +258,9 @@ container-target-allocator-push:
 	docker push ${TARGETALLOCATOR_IMG}
 
 .PHONY: container-target-allocator
-container-target-allocator:
-	docker buildx build  --load --platform linux/${ARCH} -t ${TARGETALLOCATOR_IMG} cmd/otel-allocator
+container-target-allocator: GOOS = linux
+container-target-allocator: targetallocator
+	docker build -t ${TARGETALLOCATOR_IMG} cmd/otel-allocator
 
 .PHONY: container-operator-opamp-bridge
 container-operator-opamp-bridge:

cmd/otel-allocator/Dockerfile

@@ -1,29 +1,19 @@
-# Build the otel-allocator binary
-FROM golang:1.21-alpine as builder
-
-WORKDIR /app
+# Get CA certificates from the Alpine package repo
+FROM alpine:3.18 as certificates
 
 RUN apk --no-cache add ca-certificates
 
-# Copy go mod and sum files
-COPY go.mod go.sum ./
-
-RUN go mod download
-
-COPY . .
-
-# Build the Go app
-RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o main .
-
-######## Start a new stage from scratch #######
+# Start a new stage from scratch
 FROM scratch
 
+ARG TARGETARCH
+
 WORKDIR /root/
 
-# Copy the certs from the builder
-COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+# Copy the certs
+COPY --from=certificates /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
 
-# Copy the pre-built binary file from the previous stage
-COPY --from=builder /app/main .
+# Copy binary built on the host
+COPY bin/targetallocator_${TARGETARCH} ./main
 
 ENTRYPOINT ["./main"]