Cross compile

Dockerfile

@@ -1,5 +1,15 @@
-# Build the manager binary
-FROM golang:1.20 as builder
+FROM --platform=$BUILDPLATFORM golang:1.20-alpine AS builder
+
+RUN apk add --update --no-cache gcc libc-dev
+
+ARG TARGETARCH
+ARG BUILDARCH
+
+RUN if [ "${TARGETARCH}" = "arm64" ] && [ "${BUILDARCH}" != "arm64" ]; then \
+        wget -c https://musl.cc/aarch64-linux-musl-cross.tgz -O - | tar -xzvv --strip-components 1 -C /usr; \
+    elif [ "${TARGETARCH}" = "amd64" ] && [ "${BUILDARCH}" != "amd64" ]; then \
+        wget -c https://musl.cc/x86_64-linux-musl-cross.tgz -O - | tar -xzvv --strip-components 1 -C /usr; \
+    fi
 
 WORKDIR /workspace
 # Copy the Go Modules manifests
@@ -17,12 +27,16 @@ COPY internal/ internal/
 
 ARG VERSION
 
-# Build
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags "-X github.com/strangelove-ventures/cosmos-operator/internal/version.version=$VERSION" -a -o manager .
+RUN if [ "${TARGETARCH}" = "arm64" ] && [ "${BUILDARCH}" != "arm64" ]; then \
+        export CC=aarch64-linux-musl-gcc CXX=aarch64-linux-musl-g++;\
+    elif [ "${TARGETARCH}" = "amd64" ] && [ "${BUILDARCH}" != "amd64" ]; then \
+        export CC=x86_64-linux-musl-gcc CXX=x86_64-linux-musl-g++; \
+    fi; \
+    GOOS=linux GOARCH=$TARGETARCH CGO_ENABLED=1 LDFLAGS='-linkmode external -extldflags "-static"'; \
+    go build -ldflags "-X github.com/strangelove-ventures/cosmos-operator/internal/version.version=$VERSION $LDFLAGS" -a -o manager .
 
-# 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
+# Build final image from scratch
+FROM scratch
 
 LABEL org.opencontainers.image.source=https://github.com/strangelove-ventures/cosmos-operator
 

local.Dockerfile

@@ -0,0 +1,33 @@
+FROM golang:1.20-alpine AS builder
+
+RUN apk add --update --no-cache gcc libc-dev
+
+WORKDIR /workspace
+# Copy the Go Modules manifests
+COPY go.mod go.mod
+COPY go.sum 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 *.go .
+COPY api/ api/
+COPY controllers/ controllers/
+COPY internal/ internal/
+
+ARG VERSION
+
+RUN CGO_ENABLED=1 LDFLAGS='-linkmode external -extldflags "-static"'; \
+    go build -ldflags "-X github.com/strangelove-ventures/cosmos-operator/internal/version.version=$VERSION $LDFLAGS" -a -o manager .
+
+# Build final image from scratch
+FROM scratch
+
+LABEL org.opencontainers.image.source=https://github.com/strangelove-ventures/cosmos-operator
+
+WORKDIR /
+COPY --from=builder /workspace/manager .
+USER 65532:65532
+
+ENTRYPOINT ["/manager"]