Dockerfile

# Build the manager binary
FROM golang:1.26.1@sha256:c42e4d75186af6a44eb4159dcfac758ef1c05a7011a0052fe8a8df016d8e8fb9 AS builder
ARG TARGETOS
ARG TARGETARCH
ARG VERSION=devel

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 (relies on .dockerignore to filter)
COPY . .

# Build
# the GOARCH has no default value to allow the binary to be built according to the host where the command
# was called. For example, if we call make docker-build in a local env which has the Apple Silicon M1 SO
# the docker BUILDPLATFORM arg will be linux/arm64 when for Apple x86 it will be linux/amd64. Therefore,
# by leaving it empty we can ensure that the container and binary shipped on it will have the same platform.
RUN CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build -ldflags "-w -s -X main.version=${VERSION}" -a -o manager cmd/main.go

# 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@sha256:e3f945647ffb95b5839c07038d64f9811adf17308b9121d8a2b87b6a22a80a39
WORKDIR /
COPY --from=builder /workspace/manager .
USER 65532:65532

ENTRYPOINT ["/manager"]