Dockerfile

# Build the manager binary
FROM golang:1.22.6 AS builder
ARG TARGETOS
ARG TARGETARCH

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 ./ .

# Build
# the GOARCH has not a default value to allow the binary 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 -a -o combi ./cmd/combi

# Use distroless as minimal base image to package the manager binary
# Refer to https://github.com/GoogleContainerTools/distroless for more details
FROM debian:bullseye-slim
WORKDIR /
COPY --from=builder /workspace/combi .
RUN apt update && \
    apt install --yes openssh-client && \
    mkdir -p ~/.ssh && \
    ssh-keyscan -H github.com >> ~/.ssh/known_hosts && \
    echo 'export SSH_KNOWN_HOSTS=~/.ssh/known_hosts' >> ~/.bashrc

ENTRYPOINT ["/combi"]