Dockerfile

# Build the manager binary
FROM golang:1.23 AS builder
ARG TARGETOS
ARG TARGETARCH

WORKDIR /workspace

RUN --mount=type=cache,target=/go/pkg/mod/ \
    --mount=type=cache,target=/root/.cache/go-build \
    --mount=type=bind,source=go.sum,target=go.sum \
    --mount=type=bind,source=go.mod,target=go.mod \
    go mod download -x

COPY cmd/main.go cmd/main.go
COPY api/ api/
COPY internal/ internal/
COPY util/ util/
COPY go.mod go.sum ./

# 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 --mount=type=cache,target=/go/pkg/mod/ \
    --mount=type=cache,target=/root/.cache/go-build \
    CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build -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
WORKDIR /
COPY --from=builder /workspace/manager .
USER 65532:65532

ENTRYPOINT ["/manager"]