FROM --platform=$BUILDPLATFORM golang:1.16.0-alpine3.13 AS builder
# ex. amd64
ARG TARGETARCH
# ex. linux/amd64
ARG BUILDPLATFORM

RUN apk update && \
    apk add --no-cache git ca-certificates make tzdata gcc libc-dev && \
    apk add --no-cache -X http://dl-cdn.alpinelinux.org/alpine/edge/testing cfssl && \
    update-ca-certificates

ENV USER=appuser
ENV UID=10001
ENV GID=10001
WORKDIR /data

RUN addgroup \
    --gid "${GID}" \
    "${USER}" && \
    adduser \
    --disabled-password \
    --gecos "" \
    --home "/nonexistent" \
    --shell "/sbin/nologin" \
    --no-create-home \
    --uid "${UID}" \
    -G "${USER}" \
    "${USER}"

COPY Makefile .
COPY certs/ certs/
RUN make gen-cert

COPY go.mod .
COPY go.sum .
RUN make dependencies

ARG BINARYNAME="poller"
# ARG BINARYNAME="weather"

COPY . .
# RUN make build-$BINARYNAME GOARCH=$TARGETARCH GOOS=$(echo $BUILDPLATFORM | cut -d'/' -f1) LDFLAGS='-extldflags="-static"'
RUN make build-$BINARYNAME GOARCH=$TARGETARCH GOOS=$(echo $BUILDPLATFORM | cut -d'/' -f1) GOBUILDFLAGS="-a -tags netgo -installsuffix netgo"

FROM scratch

USER appuser:appuser

COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo
COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
COPY --from=builder /etc/passwd /etc/passwd
COPY --from=builder /etc/group /etc/group
COPY --from=builder --chown=appuser:appuser /data/bin/* /go/bin/poller
COPY --from=builder --chown=appuser:appuser /data/certs/out/weather* /go

WORKDIR /go
ENTRYPOINT ["/go/bin/poller"]