ARG ARCH

# STEP 1 build executable binary
FROM amd64/golang:1.16.2-alpine3.13@sha256:4aee936562c29840e20ddb14bdbe028f7a7f376f2932096f5bfcc1931ec9f7c1 AS builder-amd64
FROM arm32v7/golang:1.16.2-alpine3.13@sha256:b1d11ae3a57e214620430094f54b37b07d76a7227771a53ea21270902a2f2f21 AS builder-arm
FROM arm64v8/golang:1.16.2-alpine3.13@sha256:8cab145c26bb1d6e0369c53c0c8def3781c218ab7099a879262fd9b5e4ed9197 AS builder-arm64
FROM builder-${ARCH} AS builder

ENV FILTRON_VERSION="v0.2.0"

WORKDIR $GOPATH/src/github.com/asciimoo/filtron

RUN apk upgrade --no-cache && \
    apk add --no-cache tar="1.33-r1" git="2.30.2-r0" curl="7.74.0-r1" && \
    curl -L "https://github.com/asciimoo/filtron/archive/${FILTRON_VERSION}.tar.gz" | tar xvz --strip 1

RUN go get -d -v && gofmt -l ./ && go build .

# STEP 2 build the image including only the binary
FROM amd64/alpine:3.13.3@sha256:4266485e304a825d82c375d3584121b53c802e3540d6b520b212a9f0784d56f5 AS base-amd64
FROM arm32v7/alpine:3.13.3@sha256:20e384223963ef2fd24ec9341eaad4c796673da0e848387e6fe53ee2ec118d0e AS base-arm
FROM arm64v8/alpine:3.13.3@sha256:31605c2bc05b020943d5c20a108f4bfe1af47e0a818e94411041805d1374ab42 AS base-arm64
FROM base-${ARCH}

RUN apk --no-cache add ca-certificates="20191127-r5" && \
    adduser -D -h /usr/local/filtron -s /bin/false filtron filtron

COPY --from=builder /go/src/github.com/asciimoo/filtron/example_rules.json /etc/filtron/rules.json
COPY --from=builder /go/src/github.com/asciimoo/filtron/filtron /usr/local/filtron/filtron

EXPOSE 3000
USER filtron

ENTRYPOINT ["/usr/local/filtron/filtron", "--rules", "/etc/filtron/rules.json"]