ARG ARCH

# STEP 1 build executable binary
FROM golang:1.17.1-alpine3.13@sha256:bd3c3710755f637c6ec64b317a22e58f048ddefe622fb03073935ee9073ff99f AS builder-amd64
FROM arm32v7/golang:1.17.1-alpine3.13@sha256:750b25e1c177d21746b2f4eeac941175d44b762fdad0f73b4b51a54ea572fab0 AS builder-arm
FROM arm64v8/golang:1.17.1-alpine3.13@sha256:cef4bfe0462ac7d15bf38c5297d501833c66e0fca1549582c9a02e6e5c11d111 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 git curl && \
    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 alpine:3.14.2@sha256:e1c082e3d3c45cccac829840a25941e679c25d438cc8412c2fa221cf1a824e6a AS base-amd64
FROM arm32v7/alpine:3.14.2@sha256:e12ff876f0075740ed3d7bdf788107ae84c1b3dd6dc98b3baea41088aba5236f AS base-arm
FROM arm64v8/alpine:3.14.2@sha256:b06a5cf61b2956088722c4f1b9a6f71dfe95f0b1fe285d44195452b8a1627de7 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"]