FROM mirror.gcr.io/library/golang:1.21-alpine as build
RUN apk add ca-certificates

WORKDIR /godoor

# pre-copy/cache go.mod for pre-downloading dependencies and only redownloading them in subsequent builds if they change
COPY go.mod go.sum ./
RUN go mod download && go mod verify


COPY . .

ENV GOBUILDLDFLAGS="-linkmode 'external' -extldflags '-static'"
RUN go build -tags netgo .

FROM scratch
WORKDIR /
COPY --from=build /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
COPY --from=build /godoor/godoor /godoor

ENTRYPOINT ["/godoor"]