FROM golang:1.20 as builder
COPY vapid.go /opt/vapid.go
WORKDIR /opt
RUN go mod init vapid.go && go mod tidy
RUN CGO_ENABLED=0 go build -ldflags "-s -w" -o /vapid /opt/vapid.go

FROM alpine:3.18

RUN apk add --no-cache openldap-passwd-pbkdf2 apache2-utils pwgen opendkim-utils coreutils
COPY dkim-key.sh /dkim-key.sh
COPY --from=builder /vapid /vapid
RUN chmod +x /vapid