dockerfile

FROM golang:1.20 AS build-stage

# Set destination for COPY
WORKDIR /

# Download Go modules
COPY go.mod go.sum ./
RUN go mod download

# Copy the source code. Note the slash at the end, as explained in
# https://docs.docker.com/engine/reference/builder/#copy
COPY . ./

# Build
RUN CGO_ENABLED=0 GOOS=linux go build -o /airplay-music-watcher

# Deploy the application binary into a lean image
FROM alpine/curl AS build-release-stage

WORKDIR /

COPY --from=build-stage /airplay-music-watcher /airplay-music-watcher

# Optional:
# To bind to a TCP port, runtime parameters must be supplied to the docker command.
# But we can document in the Dockerfile what ports
# the application is going to listen on by default.
# https://docs.docker.com/engine/reference/builder/#expose
EXPOSE 5353

# Run
USER root:root
VOLUME [ "/config" ]

ENTRYPOINT ["/airplay-music-watcher", "/config/config.json"]