Go Dockerfile Example

Dockerfile

# Dockerfile for basic Go application example
# 
# Assumptions
# - There is a project dir
# - Inside the project dir, there is the path src/main 
# - The project's *.go files are located in src/main
# - The project's name is "myapp"

FROM golang:1.11.0-stretch AS packager

RUN mkdir -p /opt/build/bin
WORKDIR /opt/build
ENV GOPATH /opt/build

COPY . .

# Install all dependencies listed in *.go import
RUN go get ./...

# Statically build all libraries and find all *.go files and compile them into a single executable
RUN CGO_ENABLED=0; \
    GOOS=linux; \
    go build -a -installsuffix cgo -ldflags '-extldflags "-static"' -o bin/myapp $(find src/main | grep -i .go)

# --

FROM golang:1.11.0-stretch AS runtime

RUN mkdir -p /opt/app
WORKDIR /opt/app

COPY --from=packager /opt/build/bin/myapp .

RUN chmod +x /opt/app/myapp
ENTRYPOINT ["/opt/app/myapp"]