############################
# STEP 1 build executable binary
############################
FROM golang:alpine AS builder

# Install git.
# Git is required for fetching the dependencies.
RUN apk update && apk add --no-cache git

WORKDIR $GOPATH/src/mypackage/myapp/
COPY . .

# Using go get.
RUN go get -d -v

# Build the binary.
RUN go build -o /go/bin/app

# the following command creates single static binaries that can run from scratch
# RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -a -tags netgo -ldflags '-w -extldflags "-static"' -o /go/bin/app *.go

############################
# STEP 2 build a small image
############################
FROM alpine:3.9

# Copy executable
COPY --from=builder /go/bin/app /go/bin/app

# Run the hello binary.
ENTRYPOINT ["/go/bin/app"]