Dockerfile.static

from alpine:3.16 as gomods

copy . /src/
run cd /src/ && find -type f \! \( -name go.work -o -name go.mod -o -name go.sum \) -exec rm {} +

from golang:1.19.2-alpine3.16 as build

# install dependencies
run apk add --update --no-cache \
    gcc musl-dev \
    linux-headers

# build static dependencies
run apk add bison flex make
# - libnl3
workdir /deps/libnl-3
run wget -O libnl3.tar.gz https://github.com/thom311/libnl/releases/download/libnl3_7_0/libnl-3.7.0.tar.gz
run tar zxvf libnl3.tar.gz --strip-components=1
run ./configure --prefix=/usr --sysconfdir=/etc --enable-cli=no --disable-shared
run make && make install

workdir /src

# go mod args
arg GOPROXY
arg GONOSUMDB

# cache dependencies, they don't change as much as the code
copy --from=gomods /src/ /src/
run go mod download

# test and build

add . ./
#run go test ./...
run go install -trimpath \
      -ldflags "-extldflags '-static -pthread'" \
      ./cmd/...

# the real image
from scratch
entrypoint ["/bin/kpng"]
copy --from=build /go/bin/kpng /bin/