From 51f2acb69bdb863e10cef9c5650802d7c82d3b6e Mon Sep 17 00:00:00 2001
From: Sven Gottwald <svengo@gmx.net>
Date: Fri, 19 Apr 2019 12:29:13 +0200
Subject: [PATCH] Add Dockerfile using multi-stage build

---
 Dockerfile.multistage-build | 39 +++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 Dockerfile.multistage-build

diff --git a/Dockerfile.multistage-build b/Dockerfile.multistage-build
new file mode 100644
index 0000000..9012805
--- /dev/null
+++ b/Dockerfile.multistage-build
@@ -0,0 +1,39 @@
+#
+# Builder
+#
+
+FROM golang:alpine as builder
+
+# use version (for example "v0.3.3") or "master"
+ARG WATCHTOWER_VERSION=master
+
+RUN \
+  apk add --no-cache \
+    alpine-sdk \
+    ca-certificates \
+    git \
+    tzdata && \
+  \
+  mkdir --parents $GOPATH/src/github.com/containrrr && \
+  cd $GOPATH/src/github.com/containrrr && \
+  git clone --branch "${WATCHTOWER_VERSION}" https://github.com/containrrr/watchtower.git && \
+  cd watchtower && \
+  \
+  GO111MODULE=on CGO_ENABLED=0 GOOS=linux go build -a -ldflags '-extldflags "-static"' . && \
+  GO111MODULE=on go test ./... -v
+
+
+#
+# watchtower
+#
+
+FROM scratch
+
+LABEL "com.centurylinklabs.watchtower"="true"
+
+# copy files from other container
+COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+COPY --from=builder /usr/share/zoneinfo /usr/share/zoneinfo
+COPY --from=builder /go/src/github.com/containrrr/watchtower/watchtower /watchtower
+
+ENTRYPOINT ["/watchtower"]