From b70e868a2df94133c6a2210b57e0c61beb74525e Mon Sep 17 00:00:00 2001
From: Jan Grewe <jan@faked.org>
Date: Sun, 25 Nov 2018 17:51:57 +0100
Subject: [PATCH] use multi-stage build for Docker images, decreasing the size
 by >80%

---
 Dockerfile.magneticod | 12 ++++++------
 Dockerfile.magneticow |  7 +++++--
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/Dockerfile.magneticod b/Dockerfile.magneticod
index 6d60a65..4c3361a 100644
--- a/Dockerfile.magneticod
+++ b/Dockerfile.magneticod
@@ -2,7 +2,7 @@
 
 # Start from a Debian image with the latest version of Go installed
 # and a workspace (GOPATH) configured at /go.
-FROM golang:1.10
+FROM golang:1.10 AS build
 
 # Copy the local package files to the container's workspace.
 ADD ./Gopkg.toml      /go/src/github.com/boramalper/magnetico/
@@ -20,9 +20,9 @@ RUN     make test-persistence
 RUN     make test-magneticod
 RUN     make magneticod
 
-# Run the outyet command by default when the container starts.
-ENTRYPOINT ["/go/bin/magneticod"]
-CMD []
+FROM alpine:latest
+WORKDIR /
+COPY --from=build /go/bin/magneticod /magneticod
 
-# Document that the service listens on port 8080.
-EXPOSE 8080
+# Run the outyet command by default when the container starts.
+ENTRYPOINT ["/magneticod"]
diff --git a/Dockerfile.magneticow b/Dockerfile.magneticow
index dbea944..6f0ce23 100644
--- a/Dockerfile.magneticow
+++ b/Dockerfile.magneticow
@@ -20,9 +20,12 @@ RUN     make test-persistence
 RUN     make test-magneticow
 RUN     make magneticow
 
+FROM alpine:latest
+WORKDIR /
+COPY --from=build /go/bin/magneticow /magneticow
+
 # Run the outyet command by default when the container starts.
-ENTRYPOINT ["/go/bin/magneticow"]
-CMD []
+ENTRYPOINT ["/magneticow"]
 
 # Document that the service listens on port 8080.
 EXPOSE 8080