Build compy in Dockerfile

Dockerfile

@@ -1,3 +1,24 @@
+FROM ubuntu:16.04 as compy-builder
+MAINTAINER Barna Csorogi <barnacs@justletit.be>
+
+RUN DEBIAN_FRONTEND=noninteractive apt-get update && \
+    DEBIAN_FRONTEND=noninteractive apt-get upgrade -y && \
+    DEBIAN_FRONTEND=noninteractive apt-get install -y \
+        curl \
+        g++ \
+        git \
+        libjpeg8-dev
+
+RUN mkdir -p /usr/local/ && \
+    curl -O https://storage.googleapis.com/golang/go1.9.linux-amd64.tar.gz && \
+    tar xf go1.9.linux-amd64.tar.gz -C /usr/local
+
+RUN mkdir -p /go/src/github.com/barnacs/compy/
+COPY . /go/src/github.com/barnacs/compy/
+WORKDIR /go/src/github.com/barnacs/compy
+RUN /usr/local/go/bin/go get -d -v ./...
+RUN /usr/local/go/bin/go build -v
+
 FROM ubuntu:16.04
 MAINTAINER Barna Csorogi <barnacs@justletit.be>
 
@@ -12,8 +33,9 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get update && \
 
 WORKDIR /opt/compy
 COPY \
-    compy \
-    docker.sh \
+    --from=compy-builder \
+    /go/src/github.com/barnacs/compy/compy \
+    /go/src/github.com/barnacs/compy/docker.sh \
     /opt/compy/
 
 # TODO: configure HTTP BASIC authentication