garris#602 - Tagging docker images (garris#617)

* Update Dockerfile and add the build hook to pass the version as
argument (extracted from the package.json file)
* Add the "post_push" hook (to generate the "latest" image)

Author: Baltazardoung

docker/Dockerfile

@@ -1,10 +1,12 @@
 FROM node:8.5.0-alpine
 
+ARG BACKSTOPJS_VERSION
+
 ENV \
 	PHANTOMJS_VERSION=2.1.1 \
 	CASPERJS_VERSION=1.1.4 \
 	SLIMERJS_VERSION=0.10.3 \
-	BACKSTOPJS_VERSION=3.0.36 \
+	BACKSTOPJS_VERSION=$BACKSTOPJS_VERSION \
 	# Workaround to fix phantomjs-prebuilt installation errors
 	# See https://github.com/Medium/phantomjs/issues/707
 	NPM_CONFIG_UNSAFE_PERM=true

docker/hooks/build

@@ -0,0 +1,4 @@
+#!/bin/bash
+BACKSTOPJS_VERSION=$(grep -Po '(?<="version": ")[^"]*' $(dirname "$0")/../../package.json)
+
+docker build --build-arg BACKSTOPJS_VERSION=$BACKSTOPJS_VERSION -t $IMAGE_NAME .

docker/hooks/post_push

@@ -0,0 +1,3 @@
+#!/bin/bash
+docker tag $IMAGE_NAME $DOCKER_REPO:latest
+docker push $DOCKER_REPO:latest