Speed-up docker based builds

Enable to:
- Use APT cache
- Use Bundler cache
- Use PhantomJS cache

.gitlab-ci.yml

@@ -9,7 +9,7 @@ variables:
   MYSQL_ALLOW_EMPTY_PASSWORD: "1"
 
 before_script:
-  - ./scripts/prepare_build.sh
+  - source ./scripts/prepare_build.sh
   - ruby -v
   - which ruby
   - gem install bundler --no-ri --no-rdoc

scripts/ci/prepare_build.sh

-#!/bin/bash
-if [ -f /.dockerinit ]; then
-    export FLAGS=(--deployment --path /cache)
-
-    apt-get update -qq
-    apt-get install -y -qq nodejs
-
-    wget -q http://ftp.de.debian.org/debian/pool/main/p/phantomjs/phantomjs_1.9.0-1+b1_amd64.deb
-    dpkg -i phantomjs_1.9.0-1+b1_amd64.deb
-
-    cp config/database.yml.mysql config/database.yml
-    sed -i "s/username:.*/username: root/g" config/database.yml
-    sed -i "s/password:.*/password:/g" config/database.yml
-    sed -i "s/# socket:.*/host: mysql/g" config/database.yml
-else
-    export PATH=$HOME/bin:/usr/local/bin:/usr/bin:/bin
-
-    cp config/database.yml.mysql config/database.yml
-    sed -i "s/username\:.*$/username\: runner/" config/database.yml
-    sed -i "s/password\:.*$/password\: 'password'/" config/database.yml
-    sed -i "s/gitlab_ci_test/gitlab_ci_test_$((RANDOM/5000))/" config/database.yml
-fi

scripts/prepare_build.sh

 #!/bin/bash
+
 if [ -f /.dockerinit ]; then
-    wget -q https://gitlab.com/axil/phantomjs-debian/raw/master/phantomjs_1.9.8-0jessie_amd64.deb
-    dpkg -i phantomjs_1.9.8-0jessie_amd64.deb
+    # Docker runners use `/cache` folder which is persisted every build
+    if [ ! -e /cache/phantomjs_1.9.8-0jessie_amd64.deb ]; then
+        wget -q https://gitlab.com/axil/phantomjs-debian/raw/master/phantomjs_1.9.8-0jessie_amd64.deb
+        mv phantomjs_1.9.8-0jessie_amd64.deb /cache
+    fi
+    dpkg -i /cache/phantomjs_1.9.8-0jessie_amd64.deb
 
     apt-get update -qq
-    apt-get install -y -qq libicu-dev libkrb5-dev cmake nodejs postgresql-client mysql-client
+    apt-get -o dir::cache::archives="/cache/apt" install -y -qq \
+        libicu-dev libkrb5-dev cmake nodejs postgresql-client mysql-client
 
     cp config/database.yml.mysql config/database.yml
     sed -i 's/username:.*/username: root/g' config/database.yml
@@ -13,8 +19,8 @@ if [ -f /.dockerinit ]; then
 
     cp config/resque.yml.example config/resque.yml
     sed -i 's/localhost/redis/g' config/resque.yml
-    FLAGS=(--deployment --path /cache)
-    export FLAGS
+
+    export FLAGS=(--path /cache)
 else
     export PATH=$HOME/bin:/usr/local/bin:/usr/bin:/bin
     cp config/database.yml.mysql config/database.yml