[dist] Reduce build context of docker builds

Every docker image build has a build context that contains files needed
to build the image and a docker file that contains the recipe for the
image build.

By reducing the build context we decrease the overhead of a docker build
quite a bit and thus speed things up (see table below).

In addition clearer seperation of the various docker files we have and
their dependencies, eg. contrib/start_old_tests is only needed by
Dockerfile.old-test-suite.

docker image    before   | after
-------------------------|----------
base:           175.8 MB |  4.096 kB
backend:        175.8 MB |  7.025 MB
frontend-base:  175.8 MB | 18.940 MB
mariadb:        175.8 MB |  2.560 kB
memcached:      175.8 MB |  2.048 kB
old-test-suite: 175.8 MB | 18.940 MB
                         |
build time*:   0m16.364s | 0m1.459s

* running 'time rake docker:maintainer:rebuild' with no source changes
  applied (using cached docker images)

Rakefile

@@ -69,22 +69,22 @@ namespace :docker do
     end
     namespace :rebuild do
       task :base do
-        sh "docker build . -t openbuildservice/base:#{VERSION} -t openbuildservice/base -f Dockerfile.#{VERSION}"
+        sh "docker build docker-files/base/ -t openbuildservice/base:#{VERSION} -t openbuildservice/base -f docker-files/base/Dockerfile.#{VERSION}"
       end
       task :mariadb do
-        sh "docker build . -t openbuildservice/mariadb:#{VERSION} -t openbuildservice/mariadb -f Dockerfile.mariadb"
+        sh "docker build docker-files/mariadb/ -t openbuildservice/mariadb:#{VERSION} -t openbuildservice/mariadb -f docker-files/mariadb/Dockerfile.mariadb"
       end
       task :memcached do
-        sh "docker build . -t openbuildservice/memcached:#{VERSION} -t openbuildservice/memcached -f Dockerfile.memcached"
+        sh "docker build docker-files/memcached/ -t openbuildservice/memcached:#{VERSION} -t openbuildservice/memcached -f docker-files/memcached/Dockerfile.memcached"
       end
       task 'frontend-base' do
-        sh "docker build . -t openbuildservice/frontend-base:#{VERSION} -t openbuildservice/frontend-base -f Dockerfile.frontend-base"
+        sh "docker build src/api/ -t openbuildservice/frontend-base:#{VERSION} -t openbuildservice/frontend-base -f src/api/docker-files/Dockerfile.frontend-base"
       end
       task :backend do
-        sh "docker build . -t openbuildservice/backend:#{VERSION} -t openbuildservice/backend -f Dockerfile.backend"
+        sh "docker build src/backend/ -t openbuildservice/backend:#{VERSION} -t openbuildservice/backend -f src/backend/docker-files/Dockerfile.backend"
       end
       task 'old-test-suite' do
-        sh "docker build . -t openbuildservice/old-test-suite:#{VERSION} -t openbuildservice/old-test-suite -f Dockerfile.old-test-suite"
+        sh "docker build src/api/ -t openbuildservice/old-test-suite:#{VERSION} -t openbuildservice/old-test-suite -f src/api/docker-files/Dockerfile.old-test-suite"
       end
     end
 

docker-compose.yml

@@ -23,7 +23,7 @@ services:
   frontend:
     image: openbuildservice/frontend
     build:
-      context: .
+      context: src/api
     volumes:
       - .:/obs
     ports:

docker-files/api

@@ -0,0 +1 @@
+../src/api/docker-files/

docker-files/backend

@@ -0,0 +1 @@
+../src/backend/docker-files/

Dockerfile.42.3 → docker-files/base/Dockerfile.42.3

@@ -12,7 +12,7 @@ RUN zypper -n install --no-recommends --replacefiles \
   timezone ack glibc-locale sudo aaa_base
 
 # Add our bootstrap script
-ADD contrib/docker-bootstrap.sh /root/bin/docker-bootstrap.sh
+ADD docker-bootstrap.sh /root/bin/docker-bootstrap.sh
 
 # Add our user
 RUN useradd -m frontend

src/api/.dockerignore

@@ -0,0 +1,3 @@
+tmp/*
+log/*
+

Dockerfile.frontend-base → src/api/docker-files/Dockerfile.frontend-base

@@ -5,8 +5,8 @@ RUN /root/bin/docker-bootstrap.sh frontend
 # Install other requirements
 RUN npm install -g jshint
 
-ADD src/api/Gemfile /obs/src/api/Gemfile
-ADD src/api/Gemfile.lock /obs/src/api/Gemfile.lock
+ADD Gemfile /obs/src/api/Gemfile
+ADD Gemfile.lock /obs/src/api/Gemfile.lock
 RUN chown -R frontend /obs/src/api
 
 # Ensure there are ruby, gem and irb commands without ruby suffix

Dockerfile.old-test-suite → src/api/docker-files/Dockerfile.old-test-suite

@@ -4,9 +4,9 @@ RUN /root/bin/docker-bootstrap.sh memcached
 RUN /root/bin/docker-bootstrap.sh backend
 RUN /root/bin/docker-bootstrap.sh frontend
 
-ADD src/api/Gemfile /obs/src/api/Gemfile
-ADD src/api/Gemfile.lock /obs/src/api/Gemfile.lock
-ADD contrib/start_old_tests /obs/contrib/start_old_tests
+ADD Gemfile /obs/src/api/Gemfile
+ADD Gemfile.lock /obs/src/api/Gemfile.lock
+ADD docker-files/start_old_tests /obs/contrib/start_old_tests
 RUN chown -R frontend:users /obs/
 
 # Set up some convenience ruby binaries...

src/backend/.dockerignore

@@ -0,0 +1,2 @@
+src/backend/t/*
+

Dockerfile.backend → src/backend/docker-files/Dockerfile.backend

@@ -3,7 +3,7 @@ FROM openbuildservice/base
 RUN /root/bin/docker-bootstrap.sh backend
 
 # Add our sign configuration
-ADD dist/obs-signd-conf.tar.bz2 /
+ADD docker-files/obs-signd-conf.tar.bz2 /
 
 # Run our command
 WORKDIR /obs