Add Code Climate CLI example to CI documentation

doc/ci/README.md

@@ -108,6 +108,7 @@ Here is an collection of tutorials and guides on setting up your CI pipeline.
   - [Scala](examples/test-scala-application.md)
   - [Phoenix](examples/test-phoenix-application.md)
   - [Run PHP Composer & NPM scripts then deploy them to a staging server](examples/deployment/composer-npm-deploy.md)
+  - [Analyze code quality with the Code Climate CLI](examples/code_climate.md)
 - **Blog posts**
   - [Automated Debian packaging](https://about.gitlab.com/2016/10/12/automated-debian-package-build-with-gitlab-ci/)
   - [Spring boot application with GitLab CI and Kubernetes](https://about.gitlab.com/2016/12/14/continuous-delivery-of-a-spring-boot-application-with-gitlab-ci-and-kubernetes/)

doc/ci/examples/README.md

@@ -55,6 +55,7 @@ Apart from those, here is an collection of tutorials and guides on setting up yo
 - [Using `dpl` as deployment tool](deployment/README.md)
 - [Repositories with examples for various languages](https://gitlab.com/groups/gitlab-examples)
 - [The .gitlab-ci.yml file for GitLab itself](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/.gitlab-ci.yml)
+- [Analyze code quality with the Code Climate CLI](code_climate.md)
 - **Articles:**
   - [Continuous Deployment with GitLab: how to build and deploy a Debian Package with GitLab CI](https://about.gitlab.com/2016/10/12/automated-debian-package-build-with-gitlab-ci/)

doc/ci/examples/code_climate.md

+# Analyze project code quality with Code Climate CLI
+
+This example shows how to run [Code Climate CLI][cli] on your code by using\
+GitLab CI and Docker.
+
+First, you need GitLab Runner with [docker-in-docker executor](../docker/using_docker_build.md#use-docker-in-docker-executor).
+
+Once you setup the Runner add new job to `.gitlab-ci.yml`:
+
+```yaml
+codeclimate:
+  image: docker:latest
+  variables:
+    DOCKER_DRIVER: overlay
+  services:
+    - docker:dind
+  script:
+    - docker pull codeclimate/codeclimate
+    - docker run --env CODECLIMATE_CODE="$PWD" --volume "$PWD":/code --volume /var/run/docker.sock:/var/run/docker.sock --volume /tmp/cc:/tmp/cc codeclimate/codeclimate init
+    - docker run --env CODECLIMATE_CODE="$PWD" --volume "$PWD":/code --volume /var/run/docker.sock:/var/run/docker.sock --volume /tmp/cc:/tmp/cc codeclimate/codeclimate analyze -f json > codeclimate.json
+  artifacts:
+    paths: [codeclimate.json]
+```
+
+This will create a `codeclimate` job in your CI pipeline and will allow you to
+download and analyze the report artifact in JSON format.
+
+[cli]: https://github.com/codeclimate/codeclimate