Merge branch 'master' into fix/visibility-level-setting-in-forked-projects

* master: (723 commits)
  Bump Rack Attack to v4.3.1 for security fix
  Remove duplicate entry in the changelog
  Remove extra spaces after branchname
  Fix merge-request-reopen button title
  Add branch and tag operation to tree dropdown
  Use gitlab-shell 2.6.9
  Clarify Windows shell executor artifact upload support
  Fix feature specs: we always show the build status if ci_commit is present
  Do not display project group/name when issue and MR are in same project
  Don't create CI status for refs that doesn't have .gitlab-ci.yml, even if the builds are enabled
  Use gitlab-workhorse 0.5.1
  Fix ci_projects migration by using the value only from latest row [ci skip]
  Revert sidebar position for issue and merge request
  Add info on using private Docker registries in CI [ci skip]
  Upgrade Poltergeist to 1.8.1. #4131
  Fix ux issue with "This issue will be closed automatically" message
  Move MR Builds tab next to Commits
  Api support for requesting starred projects for user
  Fix Rubocop complain.
  Fix merge widget JS for buttons
  ...

Conflicts:
	app/models/project.rb

1 files changed, 114 insertions, 0 deletions

diff --git a/doc/ci/services/postgres.md b/doc/ci/services/postgres.md
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+# Using PostgreSQL
+
+As many applications depend on PostgreSQL as their database, you will
+eventually need it in order for your tests to run. Below you are guided how to
+do this with the Docker and Shell executors of GitLab Runner.
+
+## Use PostgreSQL with the Docker executor
+
+If you are using [GitLab Runner](../runners/README.md) with the Docker executor
+you basically have everything set up already.
+
+First, in your `.gitlab-ci.yml` add:
+
+```yaml
+services:
+  - postgres:latest
+
+variables:
+  POSTGRES_DB: nice_marmot
+  POSTGRES_USER: runner
+  POSTGRES_PASSWORD: ""
+```
+
+And then configure your application to use the database, for example:
+
+```yaml
+Host: postgres
+User: runner
+Password:
+Database: nice_marmot
+```
+
+If you are wondering why we used `postgres` for the `Host`, read more at
+[How is service linked to the build](../docker/using_docker_images.md#how-is-service-linked-to-the-build).
+
+You can also use any other docker image available on [Docker Hub][hub-pg].
+For example, to use PostgreSQL 9.3 the service becomes `postgres:9.3`.
+
+The `postgres` image can accept some environment variables. For more details
+check the documentation on [Docker Hub][hub-pg].
+
+## Use PostgreSQL with the Shell executor
+
+You can also use PostgreSQL on manually configured servers that are using
+GitLab Runner with the Shell executor.
+
+First install the PostgreSQL server:
+
+```bash
+sudo apt-get install -y postgresql postgresql-client libpq-dev
+```
+
+The next step is to create a user, so login to PostgreSQL:
+
+```bash
+sudo -u postgres psql -d template1
+```
+
+Then create a user (in our case `runner`) which will be used by your
+application. Change `$password` in the command below to a real strong password.
+
+*__Note:__ Do not type `template1=#`, this is part of the PostgreSQL prompt.*
+
+```bash
+template1=# CREATE USER runner WITH PASSWORD '$password' CREATEDB;
+```
+
+*__Note:__ Notice that we created the user with the privilege to be able to
+create databases (`CREATEDB`). In the following steps we will create a database 
+explicitly for that user but having that privilege can be useful if in your
+testing framework you have tools that drop and create databases.*
+
+Create the database and grant all privileges on it for the user `runner`:
+
+```bash
+template1=# CREATE DATABASE nice_marmot OWNER runner;
+```
+
+If all went well you can now quit the database session:
+
+```bash
+template1=# \q
+```
+
+Now, try to connect to the newly created database with the user `runner` to
+check that everything is in place.
+
+```bash
+psql -U runner -h localhost -d nice_marmot -W
+```
+
+*__Note:__ We are explicitly telling `psql` to connect to localhost in order
+to use the md5 authentication. If you omit this step you will be denied access.*
+
+Finally, configure your application to use the database, for example:
+
+```yaml
+Host: localhost
+User: runner
+Password: $password
+Database: nice_marmot
+```
+
+## Example project
+
+We have set up an [Example PostgreSQL Project][postgres-example-repo] for your
+convenience that runs on [GitLab.com](https://gitlab.com) using our publicly
+available [shared runners](../runners/README.md).
+
+Want to hack on it? Simply fork it, commit and push  your changes. Within a few
+moments the changes will be picked by a public runner and the build will begin.
+
+[hub-pg]: https://hub.docker.com/_/postgres/
+[postgres-example-repo]: https://gitlab.com/gitlab-examples/postgres