Merge pull request #3983 from rhcarvalho/docs-and-ci

Document pull request process and improve contribution guide

5 files changed, 236 insertions, 123 deletions

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index a000802e2..a2c582722 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -3,92 +3,103 @@
 Thank you for contributing to OpenShift Ansible. This document explains how the
 repository is organized, and how to submit contributions.
 
-## Introduction
+**Table of Contents**
 
-Before submitting code changes, get familiarized with these documents:
+<!-- TOC depthFrom:2 depthTo:4 withLinks:1 updateOnSave:1 orderedList:0 -->
 
-- [Core Concepts](https://github.com/openshift/openshift-ansible/blob/master/docs/core_concepts_guide.adoc)
-- [Best Practices Guide](https://github.com/openshift/openshift-ansible/blob/master/docs/best_practices_guide.adoc)
-- [Style Guide](https://github.com/openshift/openshift-ansible/blob/master/docs/style_guide.adoc)
+- [Introduction](#introduction)
+- [Submitting contributions](#submitting-contributions)
+- [Running tests and other verification tasks](#running-tests-and-other-verification-tasks)
+	- [Running only specific tasks](#running-only-specific-tasks)
+- [Appendix](#appendix)
+	- [Tricks](#tricks)
+		- [Activating a virtualenv managed by tox](#activating-a-virtualenv-managed-by-tox)
+		- [Limiting the unit tests that are run](#limiting-the-unit-tests-that-are-run)
+		- [Finding unused Python code](#finding-unused-python-code)
 
-## Repository structure
+<!-- /TOC -->
 
-### Ansible
+## Introduction
 
-```
-.
-├── inventory           Contains dynamic inventory scripts, and examples of
-│                       Ansible inventories.
-├── library             Contains Python modules used by the playbooks.
-├── playbooks           Contains Ansible playbooks targeting multiple use cases.
-└── roles               Contains Ansible roles, units of shared behavior among
-                        playbooks.
-```
+Before submitting code changes, get familiarized with these documents:
 
-#### Ansible plugins
+- [Core Concepts](docs/core_concepts_guide.adoc)
+- [Best Practices Guide](docs/best_practices_guide.adoc)
+- [Style Guide](docs/style_guide.adoc)
+- [Repository Structure](docs/repo_structure.md)
 
-These are plugins used in playbooks and roles:
+Please consider opening an issue or discussing on an existing one if you are
+planning to work on something larger, to make sure your time investment is
+something that can be merged to the repository.
 
-```
-.
-├── ansible-profile
-├── callback_plugins
-├── filter_plugins
-└── lookup_plugins
-```
+## Submitting contributions
 
-### Scripts
+1. [Fork](https://help.github.com/articles/fork-a-repo/) this repository and
+   [create a work branch in your fork](https://help.github.com/articles/github-flow/).
+2. Go through the documents mentioned in the [introduction](#introduction).
+3. Make changes and commit. You may want to review your changes and
+   [run tests](#running-tests-and-other-verification-tasks) before pushing your
+   branch.
+4. [Open a Pull Request](https://help.github.com/articles/creating-a-pull-request/).
+   Give it a meaningful title explaining the changes you are proposing, and
+   then add further details in the description.
+
+One of the repository maintainers will then review the PR and trigger tests, and
+possibly start a discussion that goes on until the PR is ready to be merged.
+This process is further explained in the
+[Pull Request process](docs/pull_requests.md) document.
+
+If you get no timely feedback from a project contributor / maintainer, sorry for
+the delay. You can help us speed up triaging, reviewing and eventually merging
+contributions by requesting a review or tagging in a comment
+[someone who has worked on the files](https://help.github.com/articles/tracing-changes-in-a-file/)
+you're proposing changes to.
 
-```
-.
-├── bin                 [DEPRECATED] Contains the `bin/cluster` script, a
-│                       wrapper around the Ansible playbooks that ensures proper
-│                       configuration, and facilitates installing, updating,
-│                       destroying and configuring OpenShift clusters.
-│                       Note: this tool is kept in the repository for legacy
-│                       reasons and will be removed at some point.
-└── utils               Contains the `atomic-openshift-installer` command, an
-                        interactive CLI utility to install OpenShift across a
-                        set of hosts.
-```
+---
 
-### Documentation
+**Note**: during the review process, you may add new commits to address review
+comments or change existing commits. However, before getting your PR merged,
+please [squash commits](https://help.github.com/articles/about-git-rebase/) to a
+minimum set of meaningful commits.
 
-```
-.
-└── docs                Contains documentation for this repository.
-```
+If you've broken your work up into a set of sequential changes and each commit
+pass the tests on their own then that's fine. If you've got commits fixing typos
+or other problems introduced by previous commits in the same PR, then those
+should be squashed before merging.
 
-### Tests
+If you are new to Git, these links might help:
 
-```
-.
-└── test                Contains tests.
-```
+- https://git-scm.com/book/en/v2/Git-Tools-Rewriting-History
+- http://gitready.com/advanced/2009/02/10/squashing-commits-with-rebase.html
 
-## Building openshift-ansible RPMs and container images
+---
 
-See the [build instructions in BUILD.md](BUILD.md).
+## Running tests and other verification tasks
 
-## Running tests
+We use [`tox`](http://readthedocs.org/docs/tox/) to manage virtualenvs where
+tests and other verification tasks are run. We use
+[`pytest`](https://docs.pytest.org/) as our test runner.
 
-We use [tox](http://readthedocs.org/docs/tox/) to manage virtualenvs and run
-tests. Alternatively, tests can be run using
-[detox](https://pypi.python.org/pypi/detox/) which allows for running tests in
-parallel.
+Alternatively to `tox`, one can use
+[`detox`](https://pypi.python.org/pypi/detox/) for running verification tasks in
+parallel. Note that while `detox` may be useful in development to make use of
+multiple cores, it can be buggy at times and produce flakes, thus we do not use
+it in our [CI](docs/continuous_integration.md) jobs.
 
-Note: while `detox` may be useful in development to make use of multiple cores,
-it can be buggy at times and produce flakes, thus we do not use it in our CI.
+```
+pip install tox
+```
 
+To run all tests and verification tasks:
 
 ```
-pip install tox detox
+tox
 ```
 
 ---
 
-Note: before running `tox` or `detox`, ensure that the only virtualenvs within
-the repository root are the ones managed by `tox`, those in a `.tox`
+**Note**: before running `tox` or `detox`, ensure that the only virtualenvs
+within the repository root are the ones managed by `tox`, those in a `.tox`
 subdirectory.
 
 Use this command to list paths that are likely part of a virtualenv not managed
@@ -105,45 +116,45 @@ potentially fail.
 
 ---
 
-List the test environments available:
-
-```
-tox -l
-```
-
-Run all of the tests and linters with:
-
-```
-tox
-```
+### Running only specific tasks
 
-Run all of the tests linters in parallel (may flake):
+The [tox configuration](tox.ini) describes environments based on either Python 2
+or Python 3. Each environment is associated with a command that is executed in
+the context of a virtualenv, with a specific version of Python, installed
+dependencies, environment variables and so on. To list the environments
+available:
 
 ```
-detox
+tox -l
 ```
 
-### Run only unit tests or some specific linter
-
-Run a particular test environment (`flake8` on Python 2.7 in this case):
+To run the command of a particular environment, e.g., `flake8` on Python 2.7:
 
 ```
 tox -e py27-flake8
 ```
 
-Run a particular test environment in a clean virtualenv (`pylint` on Python 3.5
-in this case):
+To run the command of a particular environment in a clean virtualenv, e.g.,
+`pylint` on Python 3.5:
 
 ```
 tox -re py35-pylint
 ```
 
+The `-r` flag recreates existing environments, useful to force dependencies to
+be reinstalled.
+
+## Appendix
+
 ### Tricks
 
+Here are some useful tips that might improve your workflow while working on this repository.
+
 #### Activating a virtualenv managed by tox
 
-If you want to enter a virtualenv created by tox to do additional
-testing/debugging (py27-flake8 env in this case):
+If you want to enter a virtualenv created by tox to do additional debugging, you
+can activate it just like any other virtualenv (py27-flake8 environment in this
+example):
 
 ```
 source .tox/py27-flake8/bin/activate
@@ -182,32 +193,7 @@ $ tox -e py27-unit -- roles/lib_openshift/src/test/unit/test_oc_project.py -k te
 Among other things, this can be used for instance to see the coverage levels of
 individual modules as we work on improving tests.
 
-## Submitting contributions
-
-1. Go through the guides from the [introduction](#Introduction).
-2. Fork this repository, and create a work branch in your fork.
-3. Make changes and commit. You may want to review your changes and run tests
-   before pushing your branch.
-4. Open a Pull Request.
-
-One of the repository maintainers will then review the PR and submit it for
-testing.
-
-The `default` test job is publicly accessible at
-https://ci.openshift.redhat.com/jenkins/job/openshift-ansible/. The other jobs
-are run on a different Jenkins host that is not publicly accessible, however the
-test results are posted to S3 buckets when complete.
-
-The test output of each job is also posted to the Pull Request as comments.
-
-A trend of the time taken by merge jobs is available at
-https://ci.openshift.redhat.com/jenkins/job/merge_pull_request_openshift_ansible/buildTimeTrend.
-
----
-
-## Appendix
-
-### Finding unused Python code
+#### Finding unused Python code
 
 If you are contributing with Python code, you can use the tool
 [`vulture`](https://pypi.python.org/pypi/vulture) to verify that you are not
diff --git a/README.md b/README.md
index 3ec6555e8..42e629484 100644
--- a/README.md
+++ b/README.md
@@ -83,7 +83,10 @@ See [README_CONTAINER_IMAGE.md](README_CONTAINER_IMAGE.md) for information on ho
 
 See the [hooks documentation](HOOKS.md).
 
-
 ## Contributing
 
 See the [contribution guide](CONTRIBUTING.md).
+
+## Building openshift-ansible RPMs and container images
+
+See the [build instructions](BUILD.md).
diff --git a/docs/best_practices_guide.adoc b/docs/best_practices_guide.adoc
index 7f3d85d40..dd849e87d 100644
--- a/docs/best_practices_guide.adoc
+++ b/docs/best_practices_guide.adoc
@@ -11,22 +11,6 @@ All new pull requests created against this repository MUST comply with this guid
 This guide complies with https://www.ietf.org/rfc/rfc2119.txt[RFC2119].
 
 
-== Pull Requests
-
-
-
-[[All-pull-requests-MUST-pass-the-build-bot-before-they-are-merged]]
-[cols="2v,v"]
-|===
-| <<All-pull-requests-MUST-pass-the-build-bot-before-they-are-merged, Rule>>
-| All pull requests MUST pass the build bot *before* they are merged.
-|===
-
-The purpose of this rule is to avoid cases where the build bot will fail pull requests for code modified in a previous pull request.
-
-The tooling is flexible enough that exceptions can be made so that the tool the build bot is running will ignore certain areas or certain checks, but the build bot itself must pass for the pull request to be merged.
-
-
 
 == Python
 
diff --git a/docs/pull_requests.md b/docs/pull_requests.md
new file mode 100644
index 000000000..953563fb2
--- /dev/null
+++ b/docs/pull_requests.md
@@ -0,0 +1,86 @@
+# Pull Request process
+
+Pull Requests in the `openshift-ansible` project follow a
+[Continuous](https://en.wikipedia.org/wiki/Continuous_integration)
+[Integration](https://martinfowler.com/articles/continuousIntegration.html)
+process that is similar to the process observed in other repositories such as
+[`origin`](https://github.com/openshift/origin).
+
+Whenever a
+[Pull Request is opened](../CONTRIBUTING.md#submitting-contributions), some
+automated test jobs must be successfully run before the PR can be merged.
+
+Some of these jobs are automatically triggered, e.g., Travis and Coveralls.
+Other jobs need to be manually triggered by a member of the
+[Team OpenShift Ansible Contributors](https://github.com/orgs/openshift/teams/team-openshift-ansible-contributors).
+
+## Triggering tests
+
+We have two different Jenkins infrastructures, and, while that holds true, there
+are two commands that trigger a different set of test jobs. We are working on
+simplifying the workflow towards a single infrastructure in the future.
+
+- **Test jobs on the older infrastructure**
+
+  Members of the [OpenShift organization](https://github.com/orgs/openshift/people)
+  can trigger the set of test jobs in the older infrastructure by writing a
+  comment with the exact text `aos-ci-test` and nothing else.
+
+  The Jenkins host is not publicly accessible. Test results are posted to S3
+  buckets when complete, and links are available both at the bottom of the Pull
+  Request page and as comments posted by
+  [@openshift-bot](https://github.com/openshift-bot).
+
+- **Test jobs on the newer infrastructure**
+
+  Members of the
+  [Team OpenShift Ansible Contributors](https://github.com/orgs/openshift/teams/team-openshift-ansible-contributors)
+  can trigger the set of test jobs in the newer infrastructure by writing a
+  comment containing `[test]` anywhere in the comment body.
+
+  The [Jenkins host](https://ci.openshift.redhat.com/jenkins/job/test_pull_request_openshift_ansible/)
+  is publicly accessible. Like for the older infrastructure, the result of each
+  job is also posted to the Pull Request as comments and summarized at the
+  bottom of the Pull Request page.
+
+## Triggering merge
+
+After a PR is properly reviewed and a set of
+[required jobs](https://github.com/openshift/aos-cd-jobs/blob/master/sjb/test_status_config.yml)
+reported successfully, it can be tagged for merge by a member of the
+[Team OpenShift Ansible Contributors](https://github.com/orgs/openshift/teams/team-openshift-ansible-contributors)
+by writing a comment containing `[merge]` anywhere in the comment body.
+
+Tagging a Pull Request for merge puts it in an automated merge queue. The
+[@openshift-bot](https://github.com/openshift-bot) monitors the queue and merges
+PRs that pass all of the required tests.
+
+### Manual merges
+
+The normal process described above should be followed: `aos-ci-test` and
+`[test]` / `[merge]`.
+
+In exceptional cases, such as when known problems with the merge queue prevent
+PRs from being merged, a PR may be manually merged if _all_ of these conditions
+are true:
+
+- [ ] Travis job must have passed (as enforced by GitHub)
+- [ ] Must have passed `aos-ci-test` (as enforced by GitHub)
+- [ ] Must have a positive review (as enforced by GitHub)
+- [ ] Must have failed the `[merge]` queue with a reported flake at least twice
+- [ ] Must have [issues labeled kind/test-flake](https://github.com/openshift/origin/issues?q=is%3Aopen+is%3Aissue+label%3Akind%2Ftest-flake) in [Origin](https://github.com/openshift/origin) linked in comments for the failures
+- [ ] Content must not have changed since all of the above conditions have been met (no rebases, no new commits)
+
+This exception is temporary and should be completely removed in the future once
+the merge queue has become more stable.
+
+Only members of the
+[Team OpenShift Ansible Committers](https://github.com/orgs/openshift/teams/team-openshift-ansible-committers)
+can perform manual merges.
+
+## Useful links
+
+- Repository containing Jenkins job definitions: https://github.com/openshift/aos-cd-jobs
+- List of required successful jobs before merge: https://github.com/openshift/aos-cd-jobs/blob/master/sjb/test_status_config.yml
+- Source code of the bot responsible for testing and merging PRs: https://github.com/openshift/test-pull-requests/
+- Trend of the time taken by merge jobs: https://ci.openshift.redhat.com/jenkins/job/merge_pull_request_openshift_ansible/buildTimeTrend
diff --git a/docs/repo_structure.md b/docs/repo_structure.md
new file mode 100644
index 000000000..693837fba
--- /dev/null
+++ b/docs/repo_structure.md
@@ -0,0 +1,54 @@
+# Repository structure
+
+### Ansible
+
+```
+.
+├── inventory           Contains dynamic inventory scripts, and examples of
+│                       Ansible inventories.
+├── library             Contains Python modules used by the playbooks.
+├── playbooks           Contains Ansible playbooks targeting multiple use cases.
+└── roles               Contains Ansible roles, units of shared behavior among
+                        playbooks.
+```
+
+#### Ansible plugins
+
+These are plugins used in playbooks and roles:
+
+```
+.
+├── ansible-profile
+├── callback_plugins
+├── filter_plugins
+└── lookup_plugins
+```
+
+### Scripts
+
+```
+.
+├── bin                 [DEPRECATED] Contains the `bin/cluster` script, a
+│                       wrapper around the Ansible playbooks that ensures proper
+│                       configuration, and facilitates installing, updating,
+│                       destroying and configuring OpenShift clusters.
+│                       Note: this tool is kept in the repository for legacy
+│                       reasons and will be removed at some point.
+└── utils               Contains the `atomic-openshift-installer` command, an
+                        interactive CLI utility to install OpenShift across a
+                        set of hosts.
+```
+
+### Documentation
+
+```
+.
+└── docs                Contains documentation for this repository.
+```
+
+### Tests
+
+```
+.
+└── test                Contains tests.
+```