Apache Way

JIRA Process

The JIRA handling process outlined below should be followed in absolutely all cases, without exceptions, regardless of the ticket complexity.

New contributors should register account at https://issues.apache.org/jira/secure/Dashboard.jspa and send out email to project's dev list with request for contributors permissions. Committers should handle this request and grant contributor access to new community member.

Getting Started

Easy tickets to get started with Apache Ignite: open tickets with `newbie` label
All other issues: Ignite Jira

Tickets and Versions

Tickets are picked up by community members from a pool of unassigned and unscheduled tickets after discussion on project's dev list. Assigning tickets to a version contributor helps others to understand what will be included in next release.

JIRA issues are grouped by fixVersion field, which is an intended version of the product feature gets merged to. Everyone should make sure that after closing fixVersion is set to a proper version that actually releases the changes made in scope of the ticket.

The following page contains information on upcoming releases (draft) Release Plan.

Ticket Creation

Every JIRA ticket should be sufficiently described.
There should not be any tickets with title only and without description.
If there is a discussion pertaining to the ticket, the ticket should have a link to the dev list.

Working on a ticket

Anyone in the community can start working on any unassigned ticket.
(OPTIONAL) It is recommended to clarify the relevance and correctness of the ticket in the community before doing actual implementation. To do this, you can write an email to the dev.list and wait for answer.
Before beginning working on a ticket, you should assign the ticket to yourself.
Move the ticket to IN PROGRESS state.
If necessary, add comments describing the design decisions or approach you plan to take.

Documenting a ticket

If the changes implemented under the ticket require changes in user documentation, create a related documentation ticket (add "Documentation" to the Component field) and provide a reasonable amount of details in the ticket's description. The information provided in the ticket should be sufficient for any contributor to start working on it. If there is no need to change user documentation, uncheck the Docs Required flag. The Docs Required flag is used to filter out the tickets that require documentation so that our documentation is always up to date.

Review Process and Maintainers

Ignite employs both Review-Then-Commit (RTC) process for most of the components and Commit-Then-Review (CTR) for few ones.
Please consult to Review Checklist to understand how tickets are reviewed and what rules to follow.

Ignite "master" branch should always be release-ready. Please avoid any commits or merges to the "master" branch unless the whole TeamCity CI suite has passed.

Changes to a RTC module should be reviewed at least by one maintainer for that module (which may or may not be the same as the main reviewer) before being merged.

Changes to a CTR module (CTR*) may be merged without waiting for review by a maintainer. However it's advisable to ask a maintainer of a CTR module for review and to wait for some time for his/her feedback.

Component		Maintainers
Ignite Core (the rest of internals not covered below)		Anton Vinogradov Unknown User (agoncharuk)
	PME	Unknown User (jokser)
	Rebalance	Anton Vinogradov Unknown User (jokser)
	Affinity	Unknown User (jokser)
	PDS	Unknown User (agoncharuk)
	Encryption
	Compression
	MVCC	Unknown User (gvvinblade)
	Transactions	Unknown User (ascherbakov)
Marshalling (Binary, Optimized, JDK)
Discovery & Communication SPIs		Unknown User (agoncharuk)
Ignite Compute API
Ignite Services API		Denis Mekhanikov Unknown User (daradurvs)
Ignite SQL & Text Queries & JDBC		Unknown User (jooger)
Ignite Continuous Queries
Machine Learning/Deep Learning (ml, TensorFlow, sub-modules in ml)		Unknown User (zaleslaw)
Build System / Releases		Anton Vinogradov
TeamCity Bot CTR*
Hadoop Accelerator
Spark Integration		Unknown User (nizhikov) Unknown User (zaleslaw)
IGFS
.NET API		Unknown User (ptupitsyn)
C++ API		Unknown User (isapego)
Other thin clients (Python, Node.js, PHP, etc)		Unknown User (isapego)
ODBC		Unknown User (isapego)
JDBC		Unknown User (jooger)
Streamers (JMS, Flume, Kafka, etc.) CTR*		Unknown User (samaitra)
Docker, Mesos, YARN integration
AWS, Google Compute Engine, JClouds integration
OSGi integration
Visor
WebSession & WebSession Filter

Submitting for Review

Attach pull request URL or branch name (see instructions at Workflow)
(OPTIONAL) create an Upsource review: Review With Upsource
Add comment describing what has been implemented.
Move ticket to PATCH AVAILABLE state.

Ask committer to review changes directly.

Check affected files git history to find person most likely able to review changes.

In case it's hard to determine who's able to review by git history use maintainers list presented above.

Add "review request" comment to the Jira Issue starting with a committer username.

for example: "[~avinogradov], Please review my changes."

committer will gain notification and review your changes and/or help to find another committer to do this.

Reviewing a Ticket

Make sure that your patch satisfies Review Checklist rules.
Each comment should be started with [~username] to guarantee proper notification.
committer should add comment like "Changes accepted and ready to be merged." once review successfully finished.
If the committer/contributor has proposals, it is recommended to add a comment in the ticket in addition to PR / CR comments referring proposals added. This helps other committers to identify that fix has something to improve.

Peer Review and LGTM

After a pull request goes through rounds of reviews and revisions, it will become ready for merge. A reviewer signals their approval either by a JIRA/Dev. List comment such as “Looks good to me!” (LGTM).

If the author of the pull request is not a committer, a committer must be the one to approve the change.
If the author of the pull request is a committer, approval from their chosen reviewer is enough. A committer is trusted to choose an appropriate reviewer, even if the reviewer is not a committer.

Once a pull request is approved, any committer can merge it.

Special cases:

Approval from non-committers is encouraged and this review is contribution to the project/community, but such approval has advisory nature.
Ticket can have unlimited number of approvals.
Committers are encouraged to ask other committers for additional review for complex changes.

Exceptions to this rule are rare and made on a case-by-case basis. For example trivial change may be merged by committer without review.

Closing a Ticket

Once ticket has passed all the reviews and has no additional comments, a committer should apply the latest patch to the master branch.
A comment should be added to the ticket stating that the patch has been applied to master.
Move ticket to RESOLVED state.

Review With Upsource

Upsource is an online code review tool. It provides a convenient way to view and discuss changes.

Upsource is optional: it is up to author and reviewer whether to use it or not. Big changes with long discussions are easier to manage in Upsource.

Code author workflow:

Register on http://reviews.ignite.apache.org/
Go to Branches view: http://reviews.ignite.apache.org/ignite/branches
Click on your pull request ("PR XXXX"). Upsource can take up to 1 minute to discover new pull request.
Click "Create branch review"
Rename review to include JIRA key and description (example: "IGNITE-42 Support CacheLoader and CacheWriter")
In JIRA, use More -> Link -> Web Link to link the review page
New changes in the pull request are picked up automatically (may take a minute)

Reviewer workflow:

Follow the Upsource link in JIRA
Select files on the left to view changes
Click on line numbers to leave comments
Leave general comments on the timeline screen
Addressed comments may be marked as "Resolved"
When all issues are resolved (if any), click "Accept" on the top left, and leave a comment in JIRA

Git Process

Apache Ignite community agreed to release new version at least once per quarter. However, duration may be longer or shorter. After development of new functionality is finished, QA cycle starts, then release procedure follows.

Overview

Master should become the development branch for the next release.
Whenever current release goes to QA, new branch should be created from master. This way master can be used to develop functionality of the next release. All release fixes get merged to release branch and then to master.
All individual ticket/features development happen in separate repositories (either local or forks of GitHub mirror - https://github.com/apache/ignite) . Firm rule: ticket/feature branches should never be pushed to repo.
Development branches should be created off of the master branch (or release branch if one exists - in this case changes get merged to release branch and then to master branch). Changes get merged to master branch of the project Git via process described at Workflow.
Git tag should be created for every release.
All CI tests must pass before the merge of ticket branches to the master (or release) branch.

Normally, project repo should contain only master branch, very few branches for ongoing releases and committer's branches ready to be reviewed. Committers and PMC members are in charge to make everyone follow this rule.

Release Process

Instructions on how to build source and binary releases can be found at DEVNOTES.txt. Please see "Ignite Release Instructions" section. On how to make official release please refer to Release Process.

Workflow

There are several ways how you can make contribution

GitHub pull-request
Ticket Branch (only committers)

Create GitHub pull-request

 +------------+             +---------------+            +-----------------+

 |            |   replica   |               |    fork    |                 |

 | Apache Git | ==========> | GitHub Mirror | ---------> | John Doe's Fork |

 |            |             |               |            |                 |

 +------------+             +---------------+            +-----------------+

        ^                            ^                            ^

        |                            |                            |

        |                            +------------------------+   | origin

        |                                  upstream           |   |

        |                                                     |   |

        |                                                +-----------------+

        |    *Apache Git remote handle for committers*   |                 |

        +------------------------------------------------|   Local clone   |

                                                         |                 |

                                                         +-----------------+

Creation

To start:

You need to fork an Apache Ignite mirror on GitHub.
Make a local copy of your Apache Ignite mirror fork. Your remote origin will refer to 'https://github.com/<your_github_uname>/ignite.git'.
You will need to update a local master sometimes (to merge to your development branches sometimes). How to do it:
- Add remote for Apache Ignite mirror (you need to do it once)
```
git remote add upstream https://github.com/apache/ignite.git
```
- Each time when you want to update your local master do the following:
  git pull upstream git checkout master

To make contribution:

Fix / implement JIRA ticket in your fork. Provide Java docs whenever required. If you add a new package make sure that package-info.java file in it is in place with a description. Commit branch to origin (origin = your fork). It's recommended to develop IGNITE-xxx ticket at ignite-xxx branch.
If your contribution is significant (new functionality, deeply reworked existed functionality API) then add an example of usage to 'ignite-example' and add an article to Apache Ignite Documentation.
Create pull request from the new remote branch in the fork to master of Apache Ignite mirror. Please, start a title of the pull request from 'IGNITE-xxx'. An email about the pull request will be send to dev-list and the same JIRA comment will be added to the IGNITE-xxx ticket.
Trigger validation of those test suites that have been affected by your changes on TeamCity:
- Locate a test suite you have to check, press button named "..." that is located on the left of "Run" button. "Run custom build" dialog will appear;
- Go to "Changes" tab and choose "pull/<pull-request-number>/head" in "Build branch" dropdown list;
- Press "Run build" button and monitor tests results.
Once tests are passed, the pull request can be reviewed and merged by a committer. Move a corresponding JIRA ticket to "Patch Available" state by clicking on "Submit Patch" button and let the community know that you're ready for review.

Note: Existing pull request should be updated instead of creation of new one. Creation of more than one pull request for one issue forbidden.

Applying

In additional to contributors configuration, committers need to have one more remote reoi - for working with Apache Git repo. It can be added like this:

git remote add apache https://gitbox.apache.org/repos/asf/ignite.git

To push any branch at Apache repo use

```
git push apache <branch_name>
```

To apply a pull-request it's strongly recommended using ./scripts/apply-pull-request.sh script. Script takes 'pull-request-id' as a parameter and do next:

Checks that you don't have any uncommitted changes.
Checks you are one master branch and master branch is up-to-date.
Updates local master from Apache git repo.
Fetches pull request to a local branch:

git fetch upstream pull/<id>/head:pull-<id>-head

Saves an author and a comment of the last commit at pull-<id>-head.
Merges from the new branch to master:
- ```
git merge --squash pull-<id>-head
```
Ask you about custom comment or using the saved comment.
Commit to local master. The script automatically sign-off a commit and add "Fixes #<id>." suffix to comment (It will close the pull request, see https://help.github.com/articles/closing-issues-via-commit-messages/):
- ```
git commit --author=“<saved_author>" -s -m “<comment> - Fixes #<id>.”
```

Now, you will have one commit at master with all changes from pull-request. Changes can be reviewed again. If you accept all changes and want to push it, do next:

```
 git push apache master
```

Create a Ticket Branch (only committers)

Creation & Applying

Whenever working on bigger features, committers can also create 'ready to be reviewed' branch ignite-XXXX, where XXXX is the number of the JIRA ticket.

TeamCity should be forced to run all tests on created branch before review. Once tests are passed, the branch has be reviewed by module's maintainer.

Created branch name should be attached to a JIRA ticket and the ticket status should be changed on Patch Available.

Branch can be merged to master on successful review by at least one another committer.

Branch should be deleted on branch merged to master or issue cancelled. Committers are in charge of deleting their branches.

Checklist before push

List of points should be checked before push:

Javadoc

Make sure project build log contains no javadoc warnings. Grep build output for "Javadoc Warnings". Covered by Licenses & Javadoc TeamCity task.

Readme

In case a new module is added, make sure it contains README.txt at the module's root.

Documentation & Examples

If the contribution is significant (new feature or significant rework of an existed functionality or API) make sure that an example is added to 'ignite-example' and/or an article is written for Apache Ignite Documentation.

Since readme.io does not automatically copy the changes from the current version to the subsequent version, documentation for any new feature that will be released in the next version should be created within the document for the current version. These new pages should be kept hidden until the next version released.

Licenses

In case new module added, make sure source and binary distributions contains correct license files at modules folders. Covered by Licenses & Javadoc TeamCity task.

Can be checked manually by running command

mvn clean validate -DskipTests=true -P check-licenses

package-info.java

Make sure each package contains package-info.java with proper description.

Project Build

Make sure that command

mvn clean package -DskipTests

finishes without errors.