Gitflow Cheat Sheet

Intro

PHP-RBAC has adopted the Gitflow branching system and workflow.

The following is a crash course/cheat-sheet/reference for the Gitflow branching model.

Because Vincent Driessen did such a great job introducing Gitflow in his article (Official Gitflow proposal), we've decided to stand on the shoulder of giants and either paraphrased snippets of his article, or we've copied/pasted from his article where it seemed appropriate.

Core Concepts

Main Branches

At the core, the development model is greatly inspired by existing models out there.

The central repo holds two main branches with an infinite lifetime:

master (cut on merge from 'release-*'),
develop (cut from 'master')

Supporting Branches

Next to the main branches 'master' and 'develop', this development model uses a variety of supporting branches to:

Aid parallel development between team members
Ease tracking of features
Prepare for production releases
Assist in quickly fixing live production problems

Unlike the main branches, these supporting branches always have a limited life time, since they will be removed eventually.

The different types of supporting branches we may use are:

Feature branches (cut from 'develop', merge back into 'develop')
Release branches (cut from 'develop', merge back into 'develop' and 'master')
Hotfix branches (may cut from 'master' or 'release-*', merge back into 'develop' and 'master' or 'release-*')

Main Branches Explained

master

The 'master' branch contains most current stable release.
The 'master' branch always reflects a production-ready state
The 'master' branch shouldn't be touched until a new release is merged from 'develop'.
This branch has an infinite lifetime.

develop

The 'develop' branch is originally cut from 'master'.
The 'develop' branch always reflects a state with the latest delivered development changes for the next release.
Some would call this the “integration branch”.
The 'develop' branch is where any automatic nightly builds are built from.
All topics branches will be merged into the 'develop' branch in preparation for the next release.
When the source code in the 'develop' branch reaches a stable point and is ready to be released, all of the changes should be merged back into master somehow and then tagged with a release number.
Every time changes are merged back into 'master' from 'develop', this is a new production release by definition.

Supporting Branches Explained

Feature Branches

Feature Branch Properties

May branch off from: develop
Must merge back into: develop
Branch naming convention: anything except 'master', 'develop', 'release-*', or 'hotfix-*'

Feature Branch Information

Feature branches (or sometimes called topic branches) are used to develop new features for the upcoming or a distant future release.
When starting development of a feature, the target release in which this feature will be incorporated may well be unknown at that point.
The essence of a feature branch is that it exists as long as the feature is in development, but will eventually be merged back into 'develop' (to definitely add the new feature to the upcoming release) or discarded (in case of a disappointing experiment).
Feature branches typically exist in developer repos only, not in 'origin'.

Creating a Feature Branch

When starting work on a new feature, branch off from the develop branch:
```
  $ git checkout -b myfeature develop
```

Incorporating a finished feature on develop

Finished features may be merged into the develop branch definitely add them to the upcoming release:

  $ git checkout develop
  Switched to branch 'develop'
  $ git merge --no-ff myfeature
  Updating ea1b82a..05e9557
  (Summary of changes)
  $ git branch -d myfeature
  Deleted branch myfeature (was 05e9557).
  $ git push origin develop

The --no-ff flag causes the merge to always create a new commit object, even if the merge could be performed with a fast-forward. This avoids losing information about the historical existence of a feature branch and groups together all commits that together added the feature.

Release Branches

Release Branch Properties

May branch off from: develop
Must merge back into: develop and master
Branch naming convention: release-*

Release Branch Information

Release branches support preparation of a new production release.
They allow for last-minute dotting of i’s and crossing t’s.
Furthermore, they allow for minor bug fixes and preparing meta-data for a release (version number, build dates, etc.).
By doing all of this work on a release branch, the 'develop' branch is cleared to receive features for the next big release.
The key moment to branch off a new release branch from 'develop' is when 'develop' (almost) reflects the desired state of the new release.
At least all features that are targeted for the release-to-be-built must be merged in to 'develop' at this point in time.
All features targeted at future releases may not (be merged in to 'develop') — they must wait until after the release branch is branched off.
It is exactly at the start of a release branch that the upcoming release gets assigned a version number—not any earlier. Up until that moment, the develop branch reflected changes for the “next release”, but it is unclear whether that “next release” will eventually become 0.3 or 1.0, until the release branch is started. That decision is made on the start of the release branch and is carried out by the project’s rules on version number bumping.

Creating a Release Branch

Release branches are created from the 'develop' branch.

For example, say version 1.1.5 is the current production release and we have a big release coming up. The state of 'develop' is ready for the “next release” and we have decided that this will become version 1.2 (rather than 1.1.6 or 2.0).

So we branch off and give the release branch a name reflecting the new version number:

  $ git checkout -b release-1.2 develop
  Switched to a new branch "release-1.2"
  $ ./bump-version.sh 1.2
  Files modified successfully, version bumped to 1.2.
  $ git commit -a -m "Bumped version number to 1.2"
  [release-1.2 74d9424] Bumped version number to 1.2
  1 files changed, 1 insertions(+), 1 deletions(-)

After creating a new branch and switching to it, we bump the version number.

Here, bump-version.sh is a fictional shell script that changes some files in the working copy to reflect the new version. (This can of course be a manual change—the point being that some files change.)
Then, the bumped version number is committed.
This new branch may exist there for a while, until the release may be rolled out definitely.
During that time, bug fixes may be applied in this branch (rather than on the 'develop' branch).
Adding large new features here is strictly prohibited.

They must be merged into 'develop', and therefore, wait for the next big release.

Finishing a Release Branch

When the state of the release branch is ready to become a real release, some actions need to be carried out.
- First, the release branch is merged into master (since every commit on master is a new release by definition, remember).
- Next, that commit on master must be tagged for easy future reference to this historical version.
- Finally, the changes made on the release branch need to be merged back into develop, so that future releases also contain these bug fixes.
- The first two steps in Git:
```
    $ git checkout master
    Switched to branch 'master'
    $ git merge --no-ff release-1.2
    Merge made by recursive.
    (Summary of changes)
    $ git tag -a 1.2
```
- The release is now done, and tagged for future reference.
```
**Note:** You might as well want to use the **-s** or **-u <key>** flags to sign your tag cryptographically.
```
To keep the changes made in the release branch, we need to merge those back into develop, though. In Git:
```
  $ git checkout develop
  Switched to branch 'develop'
  $ git merge --no-ff release-1.2
  Merge made by recursive.
  (Summary of changes)
```
- This step may well lead to a merge conflict (probably even, since we have changed the version number). If so, fix it and commit.
Now we are really done and the release branch may be removed, since we don’t need it anymore:
```
  $ git branch -d release-1.2
  Deleted branch release-1.2 (was ff452fe).
```

Hotfix Branches

Hotfix Branch Properties

May branch off from: master
Must merge back into: develop and master
Branch naming convention: hotfix-*

Hotfix Branch Information

Hotfix branches are very much like release branches in that they are also meant to prepare for a new production release, albeit unplanned.
They arise from the necessity to act immediately upon an undesired state of a live production version.
When a critical bug in a production version must be resolved immediately, a hotfix branch may be branched off from the corresponding tag on the 'master' branch that marks the production version.
The essence is that work of team members (on the 'develop' branch) can continue, while another person is preparing a quick production fix.

Creating a Hotfix Branch

Hotfix branches are created from the master branch.
For example, say version 1.2 is the current production release running live and causing troubles due to a severe bug. But changes on develop are yet unstable.

We may then branch off a hotfix branch and start fixing the problem:

  $ git checkout -b hotfix-1.2.1 master
  Switched to a new branch "hotfix-1.2.1"
  $ ./bump-version.sh 1.2.1
  Files modified successfully, version bumped to 1.2.1.
  $ git commit -a -m "Bumped version number to 1.2.1"
  [hotfix-1.2.1 41e61bb] Bumped version number to 1.2.1
  1 files changed, 1 insertions(+), 1 deletions(-)

Don’t forget to bump the version number after branching off!

Then, fix the bug and commit the fix in one or more separate commits.

  $ git commit -m "Fixed severe production problem"
  [hotfix-1.2.1 abbe5d6] Fixed severe production problem
  5 files changed, 32 insertions(+), 17 deletions(-)

Finishing a Hotfix Branch

When finished, the bugfix needs to be merged back into 'master', but also needs to be merged back into 'develop', in order to safeguard that the bugfix is included in the next release as well.

This is completely similar to how release branches are finished.

First, update master and tag the release:

  $ git checkout master
  Switched to branch 'master'
  $ git merge --no-ff hotfix-1.2.1
  Merge made by recursive.
  (Summary of changes)
  $ git tag -a 1.2.1

Note: You might as well want to use the -s or -u flags to sign your tag cryptographically.

Next, include the bugfix in develop, too:
```
  $ git checkout develop
  Switched to branch 'develop'
  $ git merge --no-ff hotfix-1.2.1
  Merge made by recursive.
  (Summary of changes)
```
Note: The one exception to the rule here is that, when a release branch currently exists, the hotfix changes need to be merged into that release branch, instead of develop.
Back-merging the bugfix into the release branch will eventually result in the bugfix being merged into 'develop' too, when the release branch is finished.

(If work in 'develop' immediately requires this bugfix and cannot wait for the release branch to be finished, you may safely merge the bugfix into 'develop' now as well.)

Finally, remove the temporary branch:

  $ git branch -d hotfix-1.2.1
  Deleted branch hotfix-1.2.1 (was abbe5d6).

Historical Branches

The PhpRbac/Classic Branch

Contains the PHP-RBAC v1.0 code base

Provide feedback

Saved searches

Use saved searches to filter your results more quickly