3.3. Release process

3.3.1. General

This page describes the release process and steps to be followed during development to simplify the release of a final product or a library.

Releasing a product usually consists of publishing the following:

  • Binary or source archives.
  • Documentation, which includes Release Notes, Known Issues and Upgrade Steps.
  • Public announcement. Website news/blog article and newsletter.

Each version sent to a customer should have a unique version number and must be mentioned in the release notes.

Sometimes, special features are required by clients with custom needs and the functionalities are not to be included in the main release series. The versions with dedicated features should be released from their own branches, which are not to be removed. Each release from these branches should have an associated tag. All the related custom bits in the release notes are to be imported into the release notes from the main branch though.

TODO: see what to do with customers using releases from staging… maybe make a production release without a full QA review. Such a release can have a normal version… and if changes are made during the QA review a new patch version is released.

3.3.2. Release Planning

Tickets marked for the ‘next-release’ milestone are technically to be covered for the next release but in most situations these will fall beyond the next release. Tickets that must be in the ‘next-release’ are set with priority ‘High’.

The general timeframe between each release is 30 to 45 days. However, defects are worked on and released as soon as it is feasible by the development team.

3.3.3. Release Review Process

As a means to allow all team members that are involved in coding, testing and supporting the product to keep up with the changes, they must be part of the reviewers of the release branch/PR.

Being part of the release review will help you to acknowledge the changes and to confirm that you have accepted the changes.

The release review request should also include the text used to announce the new release on the website.

3.3.4. Release Manager

During the time of an ‘in-work’ release, a single person is in charge of driving the release, and that person will be the release manager.

Some functions of the release manager are:

  • About 1 week before the release, creating a release milestone and moving all closed tickets from the ‘next-release’ milestone to the new release milestone.
  • Defining the milestone title (PRODUCT_NAME-MAJOR.MINOR.0), description and due date.
  • Creating a dedicated ticket for the release itself, and associating it to the new release milestone.
  • Making sure the ticket dedicated to the release has an owner, and that the owner will do the required steps.
  • Organizing: Some tickets from the next-release milestone which are not yet closed but are soon to be (like needs_merge) can also be moved to the new release milestone.
  • Coordinating story tickets for the milestone.
  • After sending the release branch to RQM, check that the Downloads page is updated and that the trial download links (only direct links) are updated.
  • Check the documentation pages if there are formatting issues, missing images, etc.
  • When creating the release PR add the release news, staging links, direct links to the trial versions, description of what the review and the reviewer names.
  • Check that a tag is created for the release, and that the tag points to the release branch and not the release merge.
  • Checking post-commit BuildBot results for the master branch (about once per week) to make sure no regressions were introduced on the tests executed post-merge.
  • Creating high priority tickets in case the tests are failing on master.
  • When sending branch to production via RQM, edit the protected branch status so that codecov is not required. After release, edit the branch status so that codecov is back to being required.
  • Check that RQM has closed the release PR and associated Trac.
  • After the Downloads page is updated, ensure that the release branch is merged with the master branch via RQM.
  • Update the website with the release news and send to production.
  • Creates and sends the newsletter to the relevant list/s.
  • Ensure that customers that are awaiting for the release. Support will know who the customers are. The ticket can also reference which customer it is.

Release Manager should look into obtaining access to the following:

  • Write access to production website (from infrastructure team) to the news release to the website.
  • Ability to stage a release branch to staging server then to production server.
  • Access to Mailchimp “Pro:Atria” account to send the release newsletter.
  • Access to the Support helpdesk or emails to know which customers should be contacted directly if the release is awaiting upon them.

When the release is out, the Release Manager organizes the team release meeting (times and dates), initiates the call and holds the meeting including a distributed agenda. Release meeting notes are located here Use the version from the previous meeting, in case there were changes in the agenda document such as different numbers.

3.3.5. The Release Branch

A release branch starts like any other branch by creating a ticket in Trac.

The release branch should be created from master (for latest release) or from a tag (for a maintenance release).

Once a release is cut and the release branch is created, it should not be merged with master.

The release branch can cherry-pick certain changes which were added to the release on an expectional basis.

Merging with master might accidentally include changes which should not be released or which might need a new re-release and testing phase. By the time the new re-release is done there might be another new change in master, which if merged will trigger a new circle, and we will never do the release.

With this approach, once the release is cut, the development can continue in master without having to worry about the release.

To integrate with our automated process, the release branch should be named: TICKET_ID-release-MAJOR.MINOR.BUGFIX.

For the latest release, the release branch should only update the release notes and increment the version.

For a maintenance release, besides incrementing the release and creating the release notes, the branch should also cherry pick the fixes or apply dedicated fixes.

The review request for a release branch should include the text used by news articles for our website.

Before requesting the review for this branch, the release should be done on the staging server using the normal RQM command.

These are the extra review steps for a release branch:

  • Release the product on the staging/testing server.
  • Check that story tickets are solved/closed.
  • Check that release notes are valid and with the correct date.
  • Check that version constants were updated
  • Check that known issues are up to date and issues fixed in this release are removed.
  • Check the list of supported operating system (DISTRIBUTABLES in pavement.py) is valid.
  • Check the download page to see that we have files for all the supported OSs.
  • [Linux] From the distributable archives, check that the service can be initialized and started using a Unix init script.
  • [Windows] From the distributable archives, check that the service can be installed and started.

The release itself is done using the automated RQM (Release Queue Manager) process which for now is implemented on top of BuildBot.

Check the repo’s README file for info on how to do the actual release in staging and in production.

These are the extra steps for checking a release in production:

  • Check that the tag was automatically created for the latest release.
  • For maintenance releases, manually create a tag based on the release branch and push the tag.
  • Close the milestone for the current release and re-target all tickets which are not closed yet to next-release.
  • When releasing a <maintenance> release, a new ticket should be created on “next-release” to update release notes.

Future improvements for the automated release process:

  • Add a news article to our website
  • Trigger a website crawler to check broken links for download pages and documentation.

3.3.6. Release Notes

Release notes explain what changed with this version. Period. Release notes are not installation, upgrade or configuration.

Each time a branch fixes a bug, adds a new feature or makes any changes which are visible to end users, a new entry is added inside the release notes file. A release note entry is a summary for one change.

We keep release notes for all versions in a single file so that users can easily read all changes starting from their version up to latest, or up to a specific version.

Release notes are grouped in one of the following categories. The category may be omitted if no changes were added for it. Here are some categories:

* Major changes (only for major releases)
* New features
* Bug fixes with internal bug ID (this is the only section for defect releases)
* Deprecation and Removals
* Documentation changes
* Other changes
* Security related issues (to be highlighted or tagged for easy filtering)

A marker/tag is added at the end of the sentence to point to the ticket ID associated with this change. Having a ticket ID marker is not mandatory for new features.

It can be followed by a list of tags to help users understand / filter the scope of the change. Here are some examples:

* ``[https]`` - for changes affecting only a sub-system.
* ``[aix]`` - for changes affecting only AIX systems.
* ``[windows]`` - for changes affecting only Windows systems.

Remember your audience/user/clients and write for that audience.

Don’t explain every detail of the change. When more details are required use a link to the documentation.

All entries should be complete sentences or phrases, ending with a punctuation mark.

Use present tense as opposed to past tense. The text should state what the change does and not what it did. eg. “Product no longer falls over X.” as opposed to “Product fell over X.”.

Write text in resolution form and describe what impact the change will have on users. What will the users notice?

If a single sentence isn’t clear enough to understand, explaining the background of the change can be helpful, by adding in Previously, X used to do Y or Previously, X used to do Y. Now it does Z.

Don’t add low-level internal details about product logic. Focus on how the change affects / is perceived by the user.

Here are some examples:

  • Support was added for doing / integrating with X.
  • Users can now do X.
  • It is no longer possible to do Y.
  • The text on the ABC form is now Z.
  • Reworded text from X to be gender neutral.
  • Doing X on a session in state Y no longer gives the XYZ error.
  • Fix the XZY error generated when client was doing X on a session in Y state.
  • Previously, users were unable to upload files to a folder if they had write permissions.

3.3.6.1. Sample release notes

Release Notes
=============

This is the list of all changes for PRODUCT NAME releases.


Version 2.1.0, released 24/02/2014
----------------------------------


New features
^^^^^^^^^^^^

* Support was added to transfer files using SCP over SSH.
  Read more... [scp]
* SFTP protocol now supports reading and creating symbolic links on
  Windows. [sftp][windows]


Defect fixes
^^^^^^^^^^^^

* Fixed an internal server error when SSH client requests
  to execute a command, a shell or a pseudo-terminal. [#176][sftp][scp]


Deprecations and removals
^^^^^^^^^^^^^^^^^^^^^^^^^

* It is no longer possible to do X. [#1359][unix]
* Windows XP is no longer supported. [#2345]
* Configuration option X, deprecated since Product version 12.1.2, is now
  removed. [#1366]


Other changes
^^^^^^^^^^^^^

* The HowTo document page of X now has documentation about doing Y. [#2452]



Version 2.0.0, released 20/02/2014
----------------------------------


Major changes
^^^^^^^^^^^^^

* All log handlers were converted to event handlers.
  This allows a unified method for interacting the the audit events
  produced by SFTPPlus.
* All authentication methods are now explicitly defined and ordered.
  You can now choose the order in which different authentication methods
  are used.


New features
^^^^^^^^^^^^

* Support was added to transfer files using SCP over SSH.
  Read more... [scp]


Defect fixes
^^^^^^^^^^^^

* Fixed an internal server error when SSH client requests
  were used to execute a command, a shell, or a pseudo-terminal. [#176][sftp][scp]


Deprecations and removals
^^^^^^^^^^^^^^^^^^^^^^^^^

* It is no longer possible to do X. [#1359][unix]
* Windows XP is no longer supported. [#2345]
* Configuration option X, deprecated since Product version 12.1.2, is now
  removed. [#1366]


Version 1.1.1, released 14/02/2013
----------------------------------


Defect fixes
^^^^^^^^^^^^

* Fixed an internal server error which occurred when an FTP client requested
  an unknown command. [#160][ftp][ftps]

3.3.7. Version Management

Chevah release versions are based on the MAJOR.MINOR.PATCH[.SpecialNN] scheme documented at Semantic Versioning.

A MAJOR version is released to introduce new major features, remove functionalities which have become obsolete, or add features not compatible with previous versions.

MINOR versions are released based on a rolling update development model at intervals varying between 30 to 60 days. The goal is to have functionalities and defect fixes available to customers as soon as possible. Each release has a certain overhead, and the overhead should be minimized by automating the release process.

PATCH versions are released as soon as a defect is fixed, usually one week after it has been initially discovered and reported. Security issues have top priority and a fix is released as soon as possible. PATCH version doesn’t include any new functionality and changes are focused only on fixing the targeted bugs.

SpecialNNN is our non-standard version marker. These versions are not targeted for general availability or for every customer. The special version should be a word or keyword followed by an integer acting as a counter.

In an ideal world a release should be done by preparing a release branch. Then, by issuing a single command, the documentation, download and news pages would be updated. Users would be automatically notified about the new release.

3.3.8. Compatibility Policy

Any release from a MAJOR version release series should be backward and forward compatible with any other release from the same MAJOR series.

That is, users should be able to upgrade or downgrade to any minor release without having to change any external system interaction, API interaction or configuration option.

A MINOR version release might introduce various functionalities which are not available in previous versions. Downgrading to a previous MINOR version will not make the newest functionalities available, but configuration options or other setup specific to newer functionalities should just be ignored in previous MINOR versions, without requiring any other changes.

MAJOR releases are designed to allow major cleanups or redesigns which would break backward compatibility with previous versions.

MAJOR releases should be made at intervals greater than 2 years.

MAJOR releases should support being able to run them in parallel on the same system. This is done to simplify testing, moving the new version in production, or reverting the old version in production in case of problems.

Two MAJOR versions can sometimes not be using the same resource at the same time, e.g. same TCP port, but they should allow fast configuration changes to release a shared resource and to allow use a shared resource.

The upgrading to a new MAJOR version should be designed to require the minimum effort and the process should be automated as much as possible. For example, the straightforward configuration can be automatically migrated.

Some changes might not be automatically migrated and may require user interaction. To simplify the migration process, these changes should be made in MINOR versions as preparation for removals, which will be done in the next MAJOR release. These changes are done by keeping the functionality from the current MAJOR release, but a warning is emitted to inform users about the future changes. User should be pointed to a documentation page describing the changes and providing information on how to prepare the migration.

If the latest MINOR release from a MAJOR release series is operating in production without any removal warnings, then users can upgrade to the next MAJOR release without any other manual migration process.

All removal warnings should have a similar format to simplify filtering and reporting them. The removal message should describe how the value was changed and what steps are required to update/upgrade the configuration to the new functionality.

Here are some steps you can use for testing the compatibility between MAJOR releases. While some functionalities might not be available, the product should still start.

  • Install the new release and use the configuration from the previous major release to start the product. Check that no errors were reported and all services are properly configured and started.
  • Install the previous major release, and use the configuration from the new release to start the product. Make sure that all services are properly configured and no errors are reported.

3.3.9. Releasing a forked library

Sometimes we might need to do small or major changes to an upstream package/library. For example, changes were rejected upstream, or not yet released upstream, or just consist of minor re-packaging changes.

The forked versions should be published only on our private PyPy server and all versions should use the .chevahN suffix.

When forking an upstream project, keep the master/trunk branch as upstream. You can create separate branches dedicated to the Chevah project like master-chevah or release-1.2.3-chevah.

3.3.10. Releasing a library

A library is a collection of software which provides code shared by multiple products. Libraries should always be released using the standard package management system.

Releasing a library consists of the following:

  • creating a distributable in a format used by the package manager.
  • publishing the distributable to the package manager website. In our case most of the time it will be a Python package pushed to our internal PyPi server.

For libraries we aim at releasing a new version with each merge to master. Once you get your branch approved, make sure it has a unique version in setup.py, and then land the branch on master using PQM and release it using:

python setup.py publish

Sometimes, you might want/need to release it before the branch is approved and merged, as you might want to experience how it can be used. This is fine, just make sure that each release has a unique version and it follows the general versioning semantics.

3.3.11. Releasing a product

A product is a stand-alone fully functional application that provides direct functionality to end users.

For now, we will target doing a minor release every 60 days.

Bug fix releases are made on request.

A major release is supported for minimum of 2 years, but our customers are expecting to have support for up to 10 years.

We are now aiming to extending the support / product life cycle to 5 years.

While working on a product, we have the following types of branches:

* master - one master branch with the latest stable development version
* release-branch - ephemeral branches where the version number is updated and release notes finalized.
* task-branch - multiple ephemeral branches where a new feature or fix has a task-branch

Each released version has a dedicated tag. When you need to create a defect release or a maintenance release for a previous version, you will create the release branch based on the desired tag.

The master branch should be kept in good shape so that we can release it at any time. Especially if a security defect is found, we will make a new release as soon as the defect is fixed.

Releases may include fixes for defects observed by customers or new product features requested by customers. In this case it is customary to let a customer know directly that the release is now available. It should be noted to customers that they will still need to take the necessary steps to test the new release in their own environments.