Yocto Project Release Process

== Yocto Linux Release Engineering Procedures ==
This document describes release engineering procedures for the Yocto Linux project. 
== Yocto Project Naming Conventions ==
Official/public releases will use the following scheme: M.m.p
* M = major release number
* m = minor release number
* p = minor rev release number (aka "point" or "patch" release)
Major release number changes imply compatibility changes with previous releases. Minor release number changes imply significant changes up to, but not including compatibility changes. Minor rev number changes are for minor issues such as simple bugfixes, security updates, etc. 
Nightly releases will be named using the following scheme: image-name-M.m.p-date-buildnum.extension, where M.m.p is the release number, where date is the datestamp of the build, e.g, 20100715, and buildnum is a build counter, e.g, 1, 2, 3, in case more than one build is generated the same day.
Milestone releases will be named using the following scheme: image-name-M.m.p-date-milestonenum-buildnum.extension, where the field definitions are the same as above with the addition of milestonenum, e.g. M3.
Our first public release was 0.9.0 in October 2010. Our second public release will be the 1.0.0 release in Spring 2011.
=== Yocto Project Releases ===
Yocto Project releases are known by their Major.Minor.patch number. For example:
yocto-1.4.2
The main download directory utilizes this naming convention.
=== Poky Releases ===
Poky is the reference distro the Yocto Project releases with each Yocto Project release. These releases are named releases (danny, dora, dylan, edison, etc.) as well as numbered utilizing Major.minor.patch numbering. 
=== Release Matrix ===
Yocto Project/Poky Releases, while they do not share the same numbering, are released at the same time. This includes point releases. So, for example, the 1.4.1 Yocto Project point release, was used to build the dylan-9.0.1 poky point release.
Yocto Project/Poky Releases
Yocto Project Release	Poky Release Name	Poky Release
3.0.x 	Zeus 	22.0.x
2.7.x 	Warrior 	21.0.x
2.6.x 	thud 	20.0.x
2.5.x 	sumo 	19.0.x
2.4.x 	rocko 	18.0.x
2.3.x 	pyro 	17.0.x
2.2.x 	monty 	16.0.x
2.1.x 	krogoth 	15.0.x
2.0.x 	jethro 	15.0.x
1.8.x 	fido 	13.0.x
1.7.x 	dizzy 	12.0.x
1.6.x 	daisy 	11.0.x
1.5.x 	dora 	10.0.x
1.4.x 	dylan 	9.0.x
1.3.x 	danny 	8.0.x
1.2.x 	denzil 	7.0.x
1.1.x 	edison 	6.0.x
1.0.x 	bernard 	5.0.x
0.9.x 	laverne 	4.0.x
A full listing of releases, code names, Poky and BitBake versions and other related info may be found here:
https://wiki.yoctoproject.org/wiki/Releases
== Types of Releases ==
The day to day testing of the project is now handled through the autobuilder with pre-merge testing of patches.
==== Milestone Releases ====
These releases are performed at the end of a milestone period and are used to measure our progress in delivering new features to Yocto Linux.
To generate a milestone release, we generate a release candidate from master. After each release candidate has cleared QA, the branch is tagged (M.m_M1).
The milestone is copied to the release area preserving links and then cleaned up. We remove rpm/deb directories and then remove .gz files in machines (except for p1022), bz2 files (except for p1022) and then all ext3 files for everything except qemu machines.
==== Point releases/Major Releases ====
These are the final, QA-tested, TSC approved releases of the project.
== Release Components ==
Yocto Linux includes a number of software components to be included in each release. These include:
==== Distro Components ====
* Bootable QEMU images of minimal and sato for the following architectures: qemux86, qemux86-64, qemuarm, qemuarm64, qemumips, qemuppc
** A bootable QEMU image consists of a kernel file, a kernel modules tarball, and root filesystem tarball
* Non-emulated machine targets (e.g, beaglebone-yocto, genericx86, generic86-64, generic-arm64) will include appropriate images (e.g, live images) of minimal and sato.
==== SDK Components ====
* meta-toolchain tarballs for the following host/target combinations: i586/[arm|i586|mips|ppc|x86_64], x86_64/[arm|i586|mips|ppc|x86_64], arm64
* Bootable SDK images for the following architectures: qemux86, qemux86-64, qemuarm, qemuarm64, qemumips, qemuppc
==== Other components ====
* named git archives - a file with each git archived named with the hash of the git commit used the images were built from
* adt repository - A repository of all ipk packages used to build the images (Deprecated as of the 2.0 release. Newer releases now have eSDK instead.)
* RELEASENOTES - a gpg signed file with all bugfixes, added features and git hash info for a release
* *.md5sums - md5sum files of all files within the release
== Release Preparation Notes ==
Need to ensure we:
* Update LAYERSERIES_CORENAMES in meta/conf/layer.conf of OE-Core
* Update LAYERSERIES_COMPAT in meta/conf/layer.conf, meta-skeleton/conf/layer.conf, meta-selftest/conf/layer.conf of OE-Core
* Update LAYERSERIES_COMPAT in conf/layer.conf of meta-gplv2 (not required for yocto-4.1 onward)
* Update LAYERSERIES_COMPAT in conf/layer.conf of meta-mingw
* Add release to scheulers.py in yocto-autobuilder
* Add branch to yocto-autobuilder-helper (usually based on master)
* Copy master branch of yocto-testresults to new release branch
* Copy perf-centos7.yoctoproject.org/master/qemux86 of yocto-buildstats to perf-centos7.yoctoproject.org/<branchname>/qemux86
* Copy perf-ubuntu1604/master/qemux86 of yocto-buildstats to perf-ubuntu1604/<branchname>/qemux86
* Update Poky version (not required for yocto-3.3 onward)
* Update bitbake version
* Update build-appliance SRCREV
== Major/Point Release Procedures ==
=== Release Readiness Review ===
The Release Readiness Review is a sign-off process for official/public Yocto releases. This process reviews feature completeness, status of open defects, testing status, and verifies the status of documentation. From the release readiness review a decision is made on the status of launching an official release.
=== Technical Release Procedures ===
24 hours before the release is made public, the release images would be mirrored to external locations and allow time for the blog and mailing list announcements to be written. The final steps in releasing would be ready to be performed in a matter of seconds:
* Move the release directory from a staging area into the public web server area
* Push the web site update including new release information
* Post the pre-written release announcement on the blog and mailing lists
==== Release Process for the Yocto Project ====
===== Prior to last milestone =====
* Release Engineer gets release name from Richard Purdie and announces it via yocto@yoctoproject.org
* Release Engineer informs Documentation of the new release names so that they have time to modify documentation
===== Last milestone =====
During the last milestone we generally will build from master and then branch when things are at the point where they're mostly stable. We do this to reduce the amount of work required to maintain two branches. Once we're seeing good daily builds and feel confident enough to branch, we will branch the poky, yocto-docs, meta-yocto, yocto-autobuilder-helper repos to a branch named after the name of the release (dora, dylan, laverne, zeus, etc).
===== Prior to release build ===== 
* If the build is a point release, use the appropriate release branch (edison, bernard, etc). If not, create a milestone release branch in the following repositories. The milestone branch follows <Major>.<minor>_M<milestone_number> where Major and minor are Yocto release Major and minor release numbers.
* Set DISTRO and DISTRO_VERSION in meta/conf/poky.conf
* Update handbook references to stable release (introduction.xml, master branch needs this too)
* Update version reference and updated date in handbook (poky-handbook.xml)
* Run the nightly build using the release branch from the autobuilder. This will create images at http://autobuilder.yoctoproject.org/pub/nightly/<datestamp>/.
* If the build is "good", and adequate for delivery to QA, git tag/sign/commit the above repo's release branch HEADs as <Major>.<minor>_M<milestone_number>.rc<release_candidate_number>
* Update MIRRORS to use the autobuilders source dir
===== Release of Build =====
* Run the release script to stage the release. This is not required from Kirkstone onwards. https://git.yoctoproject.org/release-tools/tree/release.py?h=dunfell-ReleaseProcess . This script will do the following...
 - Create the staging directory.
 - Remove the rpm/deb directories. 
 - Delete duplicate files and extraneous blobs, and convert symlinks. 
 - Rename tarballs to reflect current naming conventions. For example. poky-<githash>.tar.bz2 should be renamed to poky-<release_name>-<release_number>.tar.bz2
 - Generate the BSP tarballs
 - Extract the eclipse-plugin archive to http://downloads.yoctoproject.org/releases/eclipse-plugin/<M>.<m> where M.m is the Yocto version
 - Copy the adt-dev repo to the live site (For release lines prior to 2.0.)
 - Create the md5sum table for the release
* Copy the staging directory to the downloads directory (not required for Kirkstone onwards)
* Check the Build log for build issue. Build URL included in build notification email(qa-email).
* Check the testresult and regression report for any issue.
* run https://git.yoctoproject.org/release-tools/tree/testresults.py to combined the manual test result into yocto-testresults. This will create new commit and tag for yocto-testresults. In certain condition this script might break, this can mean something wrong with any artefacts or yocto-testresults* repo. This will also create testreport.txt
* Create release notes, finalize, get approval, and GPG sign notes & git tags. 
* create release notes in .rst and send to docs@lists.yoctoproject.org. (for 4.0 onwards)
* Check the new documentation for the release is available on docs.yoctoproject.org (for 4.0 onward)
* Sync the release out to the mirrors.
* Once sync out is complete, verify that pages work, and download and documentation links work.
* Tag the repos.
* Verify the items on the RELEASE CHECKLIST: https://wiki.yoctoproject.org/wiki/Yocto_Project_Release_Checklist 
* Post release announcement on Blog ( Deprecated ? ) 
* Post release announcement on mailing lists (yocto and yocto-announce)
* Update DISTRO and DISTRO_VERSION in master to be the main release+snapshot