View source for Partnering:Projects:BYOB:PilotBuildQueueDetails

== Overview ==

This is a summary of the moving parts involved in the PHP/MySQL based build
queue in use for the pilot launch of BYOB.

__TOC__
== Repack states ==

The workflow status of a repack is state machine, where each state describes what actions are currently available and to which states it may transition next.

{| border="1" cellpadding="4" width="100%"
! state !! description !! next states
|-
| new || freshly created repack || edited; requested; deleted
|-
| edited || repack with changes || requested; deleted
|-
| requested || user has requested a build and review || cancelled; started; failed; pending
|-
| cancelled || user has cancelled a repack build || edited; requested; deleted
|-
| started || build has started || failed; pending
|-
| failed || build failed for some reason || edited; requested; deleted
|-
| pending || build completed, review pending || cancelled; released; rejected
|-
| rejected || build rejected by editor/admin || edited; requested; deleted
|-
| released || build released to public || reverted
|-
| reverted || public release of build taken down || edited; requested; deleted
|-
| deleted || repack to be deleted from system || --
|}

=== Notes ===

* Repacks are locked as read-only (ie. editing via wizard is disabled) when in these states:
** requested; started; pending; approved
* Repacks get copied on edit as an unreleased version when in these states:
** released

== Build queue ==

The build queue consists of:
* [https://svn.mozilla.org/projects/byob/trunk/modules/messagequeue/config/schema-mysql.sql a MySQL table listing tasks to be performed];
* [https://svn.mozilla.org/projects/byob/trunk/bin/exhaust-queue.sh-dist a shell script] that runs in a crontab or [https://svn.mozilla.org/projects/byob/trunk/bin/org.mozilla.byob.cron.plist-dist as an OS X launchd scheduled task];
** every 5 minutes or so, it sets a lock to prevent concurrent runs and exhausts the queue
* [https://svn.mozilla.org/projects/byob/trunk/modules/messagequeue/controllers/messagequeue.php a PHP controller that processes the queue], using [https://svn.mozilla.org/projects/byob/trunk/modules/messagequeue/models/messagequeue.php a model library] to perform the work.

The web app uses this build queue by:

# [https://svn.mozilla.org/projects/byob/trunk/application/hooks/builds.php Registering DeferredEvent callback handlers with unique IDs] - these do the actual work
# [https://svn.mozilla.org/projects/byob/trunk/application/models/repack.php Firing Events that correspond with registered DeferredEvent handlers] 
#* (search for "function changeState")
# Events result in enqueued tasks, which the queue processor handles with calls to registered DeferredEvent callbacks.

== Build queue tasks in BYOB ==

In reaction to certain state changes, build tasks get enqueued into a PHP/MySQL
based offline work queue that gets exhausted every 5 minutes or so.  The
current build queue tasks are:

=== Perform build ===

* Enqueue triggered by repack transitioning to '''requested''' state.
* Fire up the repack build script
* Move the built repack to private review hosting
* If successful, transition the repack to '''pending''' state.
* If failed, transition the repack to '''failed''' state.

=== Release build ===

* Enqueue triggered by repack transitioning to '''released''' state.
* Move a built repack from private review to public release hosting

=== Delete build ===

* Enqueue triggered by repack transitioning to '''deleted''' state.
* Delete a built repack from both private and public hosting