BugzillaAutoLanding

Project Description

This project will create and deploy a set of tools that will:

  1. grab patches from a bug in Bugzilla
  2. land patches on try (or other specified branch(es))
  3. poll for the results of automated pushes and depending on the branch specified:
  • report back to the bug the results
  • on success continue to push to another branch (eg: try, then mozilla-inbound)
  • be able to automatically backout a push if failure detected

Goals

  • A set of smaller tools that each have the ability to be part of a larger script that runs "autolanding" to try & other hg.m.o repos that do builds per checkin
  • Tools that can be used in command line via API calls
  • Tools to control the process - lots of toggles to go back to manual sheriffing (Global KillSwitch)
  • Using our build/test resources wisely and not increasing the load so much that try is unusable for developers to work on their patches prior to automated/assisted landings
  • Streamlining as much as possible the try server and trunk landing process without removing the human interaction with the build/test/perf results.

Non-Goals

  • Replacing humans in the landing process
  • Handling performance regressions
  • Providing the best possible UI
  • Going to extreme lengths to support auto-landing patches which do not follow the rules which the tool requires

People

  • Lukas Blakk
  • Marc Jessome

Designing the System

A simple survey on try usage (survey, results) was created and advertised to find out how developers currently use try and what they think about the autolanding workflow. We got 52 responses. This helped catch some things we missed like paying attention to LDAP authentication before pushing something from Bugzilla, and it also provided new observations on try workflow. Many developers state that they would find landing to try via Bugzilla to be 'more work' than what is currently offered with push-to-try (using try syntax). We are taking that into account in our design and are adjusting the goal to be primarily for the purposes of landing to trunk and not just getting try results posted to the bug. That last part will be handled more through try syntax where if a bug is specified, you can post the results to the bug and turn off email notification if desired.

API

Architecture

 

REST Interface

List of request methods, urls, and parameters:

GET /bugs/{bugID} -> get bug patchsets

GET /patchSets/{patchSetID} -> get patchset information

GET /branches/branchName -> get branch information


POST /bugs/{bugID} -> create empty patchset

POST /branches/{branchName} -> create a new branch


PUT /patchSets/{patchSetID}/{patchID} -> add patch to patchset

PUT /branches/{branchName} -> update branch

PUT /branches/{branchName}/threshold -> set branch threshold

PUT /branches/{branchName}/status -> set status enabled/disabled


DELETE /patchSets/{patchSetID} -> delete a patchset (if not processing)

DELETE /branches/{branchName} -> delete branch from db

Object Definitions

PatchSets:

 `id` int(11) NOT NULL AUTO_INCREMENT,
 `bug_id` int(11) DEFAULT NULL,
 `patches` text,
 `revision` text,
 `branch` text,
 `try_run` int(11) DEFAULT NULL,
 `creation_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
 `push_time` timestamp NULL DEFAULT NULL,
 `completion_time` timestamp NULL DEFAULT NULL,

Branches:

 `id` int(11) NOT NULL AUTO_INCREMENT,
 `name` text,
 `repo_url` text,
 `threshold` int(11) DEFAULT NULL,
 `status` text,
 `approval_required` text,
 `push_to_closed` text,

Project Timeline

Component Name Bug(s) Assigned To Description Start Date (est.) Completion Date (est.) On Track Updates
HgPusher bug 657832 Marc Details Monday May 23rd Friday Dec 30th (actual completion) Yes Complete
SchedulerDBPoller bug 430942 Lukas Details Monday May 23rd Friday Dec 30th (actual completion) Yes Complete
BugCommenter bug 659167 Marc Details Monday June 20th Friday July 8th Yes Complete
AutolandDB bug 659166 Marc Details Monday June 20th Friday July 22nd Yes Complete
MessageQueue bug 659166 Marc Details Monday June 13th Friday July 22nd Yes Complete
LDAP Tool bug 666860 Marc Details Monday July 11th Friday July 29th Yes Complete to fill needs of this project

Testing

June 20th - July 22nd

  • Set up on staging masters as per bug 661634 running the automation against the sandbox Bugzilla with autolanding/logging set to staging repos to test the individual components and watch for issues in the message queue and system.

Testing Round 2

Week of Dec 5 - 9

  • Another round of testing the life cycle of a patch attached to sandbox bug using real push to try

What we need to ensure:

  • Not losing every second message to mq
  • No extraneous or unexpected postings to the bug from any modules
  • Push to try should not require full headers on patches
  • Whiteboard syntax either specifying attachment id or not - so [autoland-try] or [autoland-try,1234]
  • Retrying oranges
  • (feature I would like to have) Report back to bug if builds are canceled through self-serve

Week of Dec 12 - 16

Didn't get a full run going on autoland-staging last week, still working out kinks with schedulerdbpoller.

TODO:

  • bug post attempts to non-existent or blocked bugs needs to be handled so that the revision is kicked out of the queue and doesn't get re-posted
  • working on 400 bad requests right now in test_bz_utils

Week of Dec 19 - 23

  • working on thresholds, queue messages, setting up autoland-staging01 to run autoland_queue.py and hgpusher.py
  • filed bug 712360 to address LDAP connection errors
  • have both modules working and speaking to each other but new bugs:
    • hgpusher.py has to be started before autoland_queue.py so that the first time we find an autoland tag the patchset msg succeeds
    • need to not put in a time when a 'bad msg' is returned on attempt to hgpusher
    • message from hgpusher to autoland is broken right now
    • thresholds and the use of 'mozilla-central' as the branch for try are complicated and require review and updating
  • hg clone error doesn't return a message to autoland_queue and doesn't retry
remote: Permission denied (publickey,gssapi-with-mic).
abort: no suitable response from remote hg!
[Clone] error cloning 'ssh://hg.mozilla.org/try' into clean repository:
Command '['hg', 'clone', u'ssh://hg.mozilla.org/try', u'/root/autoland-env/tools/scripts/autoland/build/clean/try']' returned non-zero exit status 255
[HgPusher] Clone error...
  • Why is hgpusher picking up stray autoland.db messages after a blowout error?
(autoland-env)[root@autoland-staging01 autoland]# python hgpusher.py
[RabbitMQ] Established connection to localhost.
[HgPusher] Erroneous message: {u'_meta': {u'queue': u'autoland', 'received_time': '2011-12-21 02:51:24.446963', u'sent_time': u'2011-12-21 02:46:26.146165', u'routing_key': [u'autoland.db'], u'exchange': u'autoland'}, u'payload': {u'action': u'patchset.apply', u'patchsetid': 66, u'type': u'error'}}

Week of Dec 26 - 30

  • bug fixes
  • reworking queues to simplify, use direct topic
  • completed autoland_queue <-> hgpusher communication
  • refactored to be able to do try as its own branch
  • added in a couple more variables to the patchsets (author, retries) and removed to_branch
  • thresholds fixed so that try and mozilla-central aren't conflicting with each other
  • schedulerdbpoller and autoland_queue both push things out if timed out or can't post to bug

Still to do

  • complete end-to-end test running schedulerdbpoller on autoland-staging01
    • first attempt: message of completion from schedulerdbpoller got nabbed by hgpusher
  • hgpusher still has to be started before autoland_queue (why???)
  • more code clean up and review
  • test on actual bugzilla bug (check on attachment name as custom syntax)

Testing Round 3

Weeks of Jan 9 - 13 && Jan 16 - 20

  • review tests and try to get better coverage (80% or higher) on all modules
  • confirm message queues working (Marc: Done)

Deployment

Week of Jan 16th

Go live to a small subset of devs (ehsan plus one or two others), watch for issues using live data from actual pushes/db ===Week of Jan 23 Then go live to all with docs & usage info broadcast widely

TO DO

  • Monitor load & machine resources/wait times
  • Confirm bugs hit from previous attempts are no longer reproducible
  • Write up developer documentation on how to use the current system
  • Write blog posts and promote the new functionality as well as explaining where this is heading (automated landing across release branches)
  • Extend functionality to additional branches (with specific per-branch criteria)

Possible Bugs

These two bugs came up in previous staging runs and should be watched for specifically:

  • Repeated bug posting
  • Queue messages getting lost

API

Write and enable API to give sheriff access to the functionality of this system. Include Kill Switch, ability to override.

Post-Deployment

Outreach

In order to get a lot of eyes (and users) we have a multi-step outreach process to inform developers of this system.

  • Blog posts
  • Tweeting
  • Yammer posts
  • Monday meeting lightning talk
  • Brown Bag
  • File a tracking bug for all bugs filed about any module issues
  • Documentation in wiki.m.o (and possibly in MDN)

Component Descriptions and Implementation Notes

AutolandQueue

A polling script that will pull all bugs from bugzilla with whiteboard tags matching: [autoland-$branch] [autoland-$branch:$patchID:$patchID]

Default behaviour would be to take [autoland-$branch] and grab all non-obsolete, non r- patches and create a patchset db object that is then picked out of the queue to be sent to hgpusher for landing on $branch, results are returned from hgpusher to the AutolandQueue module and analyzed for further actions (like try->mozilla-{central,inbound}). To override or search for regressions the API will support directly inserting a patchset to create a custom autoland run.

HgPusher

Listens for messages that specify a branch push is requested. Accepts a branch, patch id(s) and can clone the branch, apply the patches and report back to the AutolandQueue via message the results of the push (success == revision or FAIL).

  • Input(s): AutolandQueue Messages, command line
  • Output(s): hg.mozilla.org, AutolandQueue Messages, stdout

SchedulerDBPoller

Regularly polls the scheduler DB (cronjob) and checks for completed buildruns for any actively monitored branches. There should be a list to check against for what branches need to be watched. The incomplete runs from the last N units of time are kept by revision in a local cache file to check for completion. When an observed branch has a completed buildrun the SchedulerDBPoller can check two things:

  • if a --post-to-bugzilla flag is present and a bug number is provided following that flag, then the revision will be kept in a local cache and watched until completion (or time out), when done a bug comment will be posted and a message sent out that this revision is complete in case AutolandQueue is interested in that revision
  • Input(s): command line
  • Output(s): AutolandQueue, stdout

Bugzilla Autolanding Extension

The plan is for a BMO Extension that will only be available to people with the correct LDAP permissions.

MessageQueue

This is a util that manages the creation of message queues and routing used by the Autolanding system. It ensures that the right modules receive the right messages.

AutolandDB

Keeps track of the state of an autoland-triggered push from start to finish.

LDAPTool

Checks for hg permission level of submitter Compares bugzilla email to ldap email

Notes

  • Set of tools which automate each step of this work and we can 'on-demand' turn off any of the tools
  • Sheriff needs to be able to turn off the auto-landing altogether
  • No limit in workflow -- sheriff should be able to override the queue to auto-land a priority patch
    • can have oranges, but sheriff could 'force' the landing anyway
  • We need to have stages:
    • (TBD): how to deal with bugzilla
    • HgPusher: deals with the hg stuff (merging patches, grabbing patches from bugs, what happens if any steps fail)
    • SchedulerDB Poller: deals with a way of getting results from try/m-c to make sure we have the data on whether to proceed and/or leave comment in the bug regarding outcomes
    • (fourth, optional/desired/future) how to monitor perf results and get an idea of when it's ok to push or flag on those results
  • Be strict in accepting things from humans
    • Rules for automated landings
    • If they forget a rule, they get a comment - "Step X failed (reason)"
    • For bugs with multiple patches - to land all together, look at non-obsolete patches which have been reviewed in alphabetical order
    • Common for devs to name things "part 1", "part 2"
    • Don't need to be lenient toward human mistakes
    • Need correct descriptions, author information, header of patch -- if it doesn't include a header, try syntax
    • Look at "checkin-needed" box, grab all non-obsolete, and if they have the right message then push all those - if all those steps succeed then you get the try push otherwise fail with comment -- clear "checkin-needed" from the bug
  • Is the bug the right place? It's the public record for the issue, so yes - emailing the assignee takes the information away from the record
  • Specialized tool for patch queues would be nice (not in the scope of this project!)
  • Try syntax presence == try on try_repo but NEVER auto-land on trunk
  • Developers will be encouraged to watch perf results on trunk, since try perf is not really useful information
  • Bot has to watch m-c after it lands something there, results come back to the bug
    • Merge tracking for commits (what was auto-landed and what was not)
    • Merging between two auto-landed pushes
    • We have to watch these to know when all the results are in, and what was successful/not (scheduler db has this information for us to get)
  • Autoland Message Queue - consumes information from BugzillaScraper (pulse?) as event triggerer for HgPusher, BugCommenter

Security

  • Must ensure that the patch is attached by someone with L1 hg access, so that we are auto-landing patches from authors with the same level of security as current push-to-try
    • Why L1? This is about pushing to mozilla-central, so I think we should check for L3 access.
    • L1 to push to try, then reviewer should have L3 for autolanding to trunk

Deployment Coordination with IT

We want to have a production-level system here so what will that require?

  • Set up an autoland-master01 (perhaps move autoland-staging02 to fill this role?) so we can keep autoland-staging01 as our staging environment
  • Nagios alerts on the modules to ensure they are running
  • Emails when there are failures that stop any part of the system

Setting up the staging masters

First run, August 2011

On autoland-staging01 I have done the following:

  • sudo yum install hg
  • checked out my tools repo
  • Installed Python 2.6.7 from source
    • ./configure, make (yum install zlib-devel, readline-devel, bzip2-devel), make install
    • added /usr/local/bin to the PATH in .bashrc to use 2.6 as default Python
  • Set up a virtualenv using these notes
  • in the virtualenv installed:
    • argparse
    • simplejson
    • sqlalchemy
    • mysql-python
  • Also required (but not currently installed):
    • python-ldap for ldap utils
    • pika for rabbitmq communication with python
    • mock for tests

Second run Dec 2011

  • Cloned a read-only of git://github.com/lsblakk/tools.git to /root/autoland-env on autoland-staging01
  • copied in config.ini.prod values from /root/lsblakk-tools/scripts/autoland and made a backup of the config.ini, then did a symlink from config.ini.prod to config.ini
  • pip install urllib3 (to get urllib2) - also had to add import urllib2 to autoland_queue.py
  • rebooted autoland-staging01 to kill any stray processes of mq/rabbit
  • start rabbit server:
su rabbitmq -s /bin/sh -c /usr/lib/rabbitmq/bin/rabbitmq-server
  • JSON errors on request call for bz poller
  • fixed calls to bz_utils __init__ in both autoland_queue and hg_pusher
  • now I can start both and have their queues listening but autoland_queue is reading my bug as not having patches, trying to get it to work with :attachment_id in the tag and there's some patch list/splitting errors
  • yum package of rabbitmq-server was 2.2 and to get rabbitmq-plugins I needed a newer version so did:
yum remove rabbitmq-server
rpm -ivh http://www.rabbitmq.com/releases/rabbitmq-server/v2.7.1/rabbitmq-server-2.7.1-1.noarch.rpm
  • thanks to newer rabbitmq-server, newer erlang needed as well so as per rabbit docs did:
wget -O /etc/yum.repos.d/epel-erlang.repo http://repos.fedorapeople.org/repos/peter/erlang/epel-erlang.repo
yum install erlang


HG Update January 24 2012

  • get latest release from http://pkgs.repoforge.org/mercurial/ (eg mercurial-1.9-1.el5.rf.x86_64.rpm)
  • remove old mercurial version: yum remove mercurial
  • install new version, eg: yum install --nogpgcheck mercurial-1.9-1.e15.rf.x86_64.rpm