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Revision 1 as of 2010-02-12 16:05:39
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Editor: bjornt
Comment:
Revision 22 as of 2010-07-22 14:51:59
Size: 2838
Editor: mars
Comment:
Deletions are marked like this. Additions are marked like this.
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This is a proposal of how a developer branch flows through the different production branches we have, after the developer branch is ready for landing. This is a proposal of how a developer branch flows through the different
production branches we have, after the developer branch is ready for
landing.
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To summarize, branches that contain db changes always get landed to the `db`
branch. Other changes get landed to the `edge` branch, although branches that are part of a larger features (consisting of multiple branches) get landed to edge through an integration branch for that feature.
= Merge Workflow Draft =
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The landed revision stays in the `edge` branch until it has been marked as
being QAed. When the revision is marked as good, it automatically gets merged
into the `production` branch, which is rolled out to `launchpad.net` daily.
Bugfixes land on the `stable` branch and are rolled out daily to a
"QA testing" server for QA. Revisions that have been marked QA-OK
are copied to a `production` branch and then rolled out daily to
production and edge.
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{{attachment:merge-workflow.png}} Branches that contain db changes land on the `db-stable` branch, and
are QA'd on staging. The `db-stable` branch is updated daily with
changes from `stable`, as happens today. DB changes are rolled out
monthly, also as it happens today.

{{attachment:mergeworkflow.png}}

''(Old image: [[attachment:merge-workflow-draft-2.jpeg]])''
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A revision gets merged from `edge` to `production` only after it has been
marked as good in the QA step. This helps ensure that we don't rollout feature
to `launchpad.net` that haven't been QAed.
A revision gets merged from `stable` to `production` only after it has
been marked as good in the QA step. This helps ensure that we don't
rollout feature to `launchpad.net` that haven't been QAed.
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XXX: How the QA step works regarding to marking the revision as good/bad is still
undefined.
In addition to this, a revision only gets merged from `stable` to
`production` if all the previous revisions have been marked as good as
well. This is because bzr doesn't support cherry picking, and we want to
keep track of which revisions have been merged.

How the QA step works regarding to marking the revision as good/bad is described on [[QAProcessContinuousRollouts]].

=== What if I don't do my QA, or my QA is bad? ===

If someone does not do their QA, or their branch fails QA, then they will
block production/edge rollouts until that revision is reverted.
Rollouts from `stable` to the QA server will still continue, so other
developers can still continue their QA as normal.

We assume a two day grace period for QA - if on the third day a branch has
not been QA'd, then anyone on the team may revert the offending revision.
 We must focus on making these reversions as easy and painless as possible.
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== Feature branches == === What if I have to do QA that takes a few days? ===
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Features that will involve multiple branches should have an integration branch
for that feature. Instead of landing branches related to the feature to `edge`,
they land their branches to the integration branch. New revisions in the
integration branch will automatically be merge into the `edge` branch.

The reason for having an integration branch branch is to keep track of all the
revisions that belong to the feature, so that when the feature has been marked
as good in the QA process, the whole feature can be rolled out at once. Parts
of the feature can still be rolled out by QAing specific revisions.

XXX: How to register new feature branches, and how to merge to them, is still
undefined. Maybe a better way would be to use revision properties to tag
revisions as being part of a bigger feature, or use bug links?

=== Resolving conflicts ===

If there's a conflict when automatically merging the feature branch into the `edge` branch, someone has to manually merge the feature branch into `edge` and resolve the conflicts.
If a feature requires more than one day of QA, then developers have the option
to do the QA on the `staging.launchpad.net` server, to requisition an additional server,
(dogfood), or ask for permission to block the daily QA rollouts for more than
two or three days.
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== Bug fixes == == The Rollout ==
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Bug fixes for features that already exposed on `launchpad.net` can go directly
to the `edge` branch. After the revision has been QAed, it gets merged into the
`production` branch.
Rollouts of database changes still happen as before.
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== Continuous rollouts to `launchpad.net` == == Large Features That Span Branches ==
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The `production` branch gets rolled out to the web app servers daily, to expose
our users to bug fixes not too long after the fix has been verified to work on
`edge.launchpad.net`.
If you have a feature that will span multiple branches, then it is expected
that the developers will create a feature switch to optionally enable that
part of the code, or that early branches that have no user-facing changes
will be marked as `qa-untestable`.
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We only do this for the web app servers, since we can update them without any
downtime.
== Emergency Fixes/Cherry Picks ==
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XXX: If we're not ready for this, things could get merged into the `db` branch after being QAed, waiting to get rolled out with the next release.


== What about `staging.launchpad.net` ==

Staging takes the `edge` branch and merges in the `db` branch.
The cherry-pick procedure remains the same as it does currently - you must
land the change on both the `production` branch and later on the `stable`
branch.

This is a proposal of how a developer branch flows through the different production branches we have, after the developer branch is ready for landing.

Merge Workflow Draft

Bugfixes land on the stable branch and are rolled out daily to a "QA testing" server for QA. Revisions that have been marked QA-OK are copied to a production branch and then rolled out daily to production and edge.

Branches that contain db changes land on the db-stable branch, and are QA'd on staging. The db-stable branch is updated daily with changes from stable, as happens today. DB changes are rolled out monthly, also as it happens today.

mergeworkflow.png

(Old image: merge-workflow-draft-2.jpeg)

The QA step

A revision gets merged from stable to production only after it has been marked as good in the QA step. This helps ensure that we don't rollout feature to launchpad.net that haven't been QAed.

In addition to this, a revision only gets merged from stable to production if all the previous revisions have been marked as good as well. This is because bzr doesn't support cherry picking, and we want to keep track of which revisions have been merged.

How the QA step works regarding to marking the revision as good/bad is described on QAProcessContinuousRollouts.

What if I don't do my QA, or my QA is bad?

If someone does not do their QA, or their branch fails QA, then they will block production/edge rollouts until that revision is reverted. Rollouts from stable to the QA server will still continue, so other developers can still continue their QA as normal.

We assume a two day grace period for QA - if on the third day a branch has not been QA'd, then anyone on the team may revert the offending revision.

  • We must focus on making these reversions as easy and painless as possible.

What if I have to do QA that takes a few days?

If a feature requires more than one day of QA, then developers have the option to do the QA on the staging.launchpad.net server, to requisition an additional server, (dogfood), or ask for permission to block the daily QA rollouts for more than two or three days.

The Rollout

Rollouts of database changes still happen as before.

Large Features That Span Branches

If you have a feature that will span multiple branches, then it is expected that the developers will create a feature switch to optionally enable that part of the code, or that early branches that have no user-facing changes will be marked as qa-untestable.

Emergency Fixes/Cherry Picks

The cherry-pick procedure remains the same as it does currently - you must land the change on both the production branch and later on the stable branch.

MergeWorkflow (last edited 2010-11-08 22:01:23 by lifeless)