2.12.6. Upgrading to Buildbot 4.0

Upgrading a Buildbot instance from 3.x to 4.0 may require some work to achieve.

The recommended upgrade procedure is as follows:

Upgrade to the last released BuildBot version in 3.x series.

Remove usage of the deprecated APIs. All usages of deprecated APIs threw a deprecation warning at the point of use. If the code does not emit deprecation warnings, it’s in a good shape in this regard. You may need to run the master on a real workload in order to force all deprecated code paths to be exercised.

Upgrade to the latest Buildbot 4.0.x release.

(Optional) Upgrade to newest Buildbot 4.x. The newest point release will contain bug fixes and functionality improvements.

2.12.6.1. Web frontend

Buildbot 4.0 replaces the AngularJS-based web frontend with a new React-based one. In simple Buildbot installations there is nothing that needs to be done except to install compatible versions of any www plugins that are used. The following plugins are maintained as part of Buildbot and can be upgraded seamlessly by just installing new, compatible version:

buildbot-www (main web frontend)

buildbot-console-view

buildbot-grid-view

buildbot-waterfall-view

Custom plugins

If the Buildbot installation uses plugins that are developed outside Buildbot, these will need to be rewritten to use the new Buildbot plugin APIs that expect the plugin to be written in React. In such case the best approach is to rewrite any custom plugins into React while still using Buildbot 3.x and convert to 4.x once everything is ready.

More specifically, the recommended approach is as follows:

Upgrade to the last released BuildBot version in 3.x series.

Prepare the development environment

Install buildbot-www-react with the same version.

Install any Buildbot plugins that already have a version that is compatible with React. For example buildbot-console-view has a React equivalent buildbot-react-console-view.

Add 'base_react': {} key-value pair to the www plugin dictionary. For example, in the default installation the configuration would look like this: c['www'] = {port: 8080, plugins={'base_react': {}}}.

Other enabled plugins will need their keys in the dictionary changed. For example, the compatibility Buildbot plugins will have the following names:

console_view as react_console_view

grid_view as react_grid_view

waterfall_view as react_waterfall_view

Rewrite any custom Buildbot plugins into React and new Buildbot plugin APIs in the development environment.

Replace the production setup with what was tested in the development environment section above.

Upgrade to Buildbot 4.x series
Buildbot plugins with the word react in the name are temporarily used for migration testing. After a successful migration to Buildbot 4.x, you should replace them with plugins without the word react in the plugin name.
Uninstall migration plugins
pip uninstall buildbot-www-react buildbot-react-console-view buildbot-react-grid-view buildbot-react-waterfall-view  buildbot-react-wsgi-dashboards
Install production plugins
pip install buildbot-www buildbot-console-view buildbot-grid-view buildbot-waterfall-view buildbot-react-wsgi-dashboards
Update the www plugin dictionary

Only update the ones you use in your installation.

Replace:
c['www'] = dict(port=8010,
    plugins=dict('base_react': {}, react_console_view={}, react_grid_view={}, react_waterfall_view={}, react_wsgi_dashboards={}))
With:
c['www'] = dict(port=8010,
    plugins=dict(console_view={}, grid_view={}, waterfall_view={}, wsgi_dashboards={}))

2.12.6.2. GerritChangeSource and GerritEventLogPoller

Events between GerritChangeSource and GerritEventLogPoller are no longer deduplicated. The equivalent is setting GerritChangeSource with both SSH and HTTP APIs. The http_url should be set to baseURL of argument GerritEventLogPoller without the /a suffix included. http_auth should be set to auth argument of GerritEventLogPoller.

2.12.6.3. Build status generators

The subject argument of BuildStatusGenerator and BuildSetStatusGenerator has been removed. The equivalent is setting the subject argument of the message formatter.

2.12.6.4. Message formatters

The wantLogs argument to message formatters has been removed. The equivalent is setting both want_logs and want_logs_content to the previous value of wantLogs.

The wantSteps and wantProperties arguments have been renamed to want_steps and want_properties respectively.

2.12.6.5. GerritStatusPush

The reviewCB, reviewArg, startCB, startArg, summaryCB, summaryArg, builders , wantSteps, wantLogs arguments of GerritStatusPush have been deprecated. The upgrade strategy is as follows:

reviewCB, reviewArg, startCB, startArg: Use BuildStartEndStatusGenerator report generator (generators argument). Depending on reviewCB complexity, use MessageFormatter or MessageFormatterFunctionRaw message formatters. To override default handling of Verified and Reviewed labels, adjust extra information emitted by message formatter. E.g. {"labels": {"Verified": 1}}.

summaryCB, summaryArg: Use BuildSetStatusGenerator or BuildSetCombinedStatusGenerator report generator (generators argument). Depending on summaryCB complexity, use MessageFormatter or MessageFormatterFunctionRaw message formatters. To override default handling of Verified and Reviewed labels, adjust extra information emitted by message formatter. E.g. {"labels": {"Verified": 1}}.

builders - use builders argument of replacement report generator

wantSteps - use want_steps argument of replacement message formatter.

wantLogs - use want_logs argument of replacement message formatter

2.12.6.6. buildbot.util.croniter

buildbot.util.croniter module has been removed. The replacement is croniter package from Pypi.

Migration to croniter involves ensuring that the input times are passed as time-aware datetime objects.

The original buildbot.util.croniter code always assumed the input time is in the current timezone. The croniter package assumes the input time is in UTC timezone.

2.12.6.7. Endpoint attributes

buildbot.data.base.Endpoint no longer provides isRaw and isCollection attributes. The equivalent in Buildbot 4.x is setting the kind attribute to EndpointKind.RAW and EndpointKind.COLLECTION respectively.

2.12.6.8. Changes to BuildStep attributes

BuildBot no longer supports changing BuildStep attributes after a step is created during configuration. Changing attributes of BuildStep instances that are not yet part of any build is most likely an error. This is because such instances are only being used to configure a builder as a source to create real steps from. In this scenario any attribute changes are ignored as far as build configuration is concerned.

For customizing BuildStep after an instance has already been created set_step_arg(name, value) function has been added.