VCS triggers automatically start a new build each time TeamCity detects new changes in the configured VCS roots.
TeamCity periodically (according to the checking for changes interval of a VCS root) polls VCS roots of the build configuration for changes. Newly detected changes appear as Pending Changes of a build configuration.
A new VCS trigger with default settings triggers a build each time new changes are detected.
By default, if you have a build chain (i.e. a number of build configurations interconnected by snapshot dependencies), automatic triggering of builds is performed in one direction only: if a build with snapshot dependencies is triggered, all the builds it depends on are triggered too, but not vice versa. (More about snapshot dependencies).
But it is possible to configure a dependent build to start by enabling the Trigger a build on changes in snapshot dependencies option.
For example, the Test build configuration snapshot-depends on the Compile build configuration. When a Test build is triggered, a Compile build is triggered too. But if Compile is triggered, nothing happens to Test. If you want a Test build to be triggered on changes in Compile, enable Trigger a build on changes in snapshot dependencies in the VCS Trigger options of the Test build configuration. In this setup, no VCS trigger is required for the Compile Build configuration. See also an example at the Build Dependencies page.
If you have fast builds and enough build agents, you can make TeamCity launch a new build for each check-in ensuring that no other changes get into the same build. To do that, select the Trigger a build on each check-in option. Moreover, if you select the Include several check-ins in build if they are from the same committer option, and TeamCity will detect a number of pending changes, it will group them by user and start builds having single user changes only.
This helps in sorting out whose change has broken a build, or caused new test failure.
By specifying the quiet period you can ensure the build is not triggered in the middle of non-atomic check-ins consisting of several VCS check-ins.
Quiet period is a period (in seconds) that TeamCity maintains between the moment the last VCS change is detected and a build is added into the queue. If new VCS change is detected in the Build Configuration within the period, the period starts over from the new change detection time. The build is added into the queue only if there were no new VCS changes detected within the quiet period.
Note that actual quiet period will not be less than maximum checking for changes interval among build configuration VCS roots. Because TeamCity must ensure that changes were collected at least once during the quiet period.
Quiet period can be set to the default value (which can be changed globally at the Administration | Global Settings page), or custom value can be specified.
|Note, that when a build is triggered by a trigger with VCS quiet period set, the build is put into the queue with fixed VCS revisions. This ensures the build will be started with only the specific changes included. Under certain circumstances this build can later become a History Build.|
If no trigger rules specified, a build is triggered upon any detected change displayed for the build configuration. You can affect the changes detected by changing VCS root settings and specifying Checkout Rules.
To limit the changes that trigger the build, use VCS trigger rules. You can add these rules manually in the text area (one per line), or use the Add new rule option to generate them.
Each rule is ether an "include" (starts with "+") or an "exclude" (starts with "-").
The general syntax for a single rule is:
- Ant_like_wildcard - A wildcard to match the changed file path. Only "" and "" patterns are supported, "?" pattern is *not supported. The file paths in the rule can be relative (resulting paths on the agent will be matched) or absolute (started with '/', VCS paths relative to VCS root are matched).
- VCS_username - if specified, limits the rule only to the changes made by a user with corresponding VCS username.
- VCS_root_id - if specified, limits the rule only to the changes from the corresponding VCS root.
- VCS_comment_regexp - if specified, limits the rule only to the changes that contain specified text in VCS comment. Use Java Regular Expression pattern for matching text in a comment (see examples below). The rule matches if the comment text contains matched text portion; to match entire text, include ^ and $ special characters.
For each file in a change the most specific rule is found (the rule matching the longest file path). The build is triggered if there is at least one file with a matching "include" rule or a file with no matching rules.
|When entering rules please note that as soon as you enter any "+" rule, TeamCity will remove the default "include all" setting. To include all the files, use "+:." rule.|
- "-:**.html" excludes all .html files from triggering a build.
- "-:user=techwriter;root=Internal SVN:/misc/doc/*.xml" excludes builds being triggered by .xml files checked in by user "techwriter" to the misc/doc directory of the VCS root named Internal SVN (as defined in the VCS Settings). Note that the path is absolute (starts with "/"), thus the file path is matched from the VCS root.
- "-:lib/**" prevents the build from triggering by updates to the "lib" directory of the build sources (as it appears on the agent). Note that the path is relative, so all files placed into the directory (by processing VCS root checkout rules) will not cause the build to be triggered.
- "-:comment=minor:**" prevents the build from triggering, if the changes check in comment contains word "minor".
- "-:comment=^oops$:**" no triggering if the comment consists of the only word "oops" (according to Java Regular Expression principles ^ and $ in pattern stand for string beginning and ending)
Branch filter setting limits a set of logical branch names according to specified rules. Branch filter has the following format:
Where logical branch name is a part of branch name matched by branch specification (i.e. displayed for a build in TeamCity UI), see Working With Feature Branches. Wildcard character ('*') can also be used.
Only default branch is accepted:
All branches except default are accepted:
Only branches with with feature- prefix are accepted: