TeamCity 9.0 Help

Development Environment

Plugin Debugging

You can debug your plugin in a running TeamCity just like a regular Java application debug: start TeamCity server with debug-enabling JVM options and then connect to a remote debug port from the IDE. If you start TeamCity server from outside of your IDE, in IntelliJ IDE you can use "Remote" run configuration, check related external blog post. The JVM options for the server can be set via Configuring TeamCity Server Startup Properties environment variable.

Plugin Reloading

If you make changes to a plugin, you will generally need to shut down the server, update the plugin, and start the server again.

To enable TeamCity development mode, pass the "teamcity.development.mode=true" Configuring TeamCity Server Startup Properties. Using the option you will:

  • Enforce application server to quicker recompile changed .jsp classes

  • Disable JS and CSS resources merging/caching

The following hints can help you eliminate the restart in the certain cases:

  • if you do not change code affecting plugin initialization and change only body of the methods, you can attach to the server process with a debugger and use Java hotswap to reload the changed classes from your IDE without web server restart. Note that the standard hotswap does not allow you to change method signatures.

  • if you make a change in some resource (jsp, js, images) you can copy the resources to webapps/ROOT/plugins/<plugin-name> directory to allow Tomcat to reload them.

  • change in build agent part of plugin will initiate build agents upgrade.

If you replace a deployed plugin .zip file with changed class files while TeamCity server is running, this can lead to NoClassDefFound errors. To avoid this, set "teamcity.development.shadowCopyClasses=true" Configuring TeamCity Server Startup Properties. This will result in:

  • creating ".teamcity_shadow" directory for each plugin .jar file;

  • avoid .jar files update on plugin archive change.

Last modified: 20 April 2023