Specify the URL that points the top level tag directory. For example, job name 'MyJob' with svn URL http://svnserver/trunk/project1 is copied to http://svnserver/tags/last-successful/MyJob/project1 if the tag base URL is specified as http://svnserver/tags/last-successful/${env['JOB_NAME']}.
You can use relative path when you specify multiple locations. For example, the tag base URL above can be represented as ../tags/last-successful/${env['JOB_NAME']}.
The following variables are bound to groovy runtime so that you can embed as a form of GString expression (e.g. ${sys['os.vendor']}) in tag base URL.
sys
System properties
env
Environment variables
repoURL
repoURL, which is the list of svn URL delimited by slash, is bound to groovy runtime so that you can embed a part of svn URL in tag base URL. For example, if you want to tag http://svnserver/tags/last-successful/project1, specify ../tags/last-successful/${repoURL[-1]}. In the case above, repoURL contains the list [http,svnserver,trunk,project1], and negative index allows to access the element from the end of the list.