How can I automatically set a version on a transition?

Question

I'm trying to add a Post Function to a transition automatically set a Version Number on any issue that uses this transition. When I add a Post Function to the transition and use "Update Issue Field", Version is not listed as an option. It's not a dynamic Version number, it's just a static "No Version" value (for incoming support issues that did not require any code changes), so it seems like Script Runner would be overkill. How do I get Version to appear in that Post Function list?

Shylah Weber · Accepted Answer

This accomplished what we were looking for when added as a post-function on the transition.

import com.atlassian.jira.component.ComponentAccessor

import com.atlassian.jira.issue.Issue

import com.atlassian.jira.issue.IssueManager

import com.atlassian.jira.project.Project

import com.atlassian.jira.project.version.Version

import com.atlassian.jira.project.version.VersionManager

import com.atlassian.jira.event.type.EventDispatchOption

import org.apache.log4j.Category

Category log = log;

log.setLevel(org.apache.log4j.Level.DEBUG);

VersionManager versionManager = ComponentAccessor.versionManager

IssueManager issueManager = ComponentAccessor.getIssueManager()

Issue issue  = issue

Project project = issue.getProjectObject()

Version versionFX = versionManager.getVersion(project.getId(), "version")

issue.setFixVersions([versionFX])

issueManager.updateIssue(componentManager.jiraAuthenticationContext.getLoggedInUser(), issue, EventDispatchOption.DO_NOT_DISPATCH, false)