Performing a Maven Project Release

This document covers the common release procedures used by the Maven team to perform releases.

Prerequisites

Be sure that:

  • you have a Subversion 1.5+ client installed and on your shell's path. See http://subversion.apache.org/.
  • you have JDK 5 installed and on your shell's path.
  • if you receive an OutOfMemoryError during the build, make sure to have set the environment variable MAVEN_OPTS=-Xmx512m
  • you must use Maven 2.2.1+, as Maven 2.1.0 and 2.2.0 produce incorrect GPG signatures and checksums respectively.
  • follow Apache environment configuration steps outlined at: Publishing Maven Artifacts.

Before you begin

If you started here, you may first want to review one of the following documents that cover the specifics of various types of releases we have in the Maven Project:

Consider updating the parent versions

If the item you are planning to release is not using the most recent version of its parent (see parent POMs index), consider taking this opportunity to update to it.

Make sure that site compilation and publication works

Particularly if you update the parent (but sometimes under other circumstances), the site compilation process may fail, or reveal a conspicuous error, or deploy to the wrong location. It is stressful and time-consuming to discover this *after* you stage a release and then try to follow the procedure to deploy the site for review. So you may find it more pleasant to check out the state of the site before you start.

Stage the Release

  1. Follow the release preparation, staging and closing the repository steps outlined in Staging a Maven release.
  2. Stage the latest documentation as explained in deploying Maven components reference documentation.

Call the vote

Propose a vote on the dev list with the closed issues, the issues left, the staging repository and the staging site. For instance:

To: "Maven Developers List" <dev@maven.apache.org>
Subject: [VOTE] Release Apache Maven XXX Plugin version Y.Z

Hi,

We solved N issues:
http://jira.codehaus.org/secure/ReleaseNote.jspa?projectId=XXX&styleName=Html&version=XXX

There are still a couple of issues left in JIRA:
http://jira.codehaus.org/secure/IssueNavigator.jspa?reset=true&pid=XXX&status=1

Staging repo:
https://repository.apache.org/content/repositories/maven-[YOUR REPOSITORY ID]/
https://repository.apache.org/content/repositories/maven-[YOUR REPOSITORY ID]/[PATH-TO]-source-release.zip

Source release checksum(s):
[NAME-OF]-source-release.zip sha1: [SHA1SUM]

Staging site:
http://maven.apache.org/plugins-archives/maven-XXX-plugin-LATEST/

Guide to testing staged releases:
http://maven.apache.org/guides/development/guide-testing-releases.html

Vote open for 72 hours.

[ ] +1
[ ] +0
[ ] -1

To get the JIRA release notes link, browse to the plugin's JIRA page, select the Road Map link, and use the link to Release Notes that is next to the version being released.

To get the list of issues left in JIRA, browse to the plugin's JIRA page, and from the Preset Filters on the right, use the link for Outstanding issues.

Check the vote results

Copied from Votes on Package Releases.

Votes on whether a package is ready to be released follow a format similar to majority approval
-- except that the decision is officially determined solely by whether at least three
+1 votes were registered. Releases may not be vetoed. Generally the community will table the
vote to release if anyone identifies serious problems, but in most cases the ultimate decision,
once three or more positive votes have been garnered, lies with the individual serving as
release manager. The specifics of the process may vary from project to project, but the
'minimum of three +1 votes' rule is universal.

The list of binding voters is available at http://people.apache.org/committers-by-project.html#maven-pmc (or corresponding group for your project).

Once a vote is successful, post the result to the dev list and cc the PMC. For instance:

To: "Maven Developers List" <dev@maven.apache.org>
CC: "Maven Project Management Committee List" <private@maven.apache.org>
Subject: [RESULT] [VOTE] Release Apache Maven XXX Plugin version Y.Z

Hi,

The vote has passed with the following result:

+1 (binding): <<list of names>>
+1 (non binding): <<list of names>>

I will promote the artifacts to the central repo.

If the vote is unsuccessful, the process will need to be restarted. Be sure to drop your staging repository as described in Dropping a Repo.

Copy the source release to the Apache Distribution Area

The official Apache release is the 'source-release' bundle. All releases must be copied to the official release area. The release area is maintained with svnsubpub. To deliver a release, you add it to the subversion repository for the dist area: add the release, its signature, and corresponding MD5 files. Currently this requires to be in maven-pmc group (see https://issues.apache.org/jira/browse/INFRA-5945).

For example:

wagon/wagon-2.2-source-release.zip
wagon/wagon-2.2-source-release.zip.asc
wagon/wagon-2.2-source-release.zip.md5

You should also run 'svn rm' as needed to clear out older releases. As per the policy, only the latest release on a branch should stay in the main dist areas. So long as the previous release is at least a day old, the automatic archiver will have copied it to the archive.

To check that everything is ok in the dist area, dist-tool-plugin has been written and run once a day to produce "Disttool> Source Release" report.

Promote the release

Once the release is deemed fit for public consumption it can be transfered to a production repository where it will be available to all users.

  1. See Promoting a Repo for details on promotion.
  2. Deploy the current website

    As above, deploy the web site if appropriate and update the project site for the new release. See Publishing versioned component reference documentation. Note that not all projects follow these conventions exactly.

  3. Update the version tracking in JIRA

    In the relevant project, go to Administration, then Versions. Mark the Y.Z version as 'released'. Create version Y.Z+1, if that hasn't already been done. You may also archive any deprecated releases (milestones or alphas) at this time.

  4. Wait for everything to sync
    1. Sync to Maven Central

      The sync into central staging from repository.apache.org occurs every 4 hours. There is a separate hourly schedule that runs which pushes from staging to the other central machines, and then updates the indexes.

    2. Sync to Maven Website

      If the project you are releasing doesn't yet use svnpubsub for site deployment, the deployment of the Maven website will take an hour or so to sync.

  5. Create an announcement.
    1. Using Maven Changes Plugin

      If you are releasing a plugin or a shared component you can let Maven Changes Plugin generate, and eventually even send, the announcement for you. First make sure that you have configured the necessary properties in your committer settings.

      cd target/checkout
      mvn changes:announcement-mail -Papache-release

      If sending the mail should fail, the generated annoucement is available in target/annoucement (see annoucement.vm) and you can use it as a base for sending the mail manually.

      If your SMTP server requires authentication you need to add the command line options for it:

      cd target/checkout
      mvn changes:announcement-mail -Dchanges.username=<SMTP-USERNAME> -Dchanges.password=<SMTP-PASSWORD> -Papache-release
    2. Manually

      Note: You must send this email from your apache email account, e.g. YOUR_APACHE_USERNAME@apache.org otherwise the email to announce@maven.apache.org will bounce.

      From: YOUR_APACHE_USERNAME@apache.org
      To: announce@maven.apache.org, users@maven.apache.org
      Cc: dev@maven.apache.org
      Subject: [ANN] Apache Maven XXX Plugin Y.Z Released
      
      The Apache Maven team is pleased to announce the release of the Apache Maven XXX Plugin, version Y.Z
      
      This plugin (insert short description of the plugin's purpose).
      
      http://maven.apache.org/plugins/maven-XXX-plugin/
      
      You should specify the version in your project's plugin configuration:
      
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-XXX-plugin</artifactId>
        <version>Y.Z</version>
      </plugin>
      
      Release Notes - Maven 2.x XXX Plugin - Version Y.Z
      
      (Copy Here Release Notes in Text Format from JIRA)
      
      Enjoy,
      
      -The Apache Maven team
      
  6. Add the release to the next board report, in the private subversion area.

    This is a PMC activity. If you are not a PMC member then email the Developer's list with a request to update this file for your release.

  7. If releasing the Apache Parent POM, notify release-discuss@apache.org

    Several projects follow this list, and should be made aware of changes to the common parent. This might also be a step to take if other shared resources are released, or if plugin releases are of particular interest to that group.

  8. Celebrate :o)