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 Releasing A Parent POM
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 Hervé Boutemy
 Dennis Lundberg
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 2013-12-07
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Releasing A Parent POM

  Releasing a Parent POM is much the same as any other Maven project. The following
  guide walks through most of the steps:

    * {{{./maven-project-release-procedure.html} Maven Project Common Release procedure}}
  
  Note that Parent POMs have particular conventions for managing and deploying the documentation.

* Rationale

  To be able to publish a documentation for the parent POM without affecting released <<<pom.xml>>> and <<<site.xml>>>,
  parent POM projects have a specific structure, with the addition of <<<site-pom.xml>>> and <<<src/site-docs>>>
  to provide <<<mvn -f site-pom.xml site>>> with useful documentation content:

+----+
|-- pom.xml
|-- site-pom.xml
`-- src
    |-- site
    |   `-- site.xml
    `-- site-docs
        |-- apt
        |   `-- index.apt
        `-- site.xml
+----+

  And the <<<index.apt>>> page not only contains instructions about the content of the parent POM, but
  it maintains a history of POM releases links and diffs.

  Each specific step is done to maintain <<<site-pom.xml>>> and <<<index.apt>>> in sync with the release being released.

* Stage the release

  Before staging the release with usual procedure, you need to update <<<site-pom.xml>>> and <<<index.apt>>> to
  take the future release into account:

  [[1]] update <<<site-pom.xml>>> parent POM version to match the version being released,

  [[2]] update <<<src/site-docs/index.apt.vm>>>: add a line in the history of <<<pom.xml>>> for the version being released, referring
  to the future svn release tag and date.
 
  <<Hint>>: in the diff link, the value for the <<<r2>>> parameter is easily found by
  following the previous version's link and copying its revision number.

  []

  Once these modifications are done, you can follow {{{../website/deploy-component-reference-documentation.html}standard component documentation staging steps}},
  taking care to use the <<<site-pom.xml>>> POM, with <<<mvn -f site-pom.xml ...>>> command, each time the parent POM's site is
  generated or published.

  Then the only difference is with commands to stage the site:

+------+
cd target/checkout
mvn -f site-pom.xml site
mvn -f site-pom.xml scm-publish:publish-scm
+------+

* Call the vote

  In the vote, instead of providing links to JIRA, the parent POMs should include a link to the SVN changes since the
  last release (the link previously added to <<<src/site-docs/index.apt>>>):

+-----+
...
Hi,

Changes since the last release:
http://svn.apache.org/viewvc/maven/pom/tags/<TAG>/pom.xml?r1=HEAD&r2=<REVISION-OF-LAST-RELEASE>&diff_format=h

Staging repo:
...
+-----+