### Background
This extension was developed in 2008 by Brion Vibber and Aaron Schulz back when our code was still hosted using Subversion (SVN). While Subversion did not accomodate a workflow to review code before committing, this MediaWiki extension was developed to make it easy to view, annotate and review code changes after committing.
This feature was used for all Wikimedia development until 2012, when the migration to Git and Gerrit started. The transition was completed by 1 August 2013. More about this at <https://www.mediawiki.org/wiki/Git/Conversion>.
The feature can be seen at <https://www.mediawiki.org/wiki/Special:Code/MediaWiki>.
**Documentation**: <https://www.mediawiki.org/wiki/Extension:CodeReview>.
**Repository**: <https://gerrit.wikimedia.org/g/mediawiki/extensions/CodeReview/> ([GitHub mirror](https://github.com/wikimedia/mediawiki-extensions-CodeReview))
**Maintainer(s)** ([per mw.org](https://www.mediawiki.org/wiki/Developers/Maintainers)): Jack Phoenix, Chad Horohoe, Sam Reed.
**First deployed to Wikimedia production**: In 2009.}
### Problem statement
Since Jan 2013, the "review" feature of this extension have not been in use at Wikimedia. However, the extension has remained deployed for the past 5 years for the purposes of viewing past code changes and the discussions/reviews attached to them. The availability of these discussions are important to future software development.
**Commits since 12 months ago**: 58 commits. (not including Localisation updates).
**Commits since abandonment** (September 2013): 131 commits. This is without counting Localisation updates. Including those, there were 477 commits from December 2013 to June 2018 (`git log --oneline --no-merges '000b8db40fdfa8256...' | wc -l`)
**Developers who committed code in the last 12 months:** 11 commit authors (not including Localisation updates and Libraryupgrader)
**Number, severity, and age of known and confirmed security issues**:
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**Was it a cause of production outages or incidents?**:
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**Does it have sufficient hardware resources for now and the near future?**:
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**Is it a frequent cause of monitoring alerts that need action, and are they addressed timely and appropriately?**:
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**Usage statistics based on audience(s) served:**
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**Number and age of open patches**:
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**Number and age of open bugs**:
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**Submitter's recommendation** (@Krinkle):
Undeploy the extension, but before we can do that, we should preserve the content worth preserving and set up redirects.
The most valuable content is imho the code review discussions. For example, <https://www.mediawiki.org/wiki/Special:Code/MediaWiki/103711#code-comments>.
We'd need to development of a way to export these pages as static HTML, and decide how redirect the urls.
Rough notes:
* Maybe a maintenance script to render the pages without the skin (like action=render, except that doesn't work on special pages currently).
* Redirect urls using Apache rewrites? Remember that we support both `Code/MediaWiki/r1` and `Code/MediaWiki/1` as url pattern.
* Rough proof of concept: <https://codepen.io/Krinkle/full/ERbQQZ/>
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>>! @MaxSem wrote in October 2015:
> We're not using this extension for anything but code review archives anymore, however it has received 18 maintenance commits in 2015 so far which means that it's not free to keep it up forever. Therefore, I propose to make a static dump of it and undeploy.