== MediaWiki 1.28 ==

THIS IS NOT A RELEASE YET

MediaWiki 1.28 is an alpha-quality branch and is not recommended for use in
production.

=== Changes since 1.28.0rc0 ===
* (T142210) The changes to move the parser "NewPP limit report" from a HTML
  comment to a machine-readable JavaScript config option 'wgPageParseReport'
  have been undone. They caused the human-readable limit report to be shown
  incompletely or not at all. ParserOutput::setLimitReportData() and
  getLimitReportData() behave as they did in MediaWiki 1.27 again.
* (T149510) Value of {{DISPLAYTITLE:}} parser function will not be used for
  the text of subheadings on a category page when creating it. This wasn't
  working correctly.
* (T106793) MediaWiki will no longer try to perform a HTTP redirect to the
  canonical pretty URL when a non-pretty URL is used. It resulted in redirect
  loops in some clients and in some server configurations. This undoes a change
  made in MediaWiki 1.26.
* (T149759) manifest_version: 2 was removed.

=== Configuration changes in 1.28 ===
* $wgSend404Code now affects status code of action=history if the page is not there.
* BREAKING CHANGE: $wgHTTPProxy is now *required* for all external requests
  made by MediaWiki via a proxy. Relying on the http_proxy environment
  variable is no longer supported.
* The load.php entry point now enforces the existing policy of not allowing
  access to session data, which includes the session user and the session
  user's language. If such access is attempted, an exception will be thrown.
* The number of internal PBKDF2 iterations used to derive the session secret
  is configurable via $wgSessionPbkdf2Iterations.
* Upload dialog's file upload log comment can now be configured separately for
  local and foreign uploads.
* $wgForeignUploadTargets now defaults to `[ 'local' ]`, where `'local'`
  signifies local uploads. A value of `[]` (empty array) now means that
  no upload targets are allowed, effectively disabling the upload dialog.
* The deprecated $wgEditEncoding variable has been removed; it was only used
  for Esperanto language character conversion. You are now recommended to use
  input methods provided by the UniversalLanguageSelector extension.
* When $wgPingback is true, MediaWiki will periodically ping
  https://www.mediawiki.org/beacon with basic information about the local
  MediaWiki installation. This data includes, for example, the type of system,
  PHP version, and chosen database backend. This behavior is off by default.
* When $wgEditSubmitButtonLabelPublish is true, MediaWiki will label the button
  to store-to-database-and-show-to-others as "Publish page"/"Publish changes";
  if false, the default, they will be "Save page"/"Save changes".
* The 'editcontentmodel' permission is now granted to all logged-in users ('user').
  instead of just administrators ('sysop'). Documentation for this feature is
  available at <https://www.mediawiki.org/wiki/Help:ChangeContentModel>.
* $wgRevisionCacheExpiry is now set to one week by default instead of being disabled.
* Magic links are now disabled by default, and can be re-enabled by modifying the value
  of $wgEnableMagicLinks. Their usage is discouraged, but if they are manually enabled,
  a tracking category will be added to help identify usage and make it easier to migrate
  away from. If you depend upon magic link functionality, it is requested that you comment
  on <https://www.mediawiki.org/wiki/Requests_for_comment/Future_of_magic_links> and
  explain your use case(s).
* New config variable $wgCSPFalsePositiveUrls to control what URLs to ignore
  in upcoming Content-Security-Policy feature's reporting.

=== New features in 1.28 ===
* User::isBot() method for checking if an account is a bot role account.
* Added a new 'slideshow' mode for galleries.
* Added a new hook, 'UserIsBot', to aid in determining if a user is a bot.
* Added a new hook, 'ApiMakeParserOptions', to allow extensions to better
  interact with API parsing.
* Added a new hook, 'UploadVerifyUpload', which can be used to reject a file
  upload. Unlike 'UploadVerifyFile' it provides information about upload comment
  and the file description page, but does not run for uploads to stash.
* (T141604) Extensions can now provide a better error message when their
  maintenance scripts are run without the extension being installed.
* (T8948) Numeric sorting in categories is now supported by setting $wgCategoryCollation
  to 'uca-default-u-kn' or 'uca-<langcode>-u-kn'. If you can't use UCA collations,
  a 'numeric' collation is also available. If migrating from another
  collation, you will need to run the updateCollation.php maintenance script.
* Two new codes have been added to #time parser function: "xit" for days in current
  month, and "xiz" for days passed in the year, both in Iranian calendar.
* mw.Api has a new option, useUS, to use U+001F (Unit Separator) when
  appropriate for sending multi-valued parameters. This defaults to true when
  the mw.Api instance seems to be for the local wiki.
* After a client performs an action which alters a database that has replica databases,
  MediaWiki will wait for the replica databases to synchronize with the master database
  while it renders the HTML output. However, if the output is a redirect to another wiki
  on the wiki farm with a different domain, MediaWiki will instead alter the redirect
  URL to include a ?cpPosTime parameter that triggers the database synchronization when
  the URL is followed by the client. The same-domain case uses a new cpPosTime cookie.
* Added new hooks, 'ApiQueryBaseBeforeQuery', 'ApiQueryBaseAfterQuery', and
  'ApiQueryBaseProcessRow', to make it easier for extensions to add 'prop' and
  'show' parameters to existing API query modules.

=== External library changes in 1.28 ===

==== Upgraded external libraries ====
* Updated es5-shim from v4.1.5 to v4.5.8
* Updated composer/semver from v1.4.1 to v1.4.2
* Updated wikimedia/php-session-serializer from v1.0.3 to v1.0.4

==== New external libraries ====
* Added wikimedia/scoped-callback v1.0.0
* Added wikimedia/wait-condition-loop v1.0.1

=== Bug fixes in 1.28 ===
* (T146496) action=history pages should return 404 HTTP error code if the page does not exist
* (T137264) SECURITY: XSS in unclosed internal links
* (T133147) SECURITY: Escape '<' and ']]>' in inline <style> blocks
* (T133147) SECURITY: Require login to preview user CSS pages
* (T132926) SECURITY: Do not allow undeleting a revision deleted file if it is
  the top file
* (T129738) SECURITY: Make $wgBlockDisablesLogin also restrict logged in
  permissions
* (T129738) SECURITY: Make blocks log users out if $wgBlockDisablesLogin is true
* (T139670) Move 'UserGetRights' call before application of
  Session::getAllowedUserRights()

=== Action API changes in 1.28 ===
* Added 'maxarticlesize' property to action=query&meta=siteinfo which contains
  the value of $wgMaxArticleSize.
* Property 'modulemessages' from action=parse&prop=modules was removed
  (deprecated since 1.26).
* The following response properties from action=login, deprecated in 1.27, are
  now removed: lgtoken, cookieprefix, sessionid. Clients should handle cookies
  to properly manage session state.
* Submitting the lgtoken and lgpassword parameters in the query string to
  action=login is now deprecated and outputs a warning. They should be submitted
  in the POST body instead.
* Submitting sensitive authentication request parameters to action=clientlogin,
  action=createaccount, action=linkaccount, and action=changeauthenticationdata
  in the query string is now deprecated and outputs a warning. They should be
  submitted in the POST body instead.
* (T141960) Multi-valued parameters may now be separated using U+001F (Unit Separator)
  instead of the pipe character. This will be useful if some of the multiple
  values need to contain pipes, e.g. for action=options.
* The API will now warn if input is not NFC-normalized Unicode or if it
  contains invalid characters.
* The 'normalized' list output by action=query and other modules that use
  ApiPageSet may contain entries where the 'from' value is percent-encoded as
  the raw value cannot be represented in a valid API response. These are
  indicated by a 'fromencoded' boolean alongside the existing 'from' parameter.
* (T28680) action=paraminfo can now return info about all submodules of a
  module without listing them all explicitly.
* (T146770) It is now possible to assert that the current user is a specific
  named user, using the 'assertuser' parameter.
* (T141963) Added a 'known' property when missing-but-known titles (e.g. from
  the 'TitleIsAlwaysKnown' hook) are output in various modules.

=== Action API internal changes in 1.28 ===
* Added a new hook, 'ApiMakeParserOptions', to allow extensions to better
  interact with ApiParse and ApiExpandTemplates.
* (T139565) SECURITY: API: Generate head items in the context of the given title
* (T115333) SECURITY: Check read permission when loading page content in ApiParse
* ApiBase::getResultData() was removed (deprecated since 1.25)
* ApiBase::makeHelpArrayToString() was removed (deprecated since 1.25)
* ApiBase::makeHelpMsgParameters() was removed (deprecated since 1.25)
* ApiBase::makeHelpMsg() was removed (deprecated since 1.25)
* ApiFormatBase::formatHTML() was removed (deprecated since 1.25)
* ApiFormatBase::getNeedsRawData() was removed (deprecated since 1.25)
* ApiFormatBase::getWantsHelp() was removed (deprecated since 1.25)
* ApiFormatBase::setBufferResult() was removed (deprecated since 1.25)
* ApiFormatBase::setHelp() was removed (deprecated since 1.25)
* ApiFormatBase::setUnescapeAmps() was removed (deprecated since 1.25)
* ApiMain::makeHelpMsgHeader() was removed (deprecated since 1.25)
* ApiMain::reallyMakeHelpMsg() was removed (deprecated since 1.25)
* ApiMain::setHelp() was removed (deprecated since 1.25)
* ApiResult::beginContinuation() was removed (deprecated since 1.25)
* ApiResult::cleanUpUTF8() was removed (deprecated since 1.25)
* ApiResult::convertStatusToArray() was removed (deprecated since 1.25)
* ApiResult::disableSizeCheck() was removed (deprecated since 1.24)
* ApiResult::enableSizeCheck() was removed (deprecated since 1.24)
* ApiResult::endContinuation() was removed (deprecated since 1.25)
* ApiResult::getData() was removed (deprecated since 1.25)
* ApiResult::getIsRawMode() was removed (deprecated since 1.25)
* ApiResult::setContent() was removed (deprecated since 1.25)
* ApiResult::setContinueParam() was removed (deprecated since 1.25)
* ApiResult::setElement() was removed (deprecated since 1.25)
* ApiResult::setGeneratorContinueParam() was removed (deprecated since 1.25)
* ApiResult::setIndexedTagName_internal() was removed (deprecated since 1.25)
* ApiResult::setIndexedTagName_recursive() was removed (deprecated since 1.25)
* ApiResult::setMainForContinuation() was removed (deprecated since 1.25)
* ApiResult::setParsedLimit() was removed (deprecated since 1.25)
* ApiResult::setRawMode() was removed (deprecated since 1.25)
* ApiResult::size() was removed (deprecated since 1.25)
* Added new hooks, 'ApiQueryBaseBeforeQuery', 'ApiQueryBaseAfterQuery', and
  'ApiQueryBaseProcessRow', to make it easier for extensions to add 'prop' and
  'show' parameters to existing API query modules. A query module can enable
  these hooks by passing an array for $hookData to ApiQueryBase::select() and
  by calling ApiQueryBase->processRow() before adding a row's data to the
  result.

=== Languages updated in 1.28 ===

MediaWiki supports over 375 languages. Many localisations are updated
regularly. Below only new and removed languages are listed, as well as
changes to languages because of Phabricator reports.

* (T137411) ban (Balinese), thanks to translators Adi Mayndra, Andru,
  BASAbali, M. Adiputra, Naval Scene, Nemo bis, NoiX180, and 아라.
* (T135867) shn (Shan), thanks to translators Khun Sar, Piangpha,
  Saiddzone Saimawnkham, Saosukham, and Sengwan.
* Czech (cs) and Slovak (sk) set as reciprocal fallbacks.
* (T146744) Livvi-Karelian (olo) namespace messages created thanks to translator Ilja.mos.

=== Other changes in 1.28 ===
* (T128697) Improved handling of large diffs.
* [BREAKING CHANGE] $wgExtendedLoginCookies has been removed. You can
  use or update a custom session provider if needed.
* Deprecated APIEditBeforeSave hook in favor of EditFilterMergedContent.
* The 'UploadVerification' hook is deprecated. Use 'UploadVerifyFile' instead.
* SiteConfiguration::isLocalVHost() was removed (deprecated since 1.25).
* The 'UserLoginComplete' hook has a new parameter to differentiate between actual
  login and visiting the login page while already logged in.
* ResourceLoader::makeLoaderURL() was removed (deprecated since 1.24).
* $.fn.liveAndTestAtStart was removed (deprecated since 1.24).
* mw.util.tooltipAccessKeyPrefix was removed (deprecated since 1.24).
* mw.util.tooltipAccessKeyRegexp was removed (deprecated since 1.24).
* Linker::link() and Linker::linkKnown() were deprecated; please instead use
  MediaWiki\Linker\LinkRenderer. In addition, the LinkBegin and LinkEnd hooks
  were replaced by HtmlPageLinkRendererBegin and HtmlPageLinkRendererEnd
  respectively. See docs/hooks.txt for the specific changes needed for those hooks.
* Linker::formatSize() was deprecated. Use Language::formatSize() directly.
* Aliases for Linker methods, deprecated since 1.21, were removed from Skin:
  * Skin::commentBlock() (use Linker::commentBlock() instead)
  * Skin::generateRollback() (use Linker::generateRollback() instead)
  * Skin::link() (use MediaWiki\Linker\LinkRenderer instead)
  * Skin::linkKnown() (use MediaWiki\Linker\LinkRenderer instead)
  * Skin::userLink() (use Linker::userLink() instead)
  * Skin::userToolLinks() (use Linker::userToolLinks() instead)
* Disabled "bug 2702" HTML tidying of parsed UI messages on wikis where Tidy is
  disabled.
* DifferenceEngine::generateDiffBody() was removed (deprecated since 1.21).
* UploadBase::stashFileGetKey() and UploadBase::stashSession() were deprecated.
  Use ...->stashFile()->getFileKey() instead.
* "Public domain" was removed as a wiki license option from the installer, in
  favour of CC-0.
* AuthenticationRequest::$required is now changed from REQUIRED to PRIMARY_REQUIRED
  on requests needed by primary providers even if all primaries need them.
  Primary providers are discouraged from returning multiple REQUIRED requests.
* OOjs UI PHP widgets constructed with the `'infusable' => true` config option
  will no longer be automatically infused. You should call `OO.ui.infuse()`
  on them yourself from your JavaScript code.
* parserTests.php has moved to tests/parser/parserTests.php
* The command line options specific to parser tests have been removed from
  phpunit.php: --regex and --keep-uploads. Instead of --regex, use --filter.
  Instead of --keep-uploads, use the same option to parserTests.php, but you
  must specify a directory with --upload-dir.
* The 'jquery.arrowSteps' ResourceLoader module is now deprecated.
* IP::isConfiguredProxy() and IP::isTrustedProxy() were removed. Callers should
  migrate to using the same functions on a ProxyLookup instance, obtainable from
  MediaWikiServices.
* The ArticleAfterFetchContent, ArticleInsertComplete, ArticleSave, ArticleSaveComplete,
  ArticleViewCustom, EditFilterMerged, EditPageGetDiffText, EditPageGetPreviewText and
  ShowRawCssJs hooks will now emit deprecation warnings if used.
* (T68404) CSS3 attr() function with url type is no longer allowed
  in inline styles.
* Database::getSearchEngine() is deprecated, use SearchEngineFactory::getSearchEngineClass
  instead.

== Compatibility ==

MediaWiki 1.28 requires PHP 5.5.9 or later. There is experimental support for
HHVM 3.6.5 or later.

MySQL is the recommended DBMS. PostgreSQL or SQLite can also be used, but
support for them is somewhat less mature. There is experimental support for
Oracle and Microsoft SQL Server.

The supported versions are:

* MySQL 5.0.3 or later
* PostgreSQL 8.3 or later
* SQLite 3.3.7 or later
* Oracle 9.0.1 or later
* Microsoft SQL Server 2005 (9.00.1399)

== Upgrading ==

1.28 has several database changes since 1.27, and will not work without schema
updates. Note that due to changes to some very large tables like the revision
table, the schema update may take quite long (minutes on a medium sized site,
many hours on a large site).

If upgrading from before 1.11, and you are using a wiki as a commons
repository, make sure that it is updated as well. Otherwise, errors may arise
due to database schema changes.

If upgrading from before 1.7, you may want to run refreshLinks.php to ensure
new database fields are filled with data.

If you are upgrading from MediaWiki 1.4.x or earlier, you should upgrade to
1.5 first. The upgrade script maintenance/upgrade1_5.php has been removed
with MediaWiki 1.21.

Don't forget to always back up your database before upgrading!

See the file UPGRADE for more detailed upgrade instructions.

For notes on 1.27.x and older releases, see HISTORY.

== Online documentation ==

Documentation for both end-users and site administrators is available on
MediaWiki.org, and is covered under the GNU Free Documentation License (except
for pages that explicitly state that their contents are in the public domain):

       https://www.mediawiki.org/wiki/Special:MyLanguage/Documentation

== Mailing list ==

A mailing list is available for MediaWiki user support and discussion:

       https://lists.wikimedia.org/mailman/listinfo/mediawiki-l

A low-traffic announcements-only list is also available:

       https://lists.wikimedia.org/mailman/listinfo/mediawiki-announce

It's highly recommended that you sign up for one of these lists if you're
going to run a public MediaWiki, so you can be notified of security fixes.

== IRC help ==

There's usually someone online in #mediawiki on irc.freenode.net.
