includes/GitInfo.php

   1 <?php
   2 /**
   3  * A class to help return information about a git repo MediaWiki may be inside
   4  * This is used by Special:Version and is also useful for the LocalSettings.php
   5  * of anyone working on large branches in git to setup config that show up only
   6  * when specific branches are currently checked out.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  21  * http://www.gnu.org/copyleft/gpl.html
  22  *
  23  * @file
  24  */
  25
  26 class GitInfo {
  27
  28         /**
  29          * Singleton for the repo at $IP
  30          */
  31         protected static $repo = null;
  32
  33         /**
  34          * Location of the .git directory
  35          */
  36         protected $basedir;
  37
  38         /**
  39          * Map of repo URLs to viewer URLs. Access via static method getViewers().
  40          */
  41         private static $viewers = false;
  42
  43         /**
  44          * @param $dir string The root directory of the repo where the .git dir can be found
  45          */
  46         public function __construct( $dir ) {
  47                 $this->basedir = "{$dir}/.git/";
  48         }
  49
  50         /**
  51          * Return a singleton for the repo at $IP
  52          * @return GitInfo
  53          */
  54         public static function repo() {
  55                 global $IP;
  56                 if ( is_null( self::$repo ) ) {
  57                         self::$repo = new self( $IP );
  58                 }
  59                 return self::$repo;
  60         }
  61
  62         /**
  63          * Check if a string looks like a hex encoded SHA1 hash
  64          *
  65          * @param $str string The string to check
  66          * @return bool Whether or not the string looks like a SHA1
  67          */
  68         public static function isSHA1( $str ) {
  69                 return !!preg_match( '/^[0-9A-F]{40}$/i', $str );
  70         }
  71
  72         /**
  73          * Return the HEAD of the repo (without any opening "ref: ")
  74          * @return string The HEAD
  75          */
  76         public function getHead() {
  77                 $HEADfile = "{$this->basedir}/HEAD";
  78
  79                 if ( !is_readable( $HEADfile ) ) {
  80                         return false;
  81                 }
  82
  83                 $HEAD = file_get_contents( $HEADfile );
  84
  85                 if ( preg_match( "/ref: (.*)/", $HEAD, $m ) ) {
  86                         return rtrim( $m[1] );
  87                 } else {
  88                         return rtrim( $HEAD );
  89                 }
  90         }
  91
  92         /**
  93          * Return the SHA1 for the current HEAD of the repo
  94          * @return string A SHA1 or false
  95          */
  96         public function getHeadSHA1() {
  97                 $HEAD = $this->getHead();
  98
  99                 // If detached HEAD may be a SHA1
 100                 if ( self::isSHA1( $HEAD ) ) {
 101                         return $HEAD;
 102                 }
 103
 104                 // If not a SHA1 it may be a ref:
 105                 $REFfile = "{$this->basedir}{$HEAD}";
 106                 if ( !is_readable( $REFfile ) ) {
 107                         return false;
 108                 }
 109
 110                 $sha1 = rtrim( file_get_contents( $REFfile ) );
 111
 112                 return $sha1;
 113         }
 114
 115         /**
 116          * Return the name of the current branch, or HEAD if not found
 117          * @return string The branch name, HEAD, or false
 118          */
 119         public function getCurrentBranch() {
 120                 $HEAD = $this->getHead();
 121                 if ( $HEAD && preg_match( "#^refs/heads/(.*)$#", $HEAD, $m ) ) {
 122                         return $m[1];
 123                 } else {
 124                         return $HEAD;
 125                 }
 126         }
 127
 128         /**
 129          * Get an URL to a web viewer link to the HEAD revision.
 130          *
 131          * @return string|bool string if an URL is available or false otherwise.
 132          */
 133         public function getHeadViewUrl() {
 134                 $config = "{$this->basedir}/config";
 135                 if ( !is_readable( $config ) ) {
 136                         return false;
 137                 }
 138
 139                 $configArray = parse_ini_file( $config, true );
 140                 $remote = false;
 141
 142                 // Use the "origin" remote repo if available or any other repo if not.
 143                 if ( isset( $configArray['remote origin'] ) ) {
 144                         $remote = $configArray['remote origin'];
 145                 } else {
 146                         foreach( $configArray as $sectionName => $sectionConf ) {
 147                                 if ( substr( $sectionName, 0, 6 ) == 'remote' ) {
 148                                         $remote = $sectionConf;
 149                                 }
 150                         }
 151                 }
 152
 153                 if ( $remote === false || !isset( $remote['url'] ) ) {
 154                         return false;
 155                 }
 156
 157                 $url = $remote['url'];
 158                 if ( substr( $url, -4 ) !== '.git' ) {
 159                         $url .= '.git';
 160                 }
 161                 foreach( self::getViewers() as $repo => $viewer ) {
 162                         $pattern = '#^' . $repo . '$#';
 163                         if ( preg_match( $pattern, $url ) ) {
 164                                 $viewerUrl = preg_replace( $pattern, $viewer, $url );
 165                                 $headSHA1 = $this->getHeadSHA1();
 166                                 $replacements = array(
 167                                         '%h' => substr( $headSHA1, 0, 7 ),
 168                                         '%H' => $headSHA1
 169                                 );
 170                                 return strtr( $viewerUrl, $replacements );
 171                         }
 172                 }
 173                 return false;
 174         }
 175
 176         /**
 177          * @see self::getHeadSHA1
 178          * @return string
 179          */
 180         public static function headSHA1() {
 181                 return self::repo()->getHeadSHA1();
 182         }
 183
 184         /**
 185          * @see self::getCurrentBranch
 186          * @return string
 187          */
 188         public static function currentBranch() {
 189                 return self::repo()->getCurrentBranch();
 190         }
 191
 192         /**
 193          * @see self::getHeadViewUrl()
 194          * @return bool|string
 195          */
 196         public static function headViewUrl() {
 197                 return self::repo()->getHeadViewUrl();
 198         }
 199
 200         /**
 201          * Gets the list of repository viewers
 202          * @return array
 203          */
 204         protected static function getViewers() {
 205                 global $wgGitRepositoryViewers;
 206
 207                 if( self::$viewers === false ) {
 208                         self::$viewers = $wgGitRepositoryViewers;
 209                         wfRunHooks( 'GitViewers', array( &self::$viewers ) );
 210                 }
 211
 212                 return self::$viewers;
 213         }
 214 }