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  * @file
   9  */
  10
  11 class GitInfo {
  12
  13         /**
  14          * Singleton for the repo at $IP
  15          */
  16         protected static $repo = null;
  17
  18         /**
  19          * Location of the .git directory
  20          */
  21         protected $basedir;
  22
  23         /**
  24          * Map of repo URLs to viewer URLs. Access via static method getViewers().
  25          */
  26         private static $viewers = false;
  27
  28         /**
  29          * @param $dir string The root directory of the repo where the .git dir can be found
  30          */
  31         public function __construct( $dir ) {
  32                 $this->basedir = "{$dir}/.git/";
  33         }
  34
  35         /**
  36          * Return a singleton for the repo at $IP
  37          * @return GitInfo
  38          */
  39         public static function repo() {
  40                 global $IP;
  41                 if ( is_null( self::$repo ) ) {
  42                         self::$repo = new self( $IP );
  43                 }
  44                 return self::$repo;
  45         }
  46
  47         /**
  48          * Check if a string looks like a hex encoded SHA1 hash
  49          *
  50          * @param $str string The string to check
  51          * @return bool Whether or not the string looks like a SHA1
  52          */
  53         public static function isSHA1( $str ) {
  54                 return !!preg_match( '/^[0-9A-F]{40}$/i', $str );
  55         }
  56
  57         /**
  58          * Return the HEAD of the repo (without any opening "ref: ")
  59          * @return string The HEAD
  60          */
  61         public function getHead() {
  62                 $HEADfile = "{$this->basedir}/HEAD";
  63
  64                 if ( !is_readable( $HEADfile ) ) {
  65                         return false;
  66                 }
  67
  68                 $HEAD = file_get_contents( $HEADfile );
  69
  70                 if ( preg_match( "/ref: (.*)/", $HEAD, $m ) ) {
  71                         return rtrim( $m[1] );
  72                 } else {
  73                         return rtrim( $HEAD );
  74                 }
  75         }
  76
  77         /**
  78          * Return the SHA1 for the current HEAD of the repo
  79          * @return string A SHA1 or false
  80          */
  81         public function getHeadSHA1() {
  82                 $HEAD = $this->getHead();
  83
  84                 // If detached HEAD may be a SHA1
  85                 if ( self::isSHA1( $HEAD ) ) {
  86                         return $HEAD;
  87                 }
  88
  89                 // If not a SHA1 it may be a ref:
  90                 $REFfile = "{$this->basedir}{$HEAD}";
  91                 if ( !is_readable( $REFfile ) ) {
  92                         return false;
  93                 }
  94
  95                 $sha1 = rtrim( file_get_contents( $REFfile ) );
  96
  97                 return $sha1;
  98         }
  99
 100         /**
 101          * Return the name of the current branch, or HEAD if not found
 102          * @return string The branch name, HEAD, or false
 103          */
 104         public function getCurrentBranch() {
 105                 $HEAD = $this->getHead();
 106                 if ( $HEAD && preg_match( "#^refs/heads/(.*)$#", $HEAD, $m ) ) {
 107                         return $m[1];
 108                 } else {
 109                         return $HEAD;
 110                 }
 111         }
 112
 113         /**
 114          * Get an URL to a web viewer link to the HEAD revision.
 115          *
 116          * @return string|bool string if an URL is available or false otherwise.
 117          */
 118         public function getHeadViewUrl() {
 119                 $config = "{$this->basedir}/config";
 120                 if ( !is_readable( $config ) ) {
 121                         return false;
 122                 }
 123
 124                 $configArray = parse_ini_file( $config, true );
 125                 $remote = false;
 126
 127                 // Use the "origin" remote repo if available or any other repo if not.
 128                 if ( isset( $configArray['remote origin'] ) ) {
 129                         $remote = $configArray['remote origin'];
 130                 } else {
 131                         foreach( $configArray as $sectionName => $sectionConf ) {
 132                                 if ( substr( $sectionName, 0, 6 ) == 'remote' ) {
 133                                         $remote = $sectionConf;
 134                                 }
 135                         }
 136                 }
 137
 138                 if ( $remote === false || !isset( $remote['url'] ) ) {
 139                         return false;
 140                 }
 141
 142                 $url = $remote['url'];
 143                 if ( substr( $url, -4 ) !== '.git' ) {
 144                         $url .= '.git';
 145                 }
 146                 foreach( self::getViewers() as $repo => $viewer ) {
 147                         $pattern = '#^' . $repo . '$#';
 148                         if ( preg_match( $pattern, $url ) ) {
 149                                 $viewerUrl = preg_replace( $pattern, $viewer, $url );
 150                                 $headSHA1 = $this->getHeadSHA1();
 151                                 $replacements = array(
 152                                         '%h' => substr( $headSHA1, 0, 7 ),
 153                                         '%H' => $headSHA1
 154                                 );
 155                                 return strtr( $viewerUrl, $replacements );
 156                         }
 157                 }
 158                 return false;
 159         }
 160
 161         /**
 162          * @see self::getHeadSHA1
 163          * @return string
 164          */
 165         public static function headSHA1() {
 166                 return self::repo()->getHeadSHA1();
 167         }
 168
 169         /**
 170          * @see self::getCurrentBranch
 171          * @return string
 172          */
 173         public static function currentBranch() {
 174                 return self::repo()->getCurrentBranch();
 175         }
 176
 177         /**
 178          * @see self::getHeadViewUrl()
 179          * @return bool|string
 180          */
 181         public static function headViewUrl() {
 182                 return self::repo()->getHeadViewUrl();
 183         }
 184
 185         /**
 186          * Gets the list of repository viewers
 187          * @return array
 188          */
 189         protected static function getViewers() {
 190                 global $wgGitRepositoryViewers;
 191
 192                 if( self::$viewers === false ) {
 193                         self::$viewers = $wgGitRepositoryViewers;
 194                         wfRunHooks( 'GitViewers', array( &self::$viewers ) );
 195                 }
 196
 197                 return self::$viewers;
 198         }
 199 }