includes/ReadOnlyMode.php

   1 <?php
   2
   3 use Wikimedia\Rdbms\LoadBalancer;
   4
   5 /**
   6  * A service class for fetching the wiki's current read-only mode.
   7  * To obtain an instance, use MediaWikiServices::getReadOnlyMode().
   8  *
   9  * @since 1.29
  10  */
  11 class ReadOnlyMode {
  12         private $configuredReadOnly;
  13         private $loadBalancer;
  14
  15         public function __construct( ConfiguredReadOnlyMode $cro, LoadBalancer $loadBalancer ) {
  16                 $this->configuredReadOnly = $cro;
  17                 $this->loadBalancer = $loadBalancer;
  18         }
  19
  20         /**
  21          * Check whether the wiki is in read-only mode.
  22          *
  23          * @return bool
  24          */
  25         public function isReadOnly() {
  26                 return $this->getReason() !== false;
  27         }
  28
  29         /**
  30          * Check if the site is in read-only mode and return the message if so
  31          *
  32          * This checks the configuration and registered DB load balancers for
  33          * read-only mode. This may result in DB connection being made.
  34          *
  35          * @return string|bool String when in read-only mode; false otherwise
  36          */
  37         public function getReason() {
  38                 $reason = $this->configuredReadOnly->getReason();
  39                 if ( $reason !== false ) {
  40                         return $reason;
  41                 }
  42                 $reason = $this->loadBalancer->getReadOnlyReason();
  43                 if ( $reason !== false && $reason !== null ) {
  44                         return $reason;
  45                 }
  46                 return false;
  47         }
  48
  49         /**
  50          * Set the read-only mode, which will apply for the remainder of the
  51          * request or until a service reset.
  52          */
  53         public function setReason( $msg ) {
  54                 $this->configuredReadOnly->setReason( $msg );
  55         }
  56
  57         /**
  58          * Clear the cache of the read only file
  59          */
  60         public function clearCache() {
  61                 $this->configuredReadOnly->clearCache();
  62         }
  63 }
  64
  65 /**
  66  * A read-only mode service which does not depend on LoadBalancer.
  67  * To obtain an instance, use MediaWikiServices::getConfiguredReadOnlyMode().
  68  *
  69  * @since 1.29
  70  */
  71 class ConfiguredReadOnlyMode {
  72         private $config;
  73         private $fileReason;
  74         private $overrideReason;
  75
  76         public function __construct( Config $config ) {
  77                 $this->config = $config;
  78         }
  79
  80         /**
  81          * Check whether the wiki is in read-only mode.
  82          *
  83          * @return bool
  84          */
  85         public function isReadOnly() {
  86                 return $this->getReason() !== false;
  87         }
  88
  89         /**
  90          * Get the value of $wgReadOnly or the contents of $wgReadOnlyFile.
  91          *
  92          * @return string|bool String when in read-only mode; false otherwise
  93          */
  94         public function getReason() {
  95                 if ( $this->overrideReason !== null ) {
  96                         return $this->overrideReason;
  97                 }
  98                 $confReason = $this->config->get( 'ReadOnly' );
  99                 if ( $confReason !== null ) {
 100                         return $confReason;
 101                 }
 102                 if ( $this->fileReason === null ) {
 103                         // Cache for faster access next time
 104                         $readOnlyFile = $this->config->get( 'ReadOnlyFile' );
 105                         if ( is_file( $readOnlyFile ) && filesize( $readOnlyFile ) > 0 ) {
 106                                 $this->fileReason = file_get_contents( $readOnlyFile );
 107                         } else {
 108                                 $this->fileReason = false;
 109                         }
 110                 }
 111                 return $this->fileReason;
 112         }
 113
 114         /**
 115          * Set the read-only mode, which will apply for the remainder of the
 116          * request or until a service reset.
 117          */
 118         public function setReason( $msg ) {
 119                 $this->overrideReason = $msg;
 120         }
 121
 122         /**
 123          * Clear the cache of the read only file
 124          */
 125         public function clearCache() {
 126                 $this->fileReason = null;
 127         }
 128 }