includes/api/ApiFormatBase.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on Sep 19, 2006
   6  *
   7  * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  22  * http://www.gnu.org/copyleft/gpl.html
  23  *
  24  * @file
  25  */
  26
  27 /**
  28  * This is the abstract base class for API formatters.
  29  *
  30  * @ingroup API
  31  */
  32 abstract class ApiFormatBase extends ApiBase {
  33
  34         private $mIsHtml, $mFormat, $mUnescapeAmps, $mHelp, $mCleared;
  35         private $mBufferResult = false, $mBuffer, $mDisabled = false;
  36
  37         /**
  38          * Constructor
  39          * If $format ends with 'fm', pretty-print the output in HTML.
  40          * @param $main ApiMain
  41          * @param string $format Format name
  42          */
  43         public function __construct( $main, $format ) {
  44                 parent::__construct( $main, $format );
  45
  46                 $this->mIsHtml = ( substr( $format, - 2, 2 ) === 'fm' ); // ends with 'fm'
  47                 if ( $this->mIsHtml ) {
  48                         $this->mFormat = substr( $format, 0, - 2 ); // remove ending 'fm'
  49                 } else {
  50                         $this->mFormat = $format;
  51                 }
  52                 $this->mFormat = strtoupper( $this->mFormat );
  53                 $this->mCleared = false;
  54         }
  55
  56         /**
  57          * Overriding class returns the mime type that should be sent to the client.
  58          * This method is not called if getIsHtml() returns true.
  59          * @return string
  60          */
  61         abstract public function getMimeType();
  62
  63         /**
  64          * Whether this formatter needs raw data such as _element tags
  65          * @return bool
  66          */
  67         public function getNeedsRawData() {
  68                 return false;
  69         }
  70
  71         /**
  72          * Get the internal format name
  73          * @return string
  74          */
  75         public function getFormat() {
  76                 return $this->mFormat;
  77         }
  78
  79         /**
  80          * Specify whether or not sequences like &amp;quot; should be unescaped
  81          * to &quot; . This should only be set to true for the help message
  82          * when rendered in the default (xmlfm) format. This is a temporary
  83          * special-case fix that should be removed once the help has been
  84          * reworked to use a fully HTML interface.
  85          *
  86          * @param bool $b Whether or not ampersands should be escaped.
  87          */
  88         public function setUnescapeAmps( $b ) {
  89                 $this->mUnescapeAmps = $b;
  90         }
  91
  92         /**
  93          * Returns true when the HTML pretty-printer should be used.
  94          * The default implementation assumes that formats ending with 'fm'
  95          * should be formatted in HTML.
  96          * @return bool
  97          */
  98         public function getIsHtml() {
  99                 return $this->mIsHtml;
 100         }
 101
 102         /**
 103          * Whether this formatter can format the help message in a nice way.
 104          * By default, this returns the same as getIsHtml().
 105          * When action=help is set explicitly, the help will always be shown
 106          * @return bool
 107          */
 108         public function getWantsHelp() {
 109                 return $this->getIsHtml();
 110         }
 111
 112         /**
 113          * Disable the formatter completely. This causes calls to initPrinter(),
 114          * printText() and closePrinter() to be ignored.
 115          */
 116         public function disable() {
 117                 $this->mDisabled = true;
 118         }
 119
 120         public function isDisabled() {
 121                 return $this->mDisabled;
 122         }
 123
 124         /**
 125          * Initialize the printer function and prepare the output headers, etc.
 126          * This method must be the first outputting method during execution.
 127          * A human-targeted notice about available formats is printed for the HTML-based output,
 128          * except for help screens (caused by either an error in the API parameters,
 129          * the calling of action=help, or requesting the root script api.php).
 130          * @param bool $isHelpScreen Whether a help screen is going to be shown
 131          */
 132         function initPrinter( $isHelpScreen ) {
 133                 if ( $this->mDisabled ) {
 134                         return;
 135                 }
 136                 $isHtml = $this->getIsHtml();
 137                 $mime = $isHtml ? 'text/html' : $this->getMimeType();
 138                 $script = wfScript( 'api' );
 139
 140                 // Some printers (ex. Feed) do their own header settings,
 141                 // in which case $mime will be set to null
 142                 if ( is_null( $mime ) ) {
 143                         return; // skip any initialization
 144                 }
 145
 146                 $this->getMain()->getRequest()->response()->header( "Content-Type: $mime; charset=utf-8" );
 147
 148                 //Set X-Frame-Options API results (bug 39180)
 149                 global $wgApiFrameOptions;
 150                 if ( $wgApiFrameOptions ) {
 151                         $this->getMain()->getRequest()->response()->header( "X-Frame-Options: $wgApiFrameOptions" );
 152                 }
 153
 154                 if ( $isHtml ) {
 155 ?>
 156 <!DOCTYPE HTML>
 157 <html>
 158 <head>
 159 <?php if ( $this->mUnescapeAmps ) {
 160 ?>      <title>MediaWiki API</title>
 161 <?php } else {
 162 ?>      <title>MediaWiki API Result</title>
 163 <?php } ?>
 164 </head>
 165 <body>
 166 <?php
 167
 168
 169                         if ( !$isHelpScreen ) {
 170 ?>
 171 <br />
 172 <small>
 173 You are looking at the HTML representation of the <?php echo $this->mFormat; ?> format.<br />
 174 HTML is good for debugging, but is unsuitable for application use.<br />
 175 Specify the format parameter to change the output format.<br />
 176 To see the non HTML representation of the <?php echo $this->mFormat; ?> format, set format=<?php echo strtolower( $this->mFormat ); ?>.<br />
 177 See the <a href='https://www.mediawiki.org/wiki/API'>complete documentation</a>, or
 178 <a href='<?php echo $script; ?>'>API help</a> for more information.
 179 </small>
 180 <pre style='white-space: pre-wrap;'>
 181 <?php
 182
 183
 184                         } else { // don't wrap the contents of the <pre> for help screens
 185                                   // because these are actually formatted to rely on
 186                                   // the monospaced font for layout purposes
 187 ?>
 188 <pre>
 189 <?php
 190
 191                         }
 192                 }
 193         }
 194
 195         /**
 196          * Finish printing. Closes HTML tags.
 197          */
 198         public function closePrinter() {
 199                 if ( $this->mDisabled ) {
 200                         return;
 201                 }
 202                 if ( $this->getIsHtml() ) {
 203 ?>
 204
 205 </pre>
 206 </body>
 207 </html>
 208 <?php
 209
 210
 211                 }
 212         }
 213
 214         /**
 215          * The main format printing function. Call it to output the result
 216          * string to the user. This function will automatically output HTML
 217          * when format name ends in 'fm'.
 218          * @param $text string
 219          */
 220         public function printText( $text ) {
 221                 if ( $this->mDisabled ) {
 222                         return;
 223                 }
 224                 if ( $this->mBufferResult ) {
 225                         $this->mBuffer = $text;
 226                 } elseif ( $this->getIsHtml() ) {
 227                         echo $this->formatHTML( $text );
 228                 } else {
 229                         // For non-HTML output, clear all errors that might have been
 230                         // displayed if display_errors=On
 231                         // Do this only once, of course
 232                         if ( !$this->mCleared ) {
 233                                 ob_clean();
 234                                 $this->mCleared = true;
 235                         }
 236                         echo $text;
 237                 }
 238         }
 239
 240         /**
 241          * Get the contents of the buffer.
 242          */
 243         public function getBuffer() {
 244                 return $this->mBuffer;
 245         }
 246
 247         /**
 248          * Set the flag to buffer the result instead of printing it.
 249          * @param $value bool
 250          */
 251         public function setBufferResult( $value ) {
 252                 $this->mBufferResult = $value;
 253         }
 254
 255         /**
 256          * Sets whether the pretty-printer should format *bold*
 257          * @param $help bool
 258          */
 259         public function setHelp( $help = true ) {
 260                 $this->mHelp = $help;
 261         }
 262
 263         /**
 264          * Pretty-print various elements in HTML format, such as xml tags and
 265          * URLs. This method also escapes characters like <
 266          * @param $text string
 267          * @return string
 268          */
 269         protected function formatHTML( $text ) {
 270                 // Escape everything first for full coverage
 271                 $text = htmlspecialchars( $text );
 272                 // encode all comments or tags as safe blue strings
 273                 $text = str_replace( '&lt;', '<span style="color:blue;">&lt;', $text );
 274                 $text = str_replace( '&gt;', '&gt;</span>', $text );
 275                 // identify requests to api.php
 276                 $text = preg_replace( "#api\\.php\\?[^ <\n\t]+#", '<a href="\\0">\\0</a>', $text );
 277                 if ( $this->mHelp ) {
 278                         // make strings inside * bold
 279                         $text = preg_replace( "#\\*[^<>\n]+\\*#", '<b>\\0</b>', $text );
 280                 }
 281                 // identify URLs
 282                 $protos = wfUrlProtocolsWithoutProtRel();
 283                 // This regex hacks around bug 13218 (&quot; included in the URL)
 284                 $text = preg_replace( "#(((?i)$protos).*?)(&quot;)?([ \\'\"<>\n]|&lt;|&gt;|&quot;)#", '<a href="\\1">\\1</a>\\3\\4', $text );
 285
 286                 /**
 287                  * Temporary fix for bad links in help messages. As a special case,
 288                  * XML-escaped metachars are de-escaped one level in the help message
 289                  * for legibility. Should be removed once we have completed a fully-HTML
 290                  * version of the help message.
 291                  */
 292                 if ( $this->mUnescapeAmps ) {
 293                         $text = preg_replace( '/&amp;(amp|quot|lt|gt);/', '&\1;', $text );
 294                 }
 295
 296                 return $text;
 297         }
 298
 299         public function getExamples() {
 300                 return array(
 301                         'api.php?action=query&meta=siteinfo&siprop=namespaces&format=' . $this->getModuleName()
 302                                 => "Format the query result in the {$this->getModuleName()} format",
 303                 );
 304         }
 305
 306         public function getHelpUrls() {
 307                 return 'https://www.mediawiki.org/wiki/API:Data_formats';
 308         }
 309
 310         public function getDescription() {
 311                 return $this->getIsHtml() ? ' (pretty-print in HTML)' : '';
 312         }
 313 }
 314
 315 /**
 316  * This printer is used to wrap an instance of the Feed class
 317  * @ingroup API
 318  */
 319 class ApiFormatFeedWrapper extends ApiFormatBase {
 320
 321         public function __construct( $main ) {
 322                 parent::__construct( $main, 'feed' );
 323         }
 324
 325         /**
 326          * Call this method to initialize output data. See execute()
 327          * @param $result ApiResult
 328          * @param $feed object an instance of one of the $wgFeedClasses classes
 329          * @param array $feedItems of FeedItem objects
 330          */
 331         public static function setResult( $result, $feed, $feedItems ) {
 332                 // Store output in the Result data.
 333                 // This way we can check during execution if any error has occurred
 334                 // Disable size checking for this because we can't continue
 335                 // cleanly; size checking would cause more problems than it'd
 336                 // solve
 337                 $result->disableSizeCheck();
 338                 $result->addValue( null, '_feed', $feed );
 339                 $result->addValue( null, '_feeditems', $feedItems );
 340                 $result->enableSizeCheck();
 341         }
 342
 343         /**
 344          * Feed does its own headers
 345          *
 346          * @return null
 347          */
 348         public function getMimeType() {
 349                 return null;
 350         }
 351
 352         /**
 353          * Optimization - no need to sanitize data that will not be needed
 354          *
 355          * @return bool
 356          */
 357         public function getNeedsRawData() {
 358                 return true;
 359         }
 360
 361         /**
 362          * This class expects the result data to be in a custom format set by self::setResult()
 363          * $result['_feed']             - an instance of one of the $wgFeedClasses classes
 364          * $result['_feeditems']        - an array of FeedItem instances
 365          */
 366         public function execute() {
 367                 $data = $this->getResultData();
 368                 if ( isset( $data['_feed'] ) && isset( $data['_feeditems'] ) ) {
 369                         $feed = $data['_feed'];
 370                         $items = $data['_feeditems'];
 371
 372                         $feed->outHeader();
 373                         foreach ( $items as & $item ) {
 374                                 $feed->outItem( $item );
 375                         }
 376                         $feed->outFooter();
 377                 } else {
 378                         // Error has occurred, print something useful
 379                         ApiBase::dieDebug( __METHOD__, 'Invalid feed class/item' );
 380                 }
 381         }
 382 }