includes/api/ApiResult.php

   1 <?php
   2
   3 /*
   4  * Created on Sep 4, 2006
   5  *
   6  * API for MediaWiki 1.8+
   7  *
   8  * Copyright (C) 2006 Yuri Astrakhan <Firstname><Lastname>@gmail.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License along
  21  * with this program; if not, write to the Free Software Foundation, Inc.,
  22  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  * http://www.gnu.org/copyleft/gpl.html
  24  */
  25
  26 if ( !defined( 'MEDIAWIKI' ) ) {
  27         // Eclipse helper - will be ignored in production
  28         require_once ( 'ApiBase.php' );
  29 }
  30
  31 /**
  32  * This class represents the result of the API operations.
  33  * It simply wraps a nested array() structure, adding some functions to simplify array's modifications.
  34  * As various modules execute, they add different pieces of information to this result,
  35  * structuring it as it will be given to the client.
  36  *
  37  * Each subarray may either be a dictionary - key-value pairs with unique keys,
  38  * or lists, where the items are added using $data[] = $value notation.
  39  *
  40  * There are two special key values that change how XML output is generated:
  41  *   '_element' This key sets the tag name for the rest of the elements in the current array.
  42  *              It is only inserted if the formatter returned true for getNeedsRawData()
  43  *   '*'        This key has special meaning only to the XML formatter, and is outputed as is
  44  *                              for all others. In XML it becomes the content of the current element.
  45  *
  46  * @ingroup API
  47  */
  48 class ApiResult extends ApiBase {
  49
  50         private $mData, $mIsRawMode, $mSize, $mCheckingSize;
  51
  52         /**
  53          * Constructor
  54          * @param $main ApiMain object
  55          */
  56         public function __construct( $main ) {
  57                 parent :: __construct( $main, 'result' );
  58                 $this->mIsRawMode = false;
  59                 $this->mCheckingSize = true;
  60                 $this->reset();
  61         }
  62
  63         /**
  64          * Clear the current result data.
  65          */
  66         public function reset() {
  67                 $this->mData = array ();
  68                 $this->mSize = 0;
  69         }
  70
  71         /**
  72          * Call this function when special elements such as '_element'
  73          * are needed by the formatter, for example in XML printing.
  74          */
  75         public function setRawMode() {
  76                 $this->mIsRawMode = true;
  77         }
  78
  79         /**
  80          * Returns true whether the formatter requested raw data.
  81          * @return bool
  82          */
  83         public function getIsRawMode() {
  84                 return $this->mIsRawMode;
  85         }
  86
  87         /**
  88          * Get the result's internal data array (read-only)
  89          * @return array
  90          */
  91         public function getData() {
  92                 return $this->mData;
  93         }
  94
  95         /**
  96          * Get the 'real' size of a result item. This means the strlen() of the item,
  97          * or the sum of the strlen()s of the elements if the item is an array.
  98          * @param $value mixed
  99          * @return int
 100          */
 101         public static function size( $value ) {
 102                 $s = 0;
 103                 if ( is_array( $value ) )
 104                         foreach ( $value as $v )
 105                                 $s += self::size( $v );
 106                 else if ( !is_object( $value ) )
 107                         // Objects can't always be cast to string
 108                         $s = strlen( $value );
 109                 return $s;
 110         }
 111
 112         /**
 113          * Get the size of the result, i.e. the amount of bytes in it
 114          * @return int
 115          */
 116         public function getSize() {
 117                 return $this->mSize;
 118         }
 119
 120         /**
 121          * Disable size checking in addValue(). Don't use this unless you
 122          * REALLY know what you're doing. Values added while size checking
 123          * was disabled will not be counted (ever)
 124          */
 125         public function disableSizeCheck() {
 126                 $this->mCheckingSize = false;
 127         }
 128
 129         /**
 130          * Re-enable size checking in addValue()
 131          */
 132         public function enableSizeCheck() {
 133                 $this->mCheckingSize = true;
 134         }
 135
 136         /**
 137          * Add an output value to the array by name.
 138          * Verifies that value with the same name has not been added before.
 139          * @param $arr array to add $value to
 140          * @param $name string Index of $arr to add $value at
 141          * @param $value mixed
 142          */
 143         public static function setElement( & $arr, $name, $value ) {
 144                 if ( $arr === null || $name === null || $value === null || !is_array( $arr ) || is_array( $name ) )
 145                         ApiBase :: dieDebug( __METHOD__, 'Bad parameter' );
 146
 147                 if ( !isset ( $arr[$name] ) ) {
 148                         $arr[$name] = $value;
 149                 }
 150                 elseif ( is_array( $arr[$name] ) && is_array( $value ) ) {
 151                         $merged = array_intersect_key( $arr[$name], $value );
 152                         if ( !count( $merged ) )
 153                                 $arr[$name] += $value;
 154                         else
 155                                 ApiBase :: dieDebug( __METHOD__, "Attempting to merge element $name" );
 156                 } else
 157                         ApiBase :: dieDebug( __METHOD__, "Attempting to add element $name=$value, existing value is {$arr[$name]}" );
 158         }
 159
 160         /**
 161          * Adds a content element to an array.
 162          * Use this function instead of hardcoding the '*' element.
 163          * @param $arr array to add the content element to
 164          * @param $subElemName string when present, content element is created
 165          *  as a sub item of $arr. Use this parameter to create elements in
 166          *  format <elem>text</elem> without attributes
 167          */
 168         public static function setContent( & $arr, $value, $subElemName = null ) {
 169                 if ( is_array( $value ) )
 170                         ApiBase :: dieDebug( __METHOD__, 'Bad parameter' );
 171                 if ( is_null( $subElemName ) ) {
 172                         ApiResult :: setElement( $arr, '*', $value );
 173                 } else {
 174                         if ( !isset ( $arr[$subElemName] ) )
 175                                 $arr[$subElemName] = array ();
 176                         ApiResult :: setElement( $arr[$subElemName], '*', $value );
 177                 }
 178         }
 179
 180         /**
 181          * In case the array contains indexed values (in addition to named),
 182          * give all indexed values the given tag name. This function MUST be
 183          * called on every arrray that has numerical indexes.
 184          * @param $arr array
 185          * @param $tag string Tag name
 186          */
 187         public function setIndexedTagName( & $arr, $tag ) {
 188                 // In raw mode, add the '_element', otherwise just ignore
 189                 if ( !$this->getIsRawMode() )
 190                         return;
 191                 if ( $arr === null || $tag === null || !is_array( $arr ) || is_array( $tag ) )
 192                         ApiBase :: dieDebug( __METHOD__, 'Bad parameter' );
 193                 // Do not use setElement() as it is ok to call this more than once
 194                 $arr['_element'] = $tag;
 195         }
 196
 197         /**
 198          * Calls setIndexedTagName() on each sub-array of $arr
 199          * @param $arr array
 200          * @param $tag string Tag name
 201          */
 202         public function setIndexedTagName_recursive( &$arr, $tag ) {
 203                 if ( !is_array( $arr ) )
 204                                 return;
 205                 foreach ( $arr as &$a )
 206                 {
 207                                 if ( !is_array( $a ) )
 208                                                 continue;
 209                                 $this->setIndexedTagName( $a, $tag );
 210                                 $this->setIndexedTagName_recursive( $a, $tag );
 211                 }
 212         }
 213
 214         /**
 215          * Calls setIndexedTagName() on an array already in the result.
 216          * Don't specify a path to a value that's not in the result, or
 217          * you'll get nasty errors.
 218          * @param $path array Path to the array, like addValue()'s $path
 219          * @param $tag string
 220          */
 221         public function setIndexedTagName_internal( $path, $tag ) {
 222                 $data = & $this->mData;
 223                 foreach ( (array)$path as $p ) {
 224                         if ( !isset( $data[$p] ) ) {
 225                                 $data[$p] = array();
 226                         }
 227                         $data = & $data[$p];
 228                 }
 229                 if ( is_null( $data ) )
 230                         return;
 231                 $this->setIndexedTagName( $data, $tag );
 232         }
 233
 234         /**
 235          * Add value to the output data at the given path.
 236          * Path is an indexed array, each element specifing the branch at which to add the new value
 237          * Setting $path to array('a','b','c') is equivalent to data['a']['b']['c'] = $value
 238          * If $name is empty, the $value is added as a next list element data[] = $value
 239          * @return bool True if $value fits in the result, false if not
 240          */
 241         public function addValue( $path, $name, $value ) {
 242                 global $wgAPIMaxResultSize;
 243                 $data = & $this->mData;
 244                 if ( $this->mCheckingSize ) {
 245                         $newsize = $this->mSize + self::size( $value );
 246                         if ( $newsize > $wgAPIMaxResultSize )
 247                                 return false;
 248                         $this->mSize = $newsize;
 249                 }
 250
 251                 if ( !is_null( $path ) ) {
 252                         if ( is_array( $path ) ) {
 253                                 foreach ( $path as $p ) {
 254                                         if ( !isset ( $data[$p] ) )
 255                                                 $data[$p] = array ();
 256                                         $data = & $data[$p];
 257                                 }
 258                         } else {
 259                                 if ( !isset ( $data[$path] ) )
 260                                         $data[$path] = array ();
 261                                 $data = & $data[$path];
 262                         }
 263                 }
 264
 265                 if ( !$name )
 266                         $data[] = $value;       // Add list element
 267                 else
 268                         ApiResult :: setElement( $data, $name, $value );        // Add named element
 269                 return true;
 270         }
 271
 272         /**
 273          * Unset a value previously added to the result set.
 274          * Fails silently if the value isn't found.
 275          * For parameters, see addValue()
 276          * @param $path array
 277          * @param $name string
 278          */
 279         public function unsetValue( $path, $name ) {
 280                 $data = & $this->mData;
 281                 if ( !is_null( $path ) )
 282                         foreach ( (array)$path as $p ) {
 283                                 if ( !isset( $data[$p] ) )
 284                                         return;
 285                                 $data = & $data[$p];
 286                         }
 287                 $this->mSize -= self::size( $data[$name] );
 288                 unset( $data[$name] );
 289         }
 290
 291         /**
 292          * Ensure all values in this result are valid UTF-8.
 293          */
 294         public function cleanUpUTF8()
 295         {
 296                 array_walk_recursive( $this->mData, array( 'ApiResult', 'cleanUp_helper' ) );
 297         }
 298
 299         /**
 300          * Callback function for cleanUpUTF8()
 301          */
 302         private static function cleanUp_helper( &$s )
 303         {
 304                 if ( !is_string( $s ) )
 305                         return;
 306                 global $wgContLang;
 307                 $s = $wgContLang->normalize( $s );
 308         }
 309
 310         public function execute() {
 311                 ApiBase :: dieDebug( __METHOD__, 'execute() is not supported on Result object' );
 312         }
 313
 314         public function getVersion() {
 315                 return __CLASS__ . ': $Id$';
 316         }
 317 }