includes/api/ApiResult.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on Sep 4, 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 if ( !defined( 'MEDIAWIKI' ) ) {
  28         // Eclipse helper - will be ignored in production
  29         require_once( 'ApiBase.php' );
  30 }
  31
  32 /**
  33  * This class represents the result of the API operations.
  34  * It simply wraps a nested array() structure, adding some functions to simplify array's modifications.
  35  * As various modules execute, they add different pieces of information to this result,
  36  * structuring it as it will be given to the client.
  37  *
  38  * Each subarray may either be a dictionary - key-value pairs with unique keys,
  39  * or lists, where the items are added using $data[] = $value notation.
  40  *
  41  * There are two special key values that change how XML output is generated:
  42  *   '_element' This key sets the tag name for the rest of the elements in the current array.
  43  *              It is only inserted if the formatter returned true for getNeedsRawData()
  44  *   '*'        This key has special meaning only to the XML formatter, and is outputed as is
  45  *                              for all others. In XML it becomes the content of the current element.
  46  *
  47  * @ingroup API
  48  */
  49 class ApiResult extends ApiBase {
  50
  51         private $mData, $mIsRawMode, $mSize, $mCheckingSize;
  52
  53         /**
  54          * Constructor
  55          * @param $main ApiMain object
  56          */
  57         public function __construct( $main ) {
  58                 parent::__construct( $main, 'result' );
  59                 $this->mIsRawMode = false;
  60                 $this->mCheckingSize = true;
  61                 $this->reset();
  62         }
  63
  64         /**
  65          * Clear the current result data.
  66          */
  67         public function reset() {
  68                 $this->mData = array();
  69                 $this->mSize = 0;
  70         }
  71
  72         /**
  73          * Call this function when special elements such as '_element'
  74          * are needed by the formatter, for example in XML printing.
  75          */
  76         public function setRawMode() {
  77                 $this->mIsRawMode = true;
  78         }
  79
  80         /**
  81          * Returns true whether the formatter requested raw data.
  82          * @return bool
  83          */
  84         public function getIsRawMode() {
  85                 return $this->mIsRawMode;
  86         }
  87
  88         /**
  89          * Get the result's internal data array (read-only)
  90          * @return array
  91          */
  92         public function getData() {
  93                 return $this->mData;
  94         }
  95
  96         /**
  97          * Get the 'real' size of a result item. This means the strlen() of the item,
  98          * or the sum of the strlen()s of the elements if the item is an array.
  99          * @param $value mixed
 100          * @return int
 101          */
 102         public static function size( $value ) {
 103                 $s = 0;
 104                 if ( is_array( $value ) ) {
 105                         foreach ( $value as $v ) {
 106                                 $s += self::size( $v );
 107                         }
 108                 } elseif ( !is_object( $value ) ) {
 109                         // Objects can't always be cast to string
 110                         $s = strlen( $value );
 111                 }
 112                 return $s;
 113         }
 114
 115         /**
 116          * Get the size of the result, i.e. the amount of bytes in it
 117          * @return int
 118          */
 119         public function getSize() {
 120                 return $this->mSize;
 121         }
 122
 123         /**
 124          * Disable size checking in addValue(). Don't use this unless you
 125          * REALLY know what you're doing. Values added while size checking
 126          * was disabled will not be counted (ever)
 127          */
 128         public function disableSizeCheck() {
 129                 $this->mCheckingSize = false;
 130         }
 131
 132         /**
 133          * Re-enable size checking in addValue()
 134          */
 135         public function enableSizeCheck() {
 136                 $this->mCheckingSize = true;
 137         }
 138
 139         /**
 140          * Add an output value to the array by name.
 141          * Verifies that value with the same name has not been added before.
 142          * @param $arr array to add $value to
 143          * @param $name string Index of $arr to add $value at
 144          * @param $value mixed
 145          * @param $overwrite bool Whether overwriting an existing element is allowed
 146          */
 147         public static function setElement( &$arr, $name, $value, $overwrite = false ) {
 148                 if ( $arr === null || $name === null || $value === null || !is_array( $arr ) || is_array( $name ) ) {
 149                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 150                 }
 151
 152                 if ( !isset ( $arr[$name] ) || $overwrite ) {
 153                         $arr[$name] = $value;
 154                 } elseif ( is_array( $arr[$name] ) && is_array( $value ) ) {
 155                         $merged = array_intersect_key( $arr[$name], $value );
 156                         if ( !count( $merged ) ) {
 157                                 $arr[$name] += $value;
 158                         } else {
 159                                 ApiBase::dieDebug( __METHOD__, "Attempting to merge element $name" );
 160                         }
 161                 } else {
 162                         ApiBase::dieDebug( __METHOD__, "Attempting to add element $name=$value, existing value is {$arr[$name]}" );
 163                 }
 164         }
 165
 166         /**
 167          * Adds a content element to an array.
 168          * Use this function instead of hardcoding the '*' element.
 169          * @param $arr array to add the content element to
 170          * @param $value Mixed
 171          * @param $subElemName string when present, content element is created
 172          *  as a sub item of $arr. Use this parameter to create elements in
 173          *  format <elem>text</elem> without attributes
 174          */
 175         public static function setContent( &$arr, $value, $subElemName = null ) {
 176                 if ( is_array( $value ) ) {
 177                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 178                 }
 179                 if ( is_null( $subElemName ) ) {
 180                         ApiResult::setElement( $arr, '*', $value );
 181                 } else {
 182                         if ( !isset( $arr[$subElemName] ) ) {
 183                                 $arr[$subElemName] = array();
 184                         }
 185                         ApiResult::setElement( $arr[$subElemName], '*', $value );
 186                 }
 187         }
 188
 189         /**
 190          * In case the array contains indexed values (in addition to named),
 191          * give all indexed values the given tag name. This function MUST be
 192          * called on every array that has numerical indexes.
 193          * @param $arr array
 194          * @param $tag string Tag name
 195          */
 196         public function setIndexedTagName( &$arr, $tag ) {
 197                 // In raw mode, add the '_element', otherwise just ignore
 198                 if ( !$this->getIsRawMode() ) {
 199                         return;
 200                 }
 201                 if ( $arr === null || $tag === null || !is_array( $arr ) || is_array( $tag ) ) {
 202                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 203                 }
 204                 // Do not use setElement() as it is ok to call this more than once
 205                 $arr['_element'] = $tag;
 206         }
 207
 208         /**
 209          * Calls setIndexedTagName() on each sub-array of $arr
 210          * @param $arr array
 211          * @param $tag string Tag name
 212          */
 213         public function setIndexedTagName_recursive( &$arr, $tag ) {
 214                 if ( !is_array( $arr ) ) {
 215                         return;
 216                 }
 217                 foreach ( $arr as &$a ) {
 218                         if ( !is_array( $a ) ) {
 219                                 continue;
 220                         }
 221                         $this->setIndexedTagName( $a, $tag );
 222                         $this->setIndexedTagName_recursive( $a, $tag );
 223                 }
 224         }
 225
 226         /**
 227          * Calls setIndexedTagName() on an array already in the result.
 228          * Don't specify a path to a value that's not in the result, or
 229          * you'll get nasty errors.
 230          * @param $path array Path to the array, like addValue()'s $path
 231          * @param $tag string
 232          */
 233         public function setIndexedTagName_internal( $path, $tag ) {
 234                 $data = &$this->mData;
 235                 foreach ( (array)$path as $p ) {
 236                         if ( !isset( $data[$p] ) ) {
 237                                 $data[$p] = array();
 238                         }
 239                         $data = &$data[$p];
 240                 }
 241                 if ( is_null( $data ) ) {
 242                         return;
 243                 }
 244                 $this->setIndexedTagName( $data, $tag );
 245         }
 246
 247         /**
 248          * Add value to the output data at the given path.
 249          * Path is an indexed array, each element specifying the branch at which to add the new value
 250          * Setting $path to array('a','b','c') is equivalent to data['a']['b']['c'] = $value
 251          * If $name is empty, the $value is added as a next list element data[] = $value
 252          *
 253          * @param $path
 254          * @param $name string
 255          * @param $value mixed
 256          * @param $overwrite bool
 257          *
 258          * @return bool True if $value fits in the result, false if not
 259          */
 260         public function addValue( $path, $name, $value, $overwrite = false ) {
 261                 global $wgAPIMaxResultSize;
 262
 263                 $data = &$this->mData;
 264                 if ( $this->mCheckingSize ) {
 265                         $newsize = $this->mSize + self::size( $value );
 266                         if ( $newsize > $wgAPIMaxResultSize ) {
 267                                 $this->setWarning(
 268                                         "This result was truncated because it would otherwise be larger than the " .
 269                                                         "limit of {$wgAPIMaxResultSize} bytes" );
 270                                 return false;
 271                         }
 272                         $this->mSize = $newsize;
 273                 }
 274
 275                 if ( !is_null( $path ) ) {
 276                         if ( is_array( $path ) ) {
 277                                 foreach ( $path as $p ) {
 278                                         if ( !isset( $data[$p] ) ) {
 279                                                 $data[$p] = array();
 280                                         }
 281                                         $data = &$data[$p];
 282                                 }
 283                         } else {
 284                                 if ( !isset( $data[$path] ) ) {
 285                                         $data[$path] = array();
 286                                 }
 287                                 $data = &$data[$path];
 288                         }
 289                 }
 290
 291                 if ( !$name ) {
 292                         $data[] = $value; // Add list element
 293                 } else {
 294                         self::setElement( $data, $name, $value, $overwrite ); // Add named element
 295                 }
 296                 return true;
 297         }
 298
 299         /**
 300          * Add a parsed limit=max to the result.
 301          *
 302          * @param $moduleName string
 303          * @param $limit int
 304          */
 305         public function setParsedLimit( $moduleName, $limit ) {
 306                 // Add value, allowing overwriting
 307                 $this->addValue( 'limits', $moduleName, $limit, true );
 308         }
 309
 310         /**
 311          * Unset a value previously added to the result set.
 312          * Fails silently if the value isn't found.
 313          * For parameters, see addValue()
 314          * @param $path array
 315          * @param $name string
 316          */
 317         public function unsetValue( $path, $name ) {
 318                 $data = &$this->mData;
 319                 if ( !is_null( $path ) ) {
 320                         foreach ( (array)$path as $p ) {
 321                                 if ( !isset( $data[$p] ) ) {
 322                                         return;
 323                                 }
 324                                 $data = &$data[$p];
 325                         }
 326                 }
 327                 $this->mSize -= self::size( $data[$name] );
 328                 unset( $data[$name] );
 329         }
 330
 331         /**
 332          * Ensure all values in this result are valid UTF-8.
 333          */
 334         public function cleanUpUTF8() {
 335                 array_walk_recursive( $this->mData, array( 'ApiResult', 'cleanUp_helper' ) );
 336         }
 337
 338         /**
 339          * Callback function for cleanUpUTF8()
 340          *
 341          * @param $s string
 342          */
 343         private static function cleanUp_helper( &$s ) {
 344                 if ( !is_string( $s ) ) {
 345                         return;
 346                 }
 347                 global $wgContLang;
 348                 $s = $wgContLang->normalize( $s );
 349         }
 350
 351         /**
 352          * Converts a Status object to an array suitable for addValue
 353          * @param Status $status
 354          * @param string $errorType
 355          * @return array
 356          */
 357         public function convertStatusToArray( $status, $errorType = 'error' ) {
 358                 if ( $status->isGood() ) {
 359                         return array();
 360                 }
 361
 362                 $result = array();
 363                 foreach ( $status->getErrorsByType( $errorType ) as $error ) {
 364                         $this->setIndexedTagName( $error['params'], 'param' );
 365                         $result[] = $error;
 366                 }
 367                 $this->setIndexedTagName( $result, $errorType );
 368                 return $result;
 369         }
 370
 371         public function execute() {
 372                 ApiBase::dieDebug( __METHOD__, 'execute() is not supported on Result object' );
 373         }
 374
 375         public function getVersion() {
 376                 return __CLASS__ . ': $Id$';
 377         }
 378 }