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