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
  30  * array's modifications. As various modules execute, they add different pieces
  31  * of information to this result, 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 outputted 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         /**
  47          * override existing value in addValue() and setElement()
  48          * @since 1.21
  49          */
  50         const OVERRIDE = 1;
  51
  52         /**
  53          * For addValue() and setElement(), if the value does not exist, add it as the first element.
  54          * In case the new value has no name (numerical index), all indexes will be renumbered.
  55          * @since 1.21
  56          */
  57         const ADD_ON_TOP = 2;
  58
  59         private $mData, $mIsRawMode, $mSize, $mCheckingSize;
  60
  61         /**
  62          * Constructor
  63          * @param $main ApiMain object
  64          */
  65         public function __construct( $main ) {
  66                 parent::__construct( $main, 'result' );
  67                 $this->mIsRawMode = false;
  68                 $this->mCheckingSize = true;
  69                 $this->reset();
  70         }
  71
  72         /**
  73          * Clear the current result data.
  74          */
  75         public function reset() {
  76                 $this->mData = array();
  77                 $this->mSize = 0;
  78         }
  79
  80         /**
  81          * Call this function when special elements such as '_element'
  82          * are needed by the formatter, for example in XML printing.
  83          */
  84         public function setRawMode() {
  85                 $this->mIsRawMode = true;
  86         }
  87
  88         /**
  89          * Returns true whether the formatter requested raw data.
  90          * @return bool
  91          */
  92         public function getIsRawMode() {
  93                 return $this->mIsRawMode;
  94         }
  95
  96         /**
  97          * Get the result's internal data array (read-only)
  98          * @return array
  99          */
 100         public function getData() {
 101                 return $this->mData;
 102         }
 103
 104         /**
 105          * Get the 'real' size of a result item. This means the strlen() of the item,
 106          * or the sum of the strlen()s of the elements if the item is an array.
 107          * @param $value mixed
 108          * @return int
 109          */
 110         public static function size( $value ) {
 111                 $s = 0;
 112                 if ( is_array( $value ) ) {
 113                         foreach ( $value as $v ) {
 114                                 $s += self::size( $v );
 115                         }
 116                 } elseif ( !is_object( $value ) ) {
 117                         // Objects can't always be cast to string
 118                         $s = strlen( $value );
 119                 }
 120
 121                 return $s;
 122         }
 123
 124         /**
 125          * Get the size of the result, i.e. the amount of bytes in it
 126          * @return int
 127          */
 128         public function getSize() {
 129                 return $this->mSize;
 130         }
 131
 132         /**
 133          * Disable size checking in addValue(). Don't use this unless you
 134          * REALLY know what you're doing. Values added while size checking
 135          * was disabled will not be counted (ever)
 136          */
 137         public function disableSizeCheck() {
 138                 $this->mCheckingSize = false;
 139         }
 140
 141         /**
 142          * Re-enable size checking in addValue()
 143          */
 144         public function enableSizeCheck() {
 145                 $this->mCheckingSize = true;
 146         }
 147
 148         /**
 149          * Add an output value to the array by name.
 150          * Verifies that value with the same name has not been added before.
 151          * @param array $arr to add $value to
 152          * @param string $name Index of $arr to add $value at
 153          * @param $value mixed
 154          * @param int $flags Zero or more OR-ed flags like OVERRIDE | ADD_ON_TOP.
 155          *    This parameter used to be boolean, and the value of OVERRIDE=1 was
 156          *    specifically chosen so that it would be backwards compatible with the
 157          *    new method signature.
 158          *
 159          * @since 1.21 int $flags replaced boolean $override
 160          */
 161         public static function setElement( &$arr, $name, $value, $flags = 0 ) {
 162                 if ( $arr === null || $name === null || $value === null
 163                         || !is_array( $arr ) || is_array( $name )
 164                 ) {
 165                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 166                 }
 167
 168                 $exists = isset( $arr[$name] );
 169                 if ( !$exists || ( $flags & ApiResult::OVERRIDE ) ) {
 170                         if ( !$exists && ( $flags & ApiResult::ADD_ON_TOP ) ) {
 171                                 $arr = array( $name => $value ) + $arr;
 172                         } else {
 173                                 $arr[$name] = $value;
 174                         }
 175                 } elseif ( is_array( $arr[$name] ) && is_array( $value ) ) {
 176                         $merged = array_intersect_key( $arr[$name], $value );
 177                         if ( !count( $merged ) ) {
 178                                 $arr[$name] += $value;
 179                         } else {
 180                                 ApiBase::dieDebug( __METHOD__, "Attempting to merge element $name" );
 181                         }
 182                 } else {
 183                         ApiBase::dieDebug(
 184                                 __METHOD__,
 185                                 "Attempting to add element $name=$value, existing value is {$arr[$name]}"
 186                         );
 187                 }
 188         }
 189
 190         /**
 191          * Adds a content element to an array.
 192          * Use this function instead of hardcoding the '*' element.
 193          * @param array $arr to add the content element to
 194          * @param $value Mixed
 195          * @param string $subElemName when present, content element is created
 196          *  as a sub item of $arr. Use this parameter to create elements in
 197          *  format "<elem>text</elem>" without attributes.
 198          */
 199         public static function setContent( &$arr, $value, $subElemName = null ) {
 200                 if ( is_array( $value ) ) {
 201                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 202                 }
 203                 if ( is_null( $subElemName ) ) {
 204                         ApiResult::setElement( $arr, '*', $value );
 205                 } else {
 206                         if ( !isset( $arr[$subElemName] ) ) {
 207                                 $arr[$subElemName] = array();
 208                         }
 209                         ApiResult::setElement( $arr[$subElemName], '*', $value );
 210                 }
 211         }
 212
 213         /**
 214          * In case the array contains indexed values (in addition to named),
 215          * give all indexed values the given tag name. This function MUST be
 216          * called on every array that has numerical indexes.
 217          * @param $arr array
 218          * @param string $tag Tag name
 219          */
 220         public function setIndexedTagName( &$arr, $tag ) {
 221                 // In raw mode, add the '_element', otherwise just ignore
 222                 if ( !$this->getIsRawMode() ) {
 223                         return;
 224                 }
 225                 if ( $arr === null || $tag === null || !is_array( $arr ) || is_array( $tag ) ) {
 226                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 227                 }
 228                 // Do not use setElement() as it is ok to call this more than once
 229                 $arr['_element'] = $tag;
 230         }
 231
 232         /**
 233          * Calls setIndexedTagName() on each sub-array of $arr
 234          * @param $arr array
 235          * @param string $tag Tag name
 236          */
 237         public function setIndexedTagName_recursive( &$arr, $tag ) {
 238                 if ( !is_array( $arr ) ) {
 239                         return;
 240                 }
 241                 foreach ( $arr as &$a ) {
 242                         if ( !is_array( $a ) ) {
 243                                 continue;
 244                         }
 245                         $this->setIndexedTagName( $a, $tag );
 246                         $this->setIndexedTagName_recursive( $a, $tag );
 247                 }
 248         }
 249
 250         /**
 251          * Calls setIndexedTagName() on an array already in the result.
 252          * Don't specify a path to a value that's not in the result, or
 253          * you'll get nasty errors.
 254          * @param array $path Path to the array, like addValue()'s $path
 255          * @param $tag string
 256          */
 257         public function setIndexedTagName_internal( $path, $tag ) {
 258                 $data = &$this->mData;
 259                 foreach ( (array)$path as $p ) {
 260                         if ( !isset( $data[$p] ) ) {
 261                                 $data[$p] = array();
 262                         }
 263                         $data = &$data[$p];
 264                 }
 265                 if ( is_null( $data ) ) {
 266                         return;
 267                 }
 268                 $this->setIndexedTagName( $data, $tag );
 269         }
 270
 271         /**
 272          * Add value to the output data at the given path.
 273          * Path can be an indexed array, each element specifying the branch at which to add the new
 274          * value. Setting $path to array('a','b','c') is equivalent to data['a']['b']['c'] = $value.
 275          * If $path is null, the value will be inserted at the data root.
 276          * If $name is empty, the $value is added as a next list element data[] = $value.
 277          *
 278          * @param $path array|string|null
 279          * @param $name string
 280          * @param $value mixed
 281          * @param int $flags Zero or more OR-ed flags like OVERRIDE | ADD_ON_TOP. This
 282          *    parameter used to be boolean, and the value of OVERRIDE=1 was specifically
 283          *    chosen so that it would be backwards compatible with the new method
 284          *    signature.
 285          * @return bool True if $value fits in the result, false if not
 286          *
 287          * @since 1.21 int $flags replaced boolean $override
 288          */
 289         public function addValue( $path, $name, $value, $flags = 0 ) {
 290                 global $wgAPIMaxResultSize;
 291
 292                 $data = &$this->mData;
 293                 if ( $this->mCheckingSize ) {
 294                         $newsize = $this->mSize + self::size( $value );
 295                         if ( $newsize > $wgAPIMaxResultSize ) {
 296                                 $this->setWarning(
 297                                         "This result was truncated because it would otherwise be larger than the " .
 298                                                 "limit of {$wgAPIMaxResultSize} bytes" );
 299
 300                                 return false;
 301                         }
 302                         $this->mSize = $newsize;
 303                 }
 304
 305                 $addOnTop = $flags & ApiResult::ADD_ON_TOP;
 306                 if ( $path !== null ) {
 307                         foreach ( (array)$path as $p ) {
 308                                 if ( !isset( $data[$p] ) ) {
 309                                         if ( $addOnTop ) {
 310                                                 $data = array( $p => array() ) + $data;
 311                                                 $addOnTop = false;
 312                                         } else {
 313                                                 $data[$p] = array();
 314                                         }
 315                                 }
 316                                 $data = &$data[$p];
 317                         }
 318                 }
 319
 320                 if ( !$name ) {
 321                         // Add list element
 322                         if ( $addOnTop ) {
 323                                 // This element needs to be inserted in the beginning
 324                                 // Numerical indexes will be renumbered
 325                                 array_unshift( $data, $value );
 326                         } else {
 327                                 // Add new value at the end
 328                                 $data[] = $value;
 329                         }
 330                 } else {
 331                         // Add named element
 332                         self::setElement( $data, $name, $value, $flags );
 333                 }
 334
 335                 return true;
 336         }
 337
 338         /**
 339          * Add a parsed limit=max to the result.
 340          *
 341          * @param $moduleName string
 342          * @param $limit int
 343          */
 344         public function setParsedLimit( $moduleName, $limit ) {
 345                 // Add value, allowing overwriting
 346                 $this->addValue( 'limits', $moduleName, $limit, ApiResult::OVERRIDE );
 347         }
 348
 349         /**
 350          * Unset a value previously added to the result set.
 351          * Fails silently if the value isn't found.
 352          * For parameters, see addValue()
 353          * @param $path array|null
 354          * @param $name string
 355          */
 356         public function unsetValue( $path, $name ) {
 357                 $data = &$this->mData;
 358                 if ( $path !== null ) {
 359                         foreach ( (array)$path as $p ) {
 360                                 if ( !isset( $data[$p] ) ) {
 361                                         return;
 362                                 }
 363                                 $data = &$data[$p];
 364                         }
 365                 }
 366                 $this->mSize -= self::size( $data[$name] );
 367                 unset( $data[$name] );
 368         }
 369
 370         /**
 371          * Ensure all values in this result are valid UTF-8.
 372          */
 373         public function cleanUpUTF8() {
 374                 array_walk_recursive( $this->mData, array( 'ApiResult', 'cleanUp_helper' ) );
 375         }
 376
 377         /**
 378          * Callback function for cleanUpUTF8()
 379          *
 380          * @param $s string
 381          */
 382         private static function cleanUp_helper( &$s ) {
 383                 if ( !is_string( $s ) ) {
 384                         return;
 385                 }
 386                 global $wgContLang;
 387                 $s = $wgContLang->normalize( $s );
 388         }
 389
 390         /**
 391          * Converts a Status object to an array suitable for addValue
 392          * @param Status $status
 393          * @param string $errorType
 394          * @return array
 395          */
 396         public function convertStatusToArray( $status, $errorType = 'error' ) {
 397                 if ( $status->isGood() ) {
 398                         return array();
 399                 }
 400
 401                 $result = array();
 402                 foreach ( $status->getErrorsByType( $errorType ) as $error ) {
 403                         $this->setIndexedTagName( $error['params'], 'param' );
 404                         $result[] = $error;
 405                 }
 406                 $this->setIndexedTagName( $result, $errorType );
 407
 408                 return $result;
 409         }
 410
 411         public function execute() {
 412                 ApiBase::dieDebug( __METHOD__, 'execute() is not supported on Result object' );
 413         }
 414 }