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 three 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  *   '_subelements' This key causes the specified elements to be returned as subelements rather than attributes.
  40  *                  It is only inserted if the formatter returned true for getNeedsRawData()
  41  *   '*'            This key has special meaning only to the XML formatter, and is outputted as is
  42  *                  for all others. In XML it becomes the content of the current element.
  43  *
  44  * @ingroup API
  45  */
  46 class ApiResult extends ApiBase {
  47
  48         /**
  49          * override existing value in addValue() and setElement()
  50          * @since 1.21
  51          */
  52         const OVERRIDE = 1;
  53
  54         /**
  55          * For addValue() and setElement(), if the value does not exist, add it as the first element.
  56          * In case the new value has no name (numerical index), all indexes will be renumbered.
  57          * @since 1.21
  58          */
  59         const ADD_ON_TOP = 2;
  60
  61         private $mData, $mIsRawMode, $mSize, $mCheckingSize;
  62
  63         /**
  64          * @param ApiMain $main
  65          */
  66         public function __construct( ApiMain $main ) {
  67                 parent::__construct( $main, 'result' );
  68                 $this->mIsRawMode = false;
  69                 $this->mCheckingSize = true;
  70                 $this->reset();
  71         }
  72
  73         /**
  74          * Clear the current result data.
  75          */
  76         public function reset() {
  77                 $this->mData = array();
  78                 $this->mSize = 0;
  79         }
  80
  81         /**
  82          * Call this function when special elements such as '_element'
  83          * are needed by the formatter, for example in XML printing.
  84          * @since 1.23 $flag parameter added
  85          * @param bool $flag Set the raw mode flag to this state
  86          */
  87         public function setRawMode( $flag = true ) {
  88                 $this->mIsRawMode = $flag;
  89         }
  90
  91         /**
  92          * Returns true whether the formatter requested raw data.
  93          * @return bool
  94          */
  95         public function getIsRawMode() {
  96                 return $this->mIsRawMode;
  97         }
  98
  99         /**
 100          * Get the result's internal data array (read-only)
 101          * @return array
 102          */
 103         public function getData() {
 104                 return $this->mData;
 105         }
 106
 107         /**
 108          * Get the 'real' size of a result item. This means the strlen() of the item,
 109          * or the sum of the strlen()s of the elements if the item is an array.
 110          * @param mixed $value
 111          * @return int
 112          */
 113         public static function size( $value ) {
 114                 $s = 0;
 115                 if ( is_array( $value ) ) {
 116                         foreach ( $value as $v ) {
 117                                 $s += self::size( $v );
 118                         }
 119                 } elseif ( !is_object( $value ) ) {
 120                         // Objects can't always be cast to string
 121                         $s = strlen( $value );
 122                 }
 123
 124                 return $s;
 125         }
 126
 127         /**
 128          * Get the size of the result, i.e. the amount of bytes in it
 129          * @return int
 130          */
 131         public function getSize() {
 132                 return $this->mSize;
 133         }
 134
 135         /**
 136          * Disable size checking in addValue(). Don't use this unless you
 137          * REALLY know what you're doing. Values added while size checking
 138          * was disabled will not be counted (ever)
 139          */
 140         public function disableSizeCheck() {
 141                 $this->mCheckingSize = false;
 142         }
 143
 144         /**
 145          * Re-enable size checking in addValue()
 146          */
 147         public function enableSizeCheck() {
 148                 $this->mCheckingSize = true;
 149         }
 150
 151         /**
 152          * Add an output value to the array by name.
 153          * Verifies that value with the same name has not been added before.
 154          * @param array $arr To add $value to
 155          * @param string $name Index of $arr to add $value at
 156          * @param mixed $value
 157          * @param int $flags Zero or more OR-ed flags like OVERRIDE | ADD_ON_TOP.
 158          *    This parameter used to be boolean, and the value of OVERRIDE=1 was
 159          *    specifically chosen so that it would be backwards compatible with the
 160          *    new method signature.
 161          *
 162          * @since 1.21 int $flags replaced boolean $override
 163          */
 164         public static function setElement( &$arr, $name, $value, $flags = 0 ) {
 165                 if ( $arr === null || $name === null || $value === null
 166                         || !is_array( $arr ) || is_array( $name )
 167                 ) {
 168                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 169                 }
 170
 171                 $exists = isset( $arr[$name] );
 172                 if ( !$exists || ( $flags & ApiResult::OVERRIDE ) ) {
 173                         if ( !$exists && ( $flags & ApiResult::ADD_ON_TOP ) ) {
 174                                 $arr = array( $name => $value ) + $arr;
 175                         } else {
 176                                 $arr[$name] = $value;
 177                         }
 178                 } elseif ( is_array( $arr[$name] ) && is_array( $value ) ) {
 179                         $merged = array_intersect_key( $arr[$name], $value );
 180                         if ( !count( $merged ) ) {
 181                                 $arr[$name] += $value;
 182                         } else {
 183                                 ApiBase::dieDebug( __METHOD__, "Attempting to merge element $name" );
 184                         }
 185                 } else {
 186                         ApiBase::dieDebug(
 187                                 __METHOD__,
 188                                 "Attempting to add element $name=$value, existing value is {$arr[$name]}"
 189                         );
 190                 }
 191         }
 192
 193         /**
 194          * Adds a content element to an array.
 195          * Use this function instead of hardcoding the '*' element.
 196          * @param array $arr To add the content element to
 197          * @param mixed $value
 198          * @param string $subElemName When present, content element is created
 199          *  as a sub item of $arr. Use this parameter to create elements in
 200          *  format "<elem>text</elem>" without attributes.
 201          */
 202         public static function setContent( &$arr, $value, $subElemName = null ) {
 203                 if ( is_array( $value ) ) {
 204                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 205                 }
 206                 if ( is_null( $subElemName ) ) {
 207                         ApiResult::setElement( $arr, '*', $value );
 208                 } else {
 209                         if ( !isset( $arr[$subElemName] ) ) {
 210                                 $arr[$subElemName] = array();
 211                         }
 212                         ApiResult::setElement( $arr[$subElemName], '*', $value );
 213                 }
 214         }
 215
 216         /**
 217          * Causes the elements with the specified names to be output as
 218          * subelements rather than attributes.
 219          * @param array $arr
 220          * @param array|string $names The element name(s) to be output as subelements
 221          */
 222         public function setSubelements( &$arr, $names ) {
 223                 // In raw mode, add the '_subelements', otherwise just ignore
 224                 if ( !$this->getIsRawMode() ) {
 225                         return;
 226                 }
 227                 if ( $arr === null || $names === null || !is_array( $arr ) ) {
 228                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 229                 }
 230                 if ( !is_array( $names ) ) {
 231                         $names = array( $names );
 232                 }
 233                 if ( !isset( $arr['_subelements'] ) ) {
 234                         $arr['_subelements'] = $names;
 235                 } else {
 236                         $arr['_subelements'] = array_merge( $arr['_subelements'], $names );
 237                 }
 238         }
 239
 240         /**
 241          * In case the array contains indexed values (in addition to named),
 242          * give all indexed values the given tag name. This function MUST be
 243          * called on every array that has numerical indexes.
 244          * @param array $arr
 245          * @param string $tag Tag name
 246          */
 247         public function setIndexedTagName( &$arr, $tag ) {
 248                 // In raw mode, add the '_element', otherwise just ignore
 249                 if ( !$this->getIsRawMode() ) {
 250                         return;
 251                 }
 252                 if ( $arr === null || $tag === null || !is_array( $arr ) || is_array( $tag ) ) {
 253                         ApiBase::dieDebug( __METHOD__, 'Bad parameter' );
 254                 }
 255                 // Do not use setElement() as it is ok to call this more than once
 256                 $arr['_element'] = $tag;
 257         }
 258
 259         /**
 260          * Calls setIndexedTagName() on each sub-array of $arr
 261          * @param array $arr
 262          * @param string $tag Tag name
 263          */
 264         public function setIndexedTagName_recursive( &$arr, $tag ) {
 265                 if ( !is_array( $arr ) ) {
 266                         return;
 267                 }
 268                 foreach ( $arr as &$a ) {
 269                         if ( !is_array( $a ) ) {
 270                                 continue;
 271                         }
 272                         $this->setIndexedTagName( $a, $tag );
 273                         $this->setIndexedTagName_recursive( $a, $tag );
 274                 }
 275         }
 276
 277         /**
 278          * Calls setIndexedTagName() on an array already in the result.
 279          * Don't specify a path to a value that's not in the result, or
 280          * you'll get nasty errors.
 281          * @param array $path Path to the array, like addValue()'s $path
 282          * @param string $tag
 283          */
 284         public function setIndexedTagName_internal( $path, $tag ) {
 285                 $data = &$this->mData;
 286                 foreach ( (array)$path as $p ) {
 287                         if ( !isset( $data[$p] ) ) {
 288                                 $data[$p] = array();
 289                         }
 290                         $data = &$data[$p];
 291                 }
 292                 if ( is_null( $data ) ) {
 293                         return;
 294                 }
 295                 $this->setIndexedTagName( $data, $tag );
 296         }
 297
 298         /**
 299          * Add value to the output data at the given path.
 300          * Path can be an indexed array, each element specifying the branch at which to add the new
 301          * value. Setting $path to array('a','b','c') is equivalent to data['a']['b']['c'] = $value.
 302          * If $path is null, the value will be inserted at the data root.
 303          * If $name is empty, the $value is added as a next list element data[] = $value.
 304          *
 305          * @param array|string|null $path
 306          * @param string $name
 307          * @param mixed $value
 308          * @param int $flags Zero or more OR-ed flags like OVERRIDE | ADD_ON_TOP. This
 309          *    parameter used to be boolean, and the value of OVERRIDE=1 was specifically
 310          *    chosen so that it would be backwards compatible with the new method
 311          *    signature.
 312          * @return bool True if $value fits in the result, false if not
 313          *
 314          * @since 1.21 int $flags replaced boolean $override
 315          */
 316         public function addValue( $path, $name, $value, $flags = 0 ) {
 317                 $data = &$this->mData;
 318                 if ( $this->mCheckingSize ) {
 319                         $newsize = $this->mSize + self::size( $value );
 320                         $maxResultSize = $this->getConfig()->get( 'APIMaxResultSize' );
 321                         if ( $newsize > $maxResultSize ) {
 322                                 $this->setWarning(
 323                                         "This result was truncated because it would otherwise be larger than the " .
 324                                                 "limit of {$maxResultSize} bytes" );
 325
 326                                 return false;
 327                         }
 328                         $this->mSize = $newsize;
 329                 }
 330
 331                 $addOnTop = $flags & ApiResult::ADD_ON_TOP;
 332                 if ( $path !== null ) {
 333                         foreach ( (array)$path as $p ) {
 334                                 if ( !isset( $data[$p] ) ) {
 335                                         if ( $addOnTop ) {
 336                                                 $data = array( $p => array() ) + $data;
 337                                                 $addOnTop = false;
 338                                         } else {
 339                                                 $data[$p] = array();
 340                                         }
 341                                 }
 342                                 $data = &$data[$p];
 343                         }
 344                 }
 345
 346                 if ( !$name ) {
 347                         // Add list element
 348                         if ( $addOnTop ) {
 349                                 // This element needs to be inserted in the beginning
 350                                 // Numerical indexes will be renumbered
 351                                 array_unshift( $data, $value );
 352                         } else {
 353                                 // Add new value at the end
 354                                 $data[] = $value;
 355                         }
 356                 } else {
 357                         // Add named element
 358                         self::setElement( $data, $name, $value, $flags );
 359                 }
 360
 361                 return true;
 362         }
 363
 364         /**
 365          * Add a parsed limit=max to the result.
 366          *
 367          * @param string $moduleName
 368          * @param int $limit
 369          */
 370         public function setParsedLimit( $moduleName, $limit ) {
 371                 // Add value, allowing overwriting
 372                 $this->addValue( 'limits', $moduleName, $limit, ApiResult::OVERRIDE );
 373         }
 374
 375         /**
 376          * Unset a value previously added to the result set.
 377          * Fails silently if the value isn't found.
 378          * For parameters, see addValue()
 379          * @param array|null $path
 380          * @param string $name
 381          */
 382         public function unsetValue( $path, $name ) {
 383                 $data = &$this->mData;
 384                 if ( $path !== null ) {
 385                         foreach ( (array)$path as $p ) {
 386                                 if ( !isset( $data[$p] ) ) {
 387                                         return;
 388                                 }
 389                                 $data = &$data[$p];
 390                         }
 391                 }
 392                 $this->mSize -= self::size( $data[$name] );
 393                 unset( $data[$name] );
 394         }
 395
 396         /**
 397          * Ensure all values in this result are valid UTF-8.
 398          */
 399         public function cleanUpUTF8() {
 400                 array_walk_recursive( $this->mData, array( 'ApiResult', 'cleanUp_helper' ) );
 401         }
 402
 403         /**
 404          * Callback function for cleanUpUTF8()
 405          *
 406          * @param string $s
 407          */
 408         private static function cleanUp_helper( &$s ) {
 409                 if ( !is_string( $s ) ) {
 410                         return;
 411                 }
 412                 global $wgContLang;
 413                 $s = $wgContLang->normalize( $s );
 414         }
 415
 416         /**
 417          * Converts a Status object to an array suitable for addValue
 418          * @param Status $status
 419          * @param string $errorType
 420          * @return array
 421          */
 422         public function convertStatusToArray( $status, $errorType = 'error' ) {
 423                 if ( $status->isGood() ) {
 424                         return array();
 425                 }
 426
 427                 $result = array();
 428                 foreach ( $status->getErrorsByType( $errorType ) as $error ) {
 429                         $this->setIndexedTagName( $error['params'], 'param' );
 430                         $result[] = $error;
 431                 }
 432                 $this->setIndexedTagName( $result, $errorType );
 433
 434                 return $result;
 435         }
 436
 437         public function execute() {
 438                 ApiBase::dieDebug( __METHOD__, 'execute() is not supported on Result object' );
 439         }
 440 }