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