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