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