includes/api/ApiBase.php

   1 <?php
   2
   3 /*
   4  * Created on Sep 5, 2006
   5  *
   6  * API for MediaWiki 1.8+
   7  *
   8  * Copyright (C) 2006 Yuri Astrakhan <Firstname><Lastname>@gmail.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License along
  21  * with this program; if not, write to the Free Software Foundation, Inc.,
  22  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  * http://www.gnu.org/copyleft/gpl.html
  24  */
  25
  26 /**
  27  * This abstract class implements many basic API functions, and is the base of all API classes.
  28  * The class functions are divided into several areas of functionality:
  29  *
  30  * Module parameters: Derived classes can define getAllowedParams() to specify which parameters to expect,
  31  *      how to parse and validate them.
  32  *
  33  * Profiling: various methods to allow keeping tabs on various tasks and their time costs
  34  *
  35  * Self-documentation: code to allow api to document its own state.
  36  *
  37  * @addtogroup API
  38  */
  39 abstract class ApiBase {
  40
  41         // These constants allow modules to specify exactly how to treat incomming parameters.
  42
  43         const PARAM_DFLT = 0;
  44         const PARAM_ISMULTI = 1;
  45         const PARAM_TYPE = 2;
  46         const PARAM_MAX = 3;
  47         const PARAM_MAX2 = 4;
  48         const PARAM_MIN = 5;
  49
  50         const LIMIT_BIG1 = 500; // Fast query, user's limit
  51         const LIMIT_BIG2 = 5000; // Fast query, bot's limit
  52         const LIMIT_SML1 = 50; // Slow query, user's limit
  53         const LIMIT_SML2 = 500; // Slow query, bot's limit
  54
  55         private $mMainModule, $mModuleName, $mParamPrefix;
  56
  57         /**
  58         * Constructor
  59         */
  60         public function __construct($mainModule, $moduleName, $paramPrefix = '') {
  61                 $this->mMainModule = $mainModule;
  62                 $this->mModuleName = $moduleName;
  63                 $this->mParamPrefix = $paramPrefix;
  64         }
  65
  66         /**
  67          * Executes this module
  68          */
  69         public abstract function execute();
  70
  71         /**
  72          * Get the name of the module being executed by this instance
  73          */
  74         public function getModuleName() {
  75                 return $this->mModuleName;
  76         }
  77
  78         /**
  79          * Get the name of the module as shown in the profiler log
  80          */
  81         public function getModuleProfileName($db = false) {
  82                 if ($db)
  83                         return 'API:' . $this->mModuleName . '-DB';
  84                 else
  85                         return 'API:' . $this->mModuleName;
  86         }
  87
  88         /**
  89          * Get main module
  90          */
  91         public function getMain() {
  92                 return $this->mMainModule;
  93         }
  94
  95         /**
  96          * If this module's $this is the same as $this->mMainModule, its the root, otherwise no
  97          */
  98         public function isMain() {
  99                 return $this === $this->mMainModule;
 100         }
 101
 102         /**
 103          * Get result object
 104          */
 105         public function getResult() {
 106                 // Main module has getResult() method overriden
 107                 // Safety - avoid infinite loop:
 108                 if ($this->isMain())
 109                         ApiBase :: dieDebug(__METHOD__, 'base method was called on main module. ');
 110                 return $this->getMain()->getResult();
 111         }
 112
 113         /**
 114          * Get the result data array
 115          */
 116         public function & getResultData() {
 117                 return $this->getResult()->getData();
 118         }
 119
 120         /**
 121          * If the module may only be used with a certain format module,
 122          * it should override this method to return an instance of that formatter.
 123          * A value of null means the default format will be used.
 124          */
 125         public function getCustomPrinter() {
 126                 return null;
 127         }
 128
 129         /**
 130          * Generates help message for this module, or false if there is no description
 131          */
 132         public function makeHelpMsg() {
 133
 134                 static $lnPrfx = "\n  ";
 135
 136                 $msg = $this->getDescription();
 137
 138                 if ($msg !== false) {
 139
 140                         if (!is_array($msg))
 141                                 $msg = array (
 142                                         $msg
 143                                 );
 144                         $msg = $lnPrfx . implode($lnPrfx, $msg) . "\n";
 145
 146                         // Parameters
 147                         $paramsMsg = $this->makeHelpMsgParameters();
 148                         if ($paramsMsg !== false) {
 149                                 $msg .= "Parameters:\n$paramsMsg";
 150                         }
 151
 152                         // Examples
 153                         $examples = $this->getExamples();
 154                         if ($examples !== false) {
 155                                 if (!is_array($examples))
 156                                         $examples = array (
 157                                                 $examples
 158                                         );
 159                                 $msg .= 'Example' . (count($examples) > 1 ? 's' : '') . ":\n  ";
 160                                 $msg .= implode($lnPrfx, $examples) . "\n";
 161                         }
 162
 163                         if ($this->getMain()->getShowVersions()) {
 164                                 $versions = $this->getVersion();
 165                                 $pattern = '(\$.*) ([0-9a-z_]+\.php) (.*\$)';
 166                                 $replacement = '\\0' . "\n    " . 'http://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/includes/api/\\2';
 167
 168                                 if (is_array($versions)) {
 169                                         foreach ($versions as &$v)
 170                                                 $v = eregi_replace($pattern, $replacement, $v);
 171                                         $versions = implode("\n  ", $versions);
 172                                 }
 173                                 else
 174                                         $versions = eregi_replace($pattern, $replacement, $versions);
 175
 176                                 $msg .= "Version:\n  $versions\n";
 177                         }
 178                 }
 179
 180                 return $msg;
 181         }
 182
 183         public function makeHelpMsgParameters() {
 184                 $params = $this->getAllowedParams();
 185                 if ($params !== false) {
 186
 187                         $paramsDescription = $this->getParamDescription();
 188                         $msg = '';
 189                         $paramPrefix = "\n" . str_repeat(' ', 19);
 190                         foreach ($params as $paramName => $paramSettings) {
 191                                 $desc = isset ($paramsDescription[$paramName]) ? $paramsDescription[$paramName] : '';
 192                                 if (is_array($desc))
 193                                         $desc = implode($paramPrefix, $desc);
 194
 195                                 @ $type = $paramSettings[self :: PARAM_TYPE];
 196                                 if (isset ($type)) {
 197                                         if (isset ($paramSettings[self :: PARAM_ISMULTI]))
 198                                                 $prompt = 'Values (separate with \'|\'): ';
 199                                         else
 200                                                 $prompt = 'One value: ';
 201
 202                                         if (is_array($type)) {
 203                                                 $choices = array();
 204                                                 $nothingPrompt = false;
 205                                                 foreach ($type as $t)
 206                                                         if ($t=='')
 207                                                                 $nothingPrompt = 'Can be empty, or ';
 208                                                         else
 209                                                                 $choices[] =  $t;
 210                                                 $desc .= $paramPrefix . $nothingPrompt . $prompt . implode(', ', $choices);
 211                                         } else {
 212                                                 switch ($type) {
 213                                                         case 'namespace':
 214                                                                 // Special handling because namespaces are type-limited, yet they are not given
 215                                                                 $desc .= $paramPrefix . $prompt . implode(', ', ApiBase :: getValidNamespaces());
 216                                                                 break;
 217                                                         case 'limit':
 218                                                                 $desc .= $paramPrefix . "No more than {$paramSettings[self :: PARAM_MAX]} ({$paramSettings[self :: PARAM_MAX2]} for bots) allowed.";
 219                                                                 break;
 220                                                         case 'integer':
 221                                                                 $hasMin = isset($paramSettings[self :: PARAM_MIN]);
 222                                                                 $hasMax = isset($paramSettings[self :: PARAM_MAX]);
 223                                                                 if ($hasMin || $hasMax) {
 224                                                                         if (!$hasMax)
 225                                                                                 $intRangeStr = "The value must be no less than {$paramSettings[self :: PARAM_MIN]}";
 226                                                                         elseif (!$hasMin)
 227                                                                                 $intRangeStr = "The value must be no more than {$paramSettings[self :: PARAM_MAX]}";
 228                                                                         else
 229                                                                                 $intRangeStr = "The value must be between {$paramSettings[self :: PARAM_MIN]} and {$paramSettings[self :: PARAM_MAX]}";
 230
 231                                                                         $desc .= $paramPrefix . $intRangeStr;
 232                                                                 }
 233                                                                 break;
 234                                                 }
 235                                         }
 236                                 }
 237
 238                                 $default = is_array($paramSettings) ? (isset ($paramSettings[self :: PARAM_DFLT]) ? $paramSettings[self :: PARAM_DFLT] : null) : $paramSettings;
 239                                 if (!is_null($default) && $default !== false)
 240                                         $desc .= $paramPrefix . "Default: $default";
 241
 242                                 $msg .= sprintf("  %-14s - %s\n", $this->encodeParamName($paramName), $desc);
 243                         }
 244                         return $msg;
 245
 246                 } else
 247                         return false;
 248         }
 249
 250         /**
 251          * Returns the description string for this module
 252          */
 253         protected function getDescription() {
 254                 return false;
 255         }
 256
 257         /**
 258          * Returns usage examples for this module. Return null if no examples are available.
 259          */
 260         protected function getExamples() {
 261                 return false;
 262         }
 263
 264         /**
 265          * Returns an array of allowed parameters (keys) => default value for that parameter
 266          */
 267         protected function getAllowedParams() {
 268                 return false;
 269         }
 270
 271         /**
 272          * Returns the description string for the given parameter.
 273          */
 274         protected function getParamDescription() {
 275                 return false;
 276         }
 277
 278         /**
 279          * This method mangles parameter name based on the prefix supplied to the constructor.
 280          * Override this method to change parameter name during runtime
 281          */
 282         public function encodeParamName($paramName) {
 283                 return $this->mParamPrefix . $paramName;
 284         }
 285
 286         /**
 287         * Using getAllowedParams(), makes an array of the values provided by the user,
 288         * with key being the name of the variable, and value - validated value from user or default.
 289         * This method can be used to generate local variables using extract().
 290         */
 291         public function extractRequestParams() {
 292                 $params = $this->getAllowedParams();
 293                 $results = array ();
 294
 295                 foreach ($params as $paramName => $paramSettings)
 296                         $results[$paramName] = $this->getParameterFromSettings($paramName, $paramSettings);
 297
 298                 return $results;
 299         }
 300
 301         /**
 302          * Get a value for the given parameter
 303          */
 304         protected function getParameter($paramName) {
 305                 $params = $this->getAllowedParams();
 306                 $paramSettings = $params[$paramName];
 307                 return $this->getParameterFromSettings($paramName, $paramSettings);
 308         }
 309
 310         public static function getValidNamespaces() {
 311                 static $mValidNamespaces = null;
 312                 if (is_null($mValidNamespaces)) {
 313
 314                         global $wgContLang;
 315                         $mValidNamespaces = array ();
 316                         foreach (array_keys($wgContLang->getNamespaces()) as $ns) {
 317                                 if ($ns >= 0)
 318                                         $mValidNamespaces[] = $ns;
 319                         }
 320                 }
 321                 return $mValidNamespaces;
 322         }
 323
 324         /**
 325          * Using the settings determine the value for the given parameter
 326          * @param $paramName String: parameter name
 327          * @param $paramSettings Mixed: default value or an array of settings using PARAM_* constants.
 328          */
 329         protected function getParameterFromSettings($paramName, $paramSettings) {
 330
 331                 // Some classes may decide to change parameter names
 332                 $paramName = $this->encodeParamName($paramName);
 333
 334                 if (!is_array($paramSettings)) {
 335                         $default = $paramSettings;
 336                         $multi = false;
 337                         $type = gettype($paramSettings);
 338                 } else {
 339                         $default = isset ($paramSettings[self :: PARAM_DFLT]) ? $paramSettings[self :: PARAM_DFLT] : null;
 340                         $multi = isset ($paramSettings[self :: PARAM_ISMULTI]) ? $paramSettings[self :: PARAM_ISMULTI] : false;
 341                         $type = isset ($paramSettings[self :: PARAM_TYPE]) ? $paramSettings[self :: PARAM_TYPE] : null;
 342
 343                         // When type is not given, and no choices, the type is the same as $default
 344                         if (!isset ($type)) {
 345                                 if (isset ($default))
 346                                         $type = gettype($default);
 347                                 else
 348                                         $type = 'NULL'; // allow everything
 349                         }
 350                 }
 351
 352                 if ($type == 'boolean') {
 353                         if (isset ($default) && $default !== false) {
 354                                 // Having a default value of anything other than 'false' is pointless
 355                                 ApiBase :: dieDebug(__METHOD__, "Boolean param $paramName's default is set to '$default'");
 356                         }
 357
 358                         $value = $this->getMain()->getRequest()->getCheck($paramName);
 359                 } else {
 360                         $value = $this->getMain()->getRequest()->getVal($paramName, $default);
 361
 362                         if (isset ($value) && $type == 'namespace')
 363                                 $type = ApiBase :: getValidNamespaces();
 364                 }
 365
 366                 if (isset ($value) && ($multi || is_array($type)))
 367                         $value = $this->parseMultiValue($paramName, $value, $multi, is_array($type) ? $type : null);
 368
 369                 // More validation only when choices were not given
 370                 // choices were validated in parseMultiValue()
 371                 if (isset ($value)) {
 372                         if (!is_array($type)) {
 373                                 switch ($type) {
 374                                         case 'NULL' : // nothing to do
 375                                                 break;
 376                                         case 'string' : // nothing to do
 377                                                 break;
 378                                         case 'integer' : // Force everything using intval() and optionally validate limits
 379
 380                                                 $value = is_array($value) ? array_map('intval', $value) : intval($value);
 381                                                 $checkMin = isset ($paramSettings[self :: PARAM_MIN]);
 382                                                 $checkMax = isset ($paramSettings[self :: PARAM_MAX]);
 383
 384                                                 if ($checkMin || $checkMax) {
 385                                                         $min = $checkMin ? $paramSettings[self :: PARAM_MIN] : false;
 386                                                         $max = $checkMax ? $paramSettings[self :: PARAM_MAX] : false;
 387
 388                                                         $values = is_array($value) ? $value : array($value);
 389                                                         foreach ($values as $v) {
 390                                                                 if ($checkMin && $v < $min)
 391                                                                         $this->dieUsage("$paramName may not be less than $min (set to $v)", $paramName);
 392                                                                 if ($checkMax && $v > $max)
 393                                                                         $this->dieUsage("$paramName may not be over $max (set to $v)", $paramName);
 394                                                         }
 395                                                 }
 396                                                 break;
 397                                         case 'limit' :
 398                                                 if (!isset ($paramSettings[self :: PARAM_MAX]) || !isset ($paramSettings[self :: PARAM_MAX2]))
 399                                                         ApiBase :: dieDebug(__METHOD__, "MAX1 or MAX2 are not defined for the limit $paramName");
 400                                                 if ($multi)
 401                                                         ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
 402                                                 $min = isset ($paramSettings[self :: PARAM_MIN]) ? $paramSettings[self :: PARAM_MIN] : 0;
 403                                                 $value = intval($value);
 404                                                 $this->validateLimit($paramName, $value, $min, $paramSettings[self :: PARAM_MAX], $paramSettings[self :: PARAM_MAX2]);
 405                                                 break;
 406                                         case 'boolean' :
 407                                                 if ($multi)
 408                                                         ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
 409                                                 break;
 410                                         case 'timestamp' :
 411                                                 if ($multi)
 412                                                         ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
 413                                                 $value = wfTimestamp(TS_UNIX, $value);
 414                                                 if ($value === 0)
 415                                                         $this->dieUsage("Invalid value '$value' for timestamp parameter $paramName", "badtimestamp_{$paramName}");
 416                                                 $value = wfTimestamp(TS_MW, $value);
 417                                                 break;
 418                                         case 'user' :
 419                                                 $title = Title::makeTitleSafe( NS_USER, $value );
 420                                                 if ( is_null( $title ) )
 421                                                         $this->dieUsage("Invalid value $user for user parameter $paramName", "baduser_{$paramName}");
 422                                                 $value = $title->getText();
 423                                                 break;
 424                                         default :
 425                                                 ApiBase :: dieDebug(__METHOD__, "Param $paramName's type is unknown - $type");
 426                                 }
 427                         }
 428
 429                         // There should never be any duplicate values in a list
 430                         if (is_array($value))
 431                                 $value = array_unique($value);
 432                 }
 433
 434                 return $value;
 435         }
 436
 437         /**
 438         * Return an array of values that were given in a 'a|b|c' notation,
 439         * after it optionally validates them against the list allowed values.
 440         *
 441         * @param valueName - The name of the parameter (for error reporting)
 442         * @param value - The value being parsed
 443         * @param allowMultiple - Can $value contain more than one value separated by '|'?
 444         * @param allowedValues - An array of values to check against. If null, all values are accepted.
 445         * @return (allowMultiple ? an_array_of_values : a_single_value)
 446         */
 447         protected function parseMultiValue($valueName, $value, $allowMultiple, $allowedValues) {
 448                 $valuesList = explode('|', $value);
 449                 if (!$allowMultiple && count($valuesList) != 1) {
 450                         $possibleValues = is_array($allowedValues) ? "of '" . implode("', '", $allowedValues) . "'" : '';
 451                         $this->dieUsage("Only one $possibleValues is allowed for parameter '$valueName'", "multival_$valueName");
 452                 }
 453                 if (is_array($allowedValues)) {
 454                         $unknownValues = array_diff($valuesList, $allowedValues);
 455                         if ($unknownValues) {
 456                                 $this->dieUsage('Unrecognised value' . (count($unknownValues) > 1 ? "s" : "") . " for parameter '$valueName'", "unknown_$valueName");
 457                         }
 458                 }
 459
 460                 return $allowMultiple ? $valuesList : $valuesList[0];
 461         }
 462
 463         /**
 464         * Validate the value against the minimum and user/bot maximum limits. Prints usage info on failure.
 465         */
 466         function validateLimit($varname, $value, $min, $max, $botMax) {
 467                 if ($value < $min) {
 468                         $this->dieUsage("$varname may not be less than $min (set to $value)", $varname);
 469                 }
 470
 471                 if ($this->getMain()->isBot()) {
 472                         if ($value > $botMax) {
 473                                 $this->dieUsage("$varname may not be over $botMax (set to $value) for bots", $varname);
 474                         }
 475                 }
 476                 elseif ($value > $max) {
 477                         $this->dieUsage("$varname may not be over $max (set to $value) for users", $varname);
 478                 }
 479         }
 480
 481         /**
 482          * Call main module's error handler
 483          */
 484         public function dieUsage($description, $errorCode, $httpRespCode = 0) {
 485                 throw new UsageException($description, $this->encodeParamName($errorCode), $httpRespCode);
 486         }
 487
 488         /**
 489          * Internal code errors should be reported with this method
 490          */
 491         protected static function dieDebug($method, $message) {
 492                 wfDebugDieBacktrace("Internal error in $method: $message");
 493         }
 494
 495         /**
 496          * Profiling: total module execution time
 497          */
 498         private $mTimeIn = 0, $mModuleTime = 0;
 499
 500         /**
 501          * Start module profiling
 502          */
 503         public function profileIn() {
 504                 if ($this->mTimeIn !== 0)
 505                         ApiBase :: dieDebug(__METHOD__, 'called twice without calling profileOut()');
 506                 $this->mTimeIn = microtime(true);
 507                 wfProfileIn($this->getModuleProfileName());
 508         }
 509
 510         /**
 511          * End module profiling
 512          */
 513         public function profileOut() {
 514                 if ($this->mTimeIn === 0)
 515                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileIn() first');
 516                 if ($this->mDBTimeIn !== 0)
 517                         ApiBase :: dieDebug(__METHOD__, 'must be called after database profiling is done with profileDBOut()');
 518
 519                 $this->mModuleTime += microtime(true) - $this->mTimeIn;
 520                 $this->mTimeIn = 0;
 521                 wfProfileOut($this->getModuleProfileName());
 522         }
 523
 524         /**
 525          * When modules crash, sometimes it is needed to do a profileOut() regardless
 526          * of the profiling state the module was in. This method does such cleanup.
 527          */
 528         public function safeProfileOut() {
 529                 if ($this->mTimeIn !== 0) {
 530                         if ($this->mDBTimeIn !== 0)
 531                                 $this->profileDBOut();
 532                         $this->profileOut();
 533                 }
 534         }
 535
 536         /**
 537          * Total time the module was executed
 538          */
 539         public function getProfileTime() {
 540                 if ($this->mTimeIn !== 0)
 541                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileOut() first');
 542                 return $this->mModuleTime;
 543         }
 544
 545         /**
 546          * Profiling: database execution time
 547          */
 548         private $mDBTimeIn = 0, $mDBTime = 0;
 549
 550         /**
 551          * Start module profiling
 552          */
 553         public function profileDBIn() {
 554                 if ($this->mTimeIn === 0)
 555                         ApiBase :: dieDebug(__METHOD__, 'must be called while profiling the entire module with profileIn()');
 556                 if ($this->mDBTimeIn !== 0)
 557                         ApiBase :: dieDebug(__METHOD__, 'called twice without calling profileDBOut()');
 558                 $this->mDBTimeIn = microtime(true);
 559                 wfProfileIn($this->getModuleProfileName(true));
 560         }
 561
 562         /**
 563          * End database profiling
 564          */
 565         public function profileDBOut() {
 566                 if ($this->mTimeIn === 0)
 567                         ApiBase :: dieDebug(__METHOD__, 'must be called while profiling the entire module with profileIn()');
 568                 if ($this->mDBTimeIn === 0)
 569                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileDBIn() first');
 570
 571                 $time = microtime(true) - $this->mDBTimeIn;
 572                 $this->mDBTimeIn = 0;
 573
 574                 $this->mDBTime += $time;
 575                 $this->getMain()->mDBTime += $time;
 576                 wfProfileOut($this->getModuleProfileName(true));
 577         }
 578
 579         /**
 580          * Total time the module used the database
 581          */
 582         public function getProfileDBTime() {
 583                 if ($this->mDBTimeIn !== 0)
 584                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileDBOut() first');
 585                 return $this->mDBTime;
 586         }
 587
 588         public static function debugPrint($value, $name = 'unknown', $backtrace = false) {
 589                 print "\n\n<pre><b>Debuging value '$name':</b>\n\n";
 590                 var_export($value);
 591                 if ($backtrace)
 592                         print "\n" . wfBacktrace();
 593                 print "\n</pre>\n";
 594         }
 595
 596         public abstract function getVersion();
 597
 598         public static function getBaseVersion() {
 599                 return __CLASS__ . ': $Id$';
 600         }
 601 }
 602 ?>