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, std user limit
  51         const LIMIT_BIG2 = 5000; // Fast query, bot/sysop limit
  52         const LIMIT_SML1 = 50; // Slow query, std user limit
  53         const LIMIT_SML2 = 500; // Slow query, bot/sysop 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 parameter prefix (usually two letters or an empty string).
  80          */
  81         public function getParamPrefix() {
  82                 return $this->mParamPrefix;
  83         }
  84
  85         /**
  86          * Get the name of the module as shown in the profiler log
  87          */
  88         public function getModuleProfileName($db = false) {
  89                 if ($db)
  90                         return 'API:' . $this->mModuleName . '-DB';
  91                 else
  92                         return 'API:' . $this->mModuleName;
  93         }
  94
  95         /**
  96          * Get main module
  97          */
  98         public function getMain() {
  99                 return $this->mMainModule;
 100         }
 101
 102         /**
 103          * If this module's $this is the same as $this->mMainModule, its the root, otherwise no
 104          */
 105         public function isMain() {
 106                 return $this === $this->mMainModule;
 107         }
 108
 109         /**
 110          * Get result object
 111          */
 112         public function getResult() {
 113                 // Main module has getResult() method overriden
 114                 // Safety - avoid infinite loop:
 115                 if ($this->isMain())
 116                         ApiBase :: dieDebug(__METHOD__, 'base method was called on main module. ');
 117                 return $this->getMain()->getResult();
 118         }
 119
 120         /**
 121          * Get the result data array
 122          */
 123         public function & getResultData() {
 124                 return $this->getResult()->getData();
 125         }
 126
 127         /**
 128          * If the module may only be used with a certain format module,
 129          * it should override this method to return an instance of that formatter.
 130          * A value of null means the default format will be used.
 131          */
 132         public function getCustomPrinter() {
 133                 return null;
 134         }
 135
 136         /**
 137          * Generates help message for this module, or false if there is no description
 138          */
 139         public function makeHelpMsg() {
 140
 141                 static $lnPrfx = "\n  ";
 142
 143                 $msg = $this->getDescription();
 144
 145                 if ($msg !== false) {
 146
 147                         if (!is_array($msg))
 148                                 $msg = array (
 149                                         $msg
 150                                 );
 151                         $msg = $lnPrfx . implode($lnPrfx, $msg) . "\n";
 152
 153                         // Parameters
 154                         $paramsMsg = $this->makeHelpMsgParameters();
 155                         if ($paramsMsg !== false) {
 156                                 $msg .= "Parameters:\n$paramsMsg";
 157                         }
 158
 159                         // Examples
 160                         $examples = $this->getExamples();
 161                         if ($examples !== false) {
 162                                 if (!is_array($examples))
 163                                         $examples = array (
 164                                                 $examples
 165                                         );
 166                                 $msg .= 'Example' . (count($examples) > 1 ? 's' : '') . ":\n  ";
 167                                 $msg .= implode($lnPrfx, $examples) . "\n";
 168                         }
 169
 170                         if ($this->getMain()->getShowVersions()) {
 171                                 $versions = $this->getVersion();
 172                                 $pattern = '(\$.*) ([0-9a-z_]+\.php) (.*\$)';
 173                                 $replacement = '\\0' . "\n    " . 'http://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/includes/api/\\2';
 174
 175                                 if (is_array($versions)) {
 176                                         foreach ($versions as &$v)
 177                                                 $v = eregi_replace($pattern, $replacement, $v);
 178                                         $versions = implode("\n  ", $versions);
 179                                 }
 180                                 else
 181                                         $versions = eregi_replace($pattern, $replacement, $versions);
 182
 183                                 $msg .= "Version:\n  $versions\n";
 184                         }
 185                 }
 186
 187                 return $msg;
 188         }
 189
 190         public function makeHelpMsgParameters() {
 191                 $params = $this->getAllowedParams();
 192                 if ($params !== false) {
 193
 194                         $paramsDescription = $this->getParamDescription();
 195                         $msg = '';
 196                         $paramPrefix = "\n" . str_repeat(' ', 19);
 197                         foreach ($params as $paramName => $paramSettings) {
 198                                 $desc = isset ($paramsDescription[$paramName]) ? $paramsDescription[$paramName] : '';
 199                                 if (is_array($desc))
 200                                         $desc = implode($paramPrefix, $desc);
 201
 202                                 @ $type = $paramSettings[self :: PARAM_TYPE];
 203                                 if (isset ($type)) {
 204                                         if (isset ($paramSettings[self :: PARAM_ISMULTI]))
 205                                                 $prompt = 'Values (separate with \'|\'): ';
 206                                         else
 207                                                 $prompt = 'One value: ';
 208
 209                                         if (is_array($type)) {
 210                                                 $choices = array();
 211                                                 $nothingPrompt = false;
 212                                                 foreach ($type as $t)
 213                                                         if ($t=='')
 214                                                                 $nothingPrompt = 'Can be empty, or ';
 215                                                         else
 216                                                                 $choices[] =  $t;
 217                                                 $desc .= $paramPrefix . $nothingPrompt . $prompt . implode(', ', $choices);
 218                                         } else {
 219                                                 switch ($type) {
 220                                                         case 'namespace':
 221                                                                 // Special handling because namespaces are type-limited, yet they are not given
 222                                                                 $desc .= $paramPrefix . $prompt . implode(', ', ApiBase :: getValidNamespaces());
 223                                                                 break;
 224                                                         case 'limit':
 225                                                                 $desc .= $paramPrefix . "No more than {$paramSettings[self :: PARAM_MAX]} ({$paramSettings[self :: PARAM_MAX2]} for bots) allowed.";
 226                                                                 break;
 227                                                         case 'integer':
 228                                                                 $hasMin = isset($paramSettings[self :: PARAM_MIN]);
 229                                                                 $hasMax = isset($paramSettings[self :: PARAM_MAX]);
 230                                                                 if ($hasMin || $hasMax) {
 231                                                                         if (!$hasMax)
 232                                                                                 $intRangeStr = "The value must be no less than {$paramSettings[self :: PARAM_MIN]}";
 233                                                                         elseif (!$hasMin)
 234                                                                                 $intRangeStr = "The value must be no more than {$paramSettings[self :: PARAM_MAX]}";
 235                                                                         else
 236                                                                                 $intRangeStr = "The value must be between {$paramSettings[self :: PARAM_MIN]} and {$paramSettings[self :: PARAM_MAX]}";
 237
 238                                                                         $desc .= $paramPrefix . $intRangeStr;
 239                                                                 }
 240                                                                 break;
 241                                                 }
 242                                         }
 243                                 }
 244
 245                                 $default = is_array($paramSettings) ? (isset ($paramSettings[self :: PARAM_DFLT]) ? $paramSettings[self :: PARAM_DFLT] : null) : $paramSettings;
 246                                 if (!is_null($default) && $default !== false)
 247                                         $desc .= $paramPrefix . "Default: $default";
 248
 249                                 $msg .= sprintf("  %-14s - %s\n", $this->encodeParamName($paramName), $desc);
 250                         }
 251                         return $msg;
 252
 253                 } else
 254                         return false;
 255         }
 256
 257         /**
 258          * Returns the description string for this module
 259          */
 260         protected function getDescription() {
 261                 return false;
 262         }
 263
 264         /**
 265          * Returns usage examples for this module. Return null if no examples are available.
 266          */
 267         protected function getExamples() {
 268                 return false;
 269         }
 270
 271         /**
 272          * Returns an array of allowed parameters (keys) => default value for that parameter
 273          */
 274         protected function getAllowedParams() {
 275                 return false;
 276         }
 277
 278         /**
 279          * Returns the description string for the given parameter.
 280          */
 281         protected function getParamDescription() {
 282                 return false;
 283         }
 284
 285         /**
 286          * This method mangles parameter name based on the prefix supplied to the constructor.
 287          * Override this method to change parameter name during runtime
 288          */
 289         public function encodeParamName($paramName) {
 290                 return $this->mParamPrefix . $paramName;
 291         }
 292
 293         /**
 294         * Using getAllowedParams(), makes an array of the values provided by the user,
 295         * with key being the name of the variable, and value - validated value from user or default.
 296         * This method can be used to generate local variables using extract().
 297         */
 298         public function extractRequestParams() {
 299                 $params = $this->getAllowedParams();
 300                 $results = array ();
 301
 302                 foreach ($params as $paramName => $paramSettings)
 303                         $results[$paramName] = $this->getParameterFromSettings($paramName, $paramSettings);
 304
 305                 return $results;
 306         }
 307
 308         /**
 309          * Get a value for the given parameter
 310          */
 311         protected function getParameter($paramName) {
 312                 $params = $this->getAllowedParams();
 313                 $paramSettings = $params[$paramName];
 314                 return $this->getParameterFromSettings($paramName, $paramSettings);
 315         }
 316
 317         public static function getValidNamespaces() {
 318                 static $mValidNamespaces = null;
 319                 if (is_null($mValidNamespaces)) {
 320
 321                         global $wgContLang;
 322                         $mValidNamespaces = array ();
 323                         foreach (array_keys($wgContLang->getNamespaces()) as $ns) {
 324                                 if ($ns >= 0)
 325                                         $mValidNamespaces[] = $ns;
 326                         }
 327                 }
 328                 return $mValidNamespaces;
 329         }
 330
 331         /**
 332          * Using the settings determine the value for the given parameter
 333          * @param $paramName String: parameter name
 334          * @param $paramSettings Mixed: default value or an array of settings using PARAM_* constants.
 335          */
 336         protected function getParameterFromSettings($paramName, $paramSettings) {
 337
 338                 // Some classes may decide to change parameter names
 339                 $paramName = $this->encodeParamName($paramName);
 340
 341                 if (!is_array($paramSettings)) {
 342                         $default = $paramSettings;
 343                         $multi = false;
 344                         $type = gettype($paramSettings);
 345                 } else {
 346                         $default = isset ($paramSettings[self :: PARAM_DFLT]) ? $paramSettings[self :: PARAM_DFLT] : null;
 347                         $multi = isset ($paramSettings[self :: PARAM_ISMULTI]) ? $paramSettings[self :: PARAM_ISMULTI] : false;
 348                         $type = isset ($paramSettings[self :: PARAM_TYPE]) ? $paramSettings[self :: PARAM_TYPE] : null;
 349
 350                         // When type is not given, and no choices, the type is the same as $default
 351                         if (!isset ($type)) {
 352                                 if (isset ($default))
 353                                         $type = gettype($default);
 354                                 else
 355                                         $type = 'NULL'; // allow everything
 356                         }
 357                 }
 358
 359                 if ($type == 'boolean') {
 360                         if (isset ($default) && $default !== false) {
 361                                 // Having a default value of anything other than 'false' is pointless
 362                                 ApiBase :: dieDebug(__METHOD__, "Boolean param $paramName's default is set to '$default'");
 363                         }
 364
 365                         $value = $this->getMain()->getRequest()->getCheck($paramName);
 366                 } else {
 367                         $value = $this->getMain()->getRequest()->getVal($paramName, $default);
 368
 369                         if (isset ($value) && $type == 'namespace')
 370                                 $type = ApiBase :: getValidNamespaces();
 371                 }
 372
 373                 if (isset ($value) && ($multi || is_array($type)))
 374                         $value = $this->parseMultiValue($paramName, $value, $multi, is_array($type) ? $type : null);
 375
 376                 // More validation only when choices were not given
 377                 // choices were validated in parseMultiValue()
 378                 if (isset ($value)) {
 379                         if (!is_array($type)) {
 380                                 switch ($type) {
 381                                         case 'NULL' : // nothing to do
 382                                                 break;
 383                                         case 'string' : // nothing to do
 384                                                 break;
 385                                         case 'integer' : // Force everything using intval() and optionally validate limits
 386
 387                                                 $value = is_array($value) ? array_map('intval', $value) : intval($value);
 388                                                 $checkMin = isset ($paramSettings[self :: PARAM_MIN]);
 389                                                 $checkMax = isset ($paramSettings[self :: PARAM_MAX]);
 390
 391                                                 if ($checkMin || $checkMax) {
 392                                                         $min = $checkMin ? $paramSettings[self :: PARAM_MIN] : false;
 393                                                         $max = $checkMax ? $paramSettings[self :: PARAM_MAX] : false;
 394
 395                                                         $values = is_array($value) ? $value : array($value);
 396                                                         foreach ($values as $v) {
 397                                                                 if ($checkMin && $v < $min)
 398                                                                         $this->dieUsage("$paramName may not be less than $min (set to $v)", $paramName);
 399                                                                 if ($checkMax && $v > $max)
 400                                                                         $this->dieUsage("$paramName may not be over $max (set to $v)", $paramName);
 401                                                         }
 402                                                 }
 403                                                 break;
 404                                         case 'limit' :
 405                                                 if (!isset ($paramSettings[self :: PARAM_MAX]) || !isset ($paramSettings[self :: PARAM_MAX2]))
 406                                                         ApiBase :: dieDebug(__METHOD__, "MAX1 or MAX2 are not defined for the limit $paramName");
 407                                                 if ($multi)
 408                                                         ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
 409                                                 $min = isset ($paramSettings[self :: PARAM_MIN]) ? $paramSettings[self :: PARAM_MIN] : 0;
 410                                                 $value = intval($value);
 411                                                 $this->validateLimit($paramName, $value, $min, $paramSettings[self :: PARAM_MAX], $paramSettings[self :: PARAM_MAX2]);
 412                                                 break;
 413                                         case 'boolean' :
 414                                                 if ($multi)
 415                                                         ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
 416                                                 break;
 417                                         case 'timestamp' :
 418                                                 if ($multi)
 419                                                         ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
 420                                                 $value = wfTimestamp(TS_UNIX, $value);
 421                                                 if ($value === 0)
 422                                                         $this->dieUsage("Invalid value '$value' for timestamp parameter $paramName", "badtimestamp_{$paramName}");
 423                                                 $value = wfTimestamp(TS_MW, $value);
 424                                                 break;
 425                                         case 'user' :
 426                                                 $title = Title::makeTitleSafe( NS_USER, $value );
 427                                                 if ( is_null( $title ) )
 428                                                         $this->dieUsage("Invalid value $user for user parameter $paramName", "baduser_{$paramName}");
 429                                                 $value = $title->getText();
 430                                                 break;
 431                                         default :
 432                                                 ApiBase :: dieDebug(__METHOD__, "Param $paramName's type is unknown - $type");
 433                                 }
 434                         }
 435
 436                         // There should never be any duplicate values in a list
 437                         if (is_array($value))
 438                                 $value = array_unique($value);
 439                 }
 440
 441                 return $value;
 442         }
 443
 444         /**
 445         * Return an array of values that were given in a 'a|b|c' notation,
 446         * after it optionally validates them against the list allowed values.
 447         *
 448         * @param valueName - The name of the parameter (for error reporting)
 449         * @param value - The value being parsed
 450         * @param allowMultiple - Can $value contain more than one value separated by '|'?
 451         * @param allowedValues - An array of values to check against. If null, all values are accepted.
 452         * @return (allowMultiple ? an_array_of_values : a_single_value)
 453         */
 454         protected function parseMultiValue($valueName, $value, $allowMultiple, $allowedValues) {
 455                 $valuesList = explode('|', $value);
 456                 if (!$allowMultiple && count($valuesList) != 1) {
 457                         $possibleValues = is_array($allowedValues) ? "of '" . implode("', '", $allowedValues) . "'" : '';
 458                         $this->dieUsage("Only one $possibleValues is allowed for parameter '$valueName'", "multival_$valueName");
 459                 }
 460                 if (is_array($allowedValues)) {
 461                         $unknownValues = array_diff($valuesList, $allowedValues);
 462                         if ($unknownValues) {
 463                                 $this->dieUsage('Unrecognised value' . (count($unknownValues) > 1 ? "s" : "") . " for parameter '$valueName'", "unknown_$valueName");
 464                         }
 465                 }
 466
 467                 return $allowMultiple ? $valuesList : $valuesList[0];
 468         }
 469
 470         /**
 471         * Validate the value against the minimum and user/bot maximum limits. Prints usage info on failure.
 472         */
 473         function validateLimit($varname, $value, $min, $max, $botMax) {
 474                 if ($value < $min) {
 475                         $this->dieUsage("$varname may not be less than $min (set to $value)", $varname);
 476                 }
 477
 478                 if ($this->getMain()->isBot() || $this->getMain()->isSysop()) {
 479                         if ($value > $botMax) {
 480                                 $this->dieUsage("$varname may not be over $botMax (set to $value) for bots or sysops", $varname);
 481                         }
 482                 }
 483                 elseif ($value > $max) {
 484                         $this->dieUsage("$varname may not be over $max (set to $value) for users", $varname);
 485                 }
 486         }
 487
 488         /**
 489          * Call main module's error handler
 490          */
 491         public function dieUsage($description, $errorCode, $httpRespCode = 0) {
 492                 throw new UsageException($description, $this->encodeParamName($errorCode), $httpRespCode);
 493         }
 494
 495         /**
 496          * Internal code errors should be reported with this method
 497          */
 498         protected static function dieDebug($method, $message) {
 499                 wfDebugDieBacktrace("Internal error in $method: $message");
 500         }
 501
 502         /**
 503          * Profiling: total module execution time
 504          */
 505         private $mTimeIn = 0, $mModuleTime = 0;
 506
 507         /**
 508          * Start module profiling
 509          */
 510         public function profileIn() {
 511                 if ($this->mTimeIn !== 0)
 512                         ApiBase :: dieDebug(__METHOD__, 'called twice without calling profileOut()');
 513                 $this->mTimeIn = microtime(true);
 514                 wfProfileIn($this->getModuleProfileName());
 515         }
 516
 517         /**
 518          * End module profiling
 519          */
 520         public function profileOut() {
 521                 if ($this->mTimeIn === 0)
 522                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileIn() first');
 523                 if ($this->mDBTimeIn !== 0)
 524                         ApiBase :: dieDebug(__METHOD__, 'must be called after database profiling is done with profileDBOut()');
 525
 526                 $this->mModuleTime += microtime(true) - $this->mTimeIn;
 527                 $this->mTimeIn = 0;
 528                 wfProfileOut($this->getModuleProfileName());
 529         }
 530
 531         /**
 532          * When modules crash, sometimes it is needed to do a profileOut() regardless
 533          * of the profiling state the module was in. This method does such cleanup.
 534          */
 535         public function safeProfileOut() {
 536                 if ($this->mTimeIn !== 0) {
 537                         if ($this->mDBTimeIn !== 0)
 538                                 $this->profileDBOut();
 539                         $this->profileOut();
 540                 }
 541         }
 542
 543         /**
 544          * Total time the module was executed
 545          */
 546         public function getProfileTime() {
 547                 if ($this->mTimeIn !== 0)
 548                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileOut() first');
 549                 return $this->mModuleTime;
 550         }
 551
 552         /**
 553          * Profiling: database execution time
 554          */
 555         private $mDBTimeIn = 0, $mDBTime = 0;
 556
 557         /**
 558          * Start module profiling
 559          */
 560         public function profileDBIn() {
 561                 if ($this->mTimeIn === 0)
 562                         ApiBase :: dieDebug(__METHOD__, 'must be called while profiling the entire module with profileIn()');
 563                 if ($this->mDBTimeIn !== 0)
 564                         ApiBase :: dieDebug(__METHOD__, 'called twice without calling profileDBOut()');
 565                 $this->mDBTimeIn = microtime(true);
 566                 wfProfileIn($this->getModuleProfileName(true));
 567         }
 568
 569         /**
 570          * End database profiling
 571          */
 572         public function profileDBOut() {
 573                 if ($this->mTimeIn === 0)
 574                         ApiBase :: dieDebug(__METHOD__, 'must be called while profiling the entire module with profileIn()');
 575                 if ($this->mDBTimeIn === 0)
 576                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileDBIn() first');
 577
 578                 $time = microtime(true) - $this->mDBTimeIn;
 579                 $this->mDBTimeIn = 0;
 580
 581                 $this->mDBTime += $time;
 582                 $this->getMain()->mDBTime += $time;
 583                 wfProfileOut($this->getModuleProfileName(true));
 584         }
 585
 586         /**
 587          * Total time the module used the database
 588          */
 589         public function getProfileDBTime() {
 590                 if ($this->mDBTimeIn !== 0)
 591                         ApiBase :: dieDebug(__METHOD__, 'called without calling profileDBOut() first');
 592                 return $this->mDBTime;
 593         }
 594
 595         public static function debugPrint($value, $name = 'unknown', $backtrace = false) {
 596                 print "\n\n<pre><b>Debuging value '$name':</b>\n\n";
 597                 var_export($value);
 598                 if ($backtrace)
 599                         print "\n" . wfBacktrace();
 600                 print "\n</pre>\n";
 601         }
 602
 603         public abstract function getVersion();
 604
 605         public static function getBaseVersion() {
 606                 return __CLASS__ . ': $Id$';
 607         }
 608 }
 609 ?>