Update to MediaWiki 1.24.1

1 files changed, 1416 insertions, 851 deletions

diff --git a/includes/api/ApiBase.php b/includes/api/ApiBase.php
index c1454e76..944e4895 100644
--- a/includes/api/ApiBase.php
+++ b/includes/api/ApiBase.php
@@ -30,36 +30,40 @@
  * The class functions are divided into several areas of functionality:
  *
  * Module parameters: Derived classes can define getAllowedParams() to specify
- * 	which parameters to expect, how to parse and validate them.
+ *    which parameters to expect, how to parse and validate them.
  *
  * Profiling: various methods to allow keeping tabs on various tasks and their
- * 	time costs
+ *    time costs
  *
  * Self-documentation: code to allow the API to document its own state
  *
  * @ingroup API
  */
 abstract class ApiBase extends ContextSource {
-
 	// These constants allow modules to specify exactly how to treat incoming parameters.
 
-	const PARAM_DFLT = 0; // Default value of the parameter
-	const PARAM_ISMULTI = 1; // Boolean, do we accept more than one item for this parameter (e.g.: titles)?
-	const PARAM_TYPE = 2; // Can be either a string type (e.g.: 'integer') or an array of allowed values
-	const PARAM_MAX = 3; // Max value allowed for a parameter. Only applies if TYPE='integer'
-	const PARAM_MAX2 = 4; // Max value allowed for a parameter for bots and sysops. Only applies if TYPE='integer'
-	const PARAM_MIN = 5; // Lowest value allowed for a parameter. Only applies if TYPE='integer'
-	const PARAM_ALLOW_DUPLICATES = 6; // Boolean, do we allow the same value to be set more than once when ISMULTI=true
-	const PARAM_DEPRECATED = 7; // Boolean, is the parameter deprecated (will show a warning)
+	// Default value of the parameter
+	const PARAM_DFLT = 0;
+	// Boolean, do we accept more than one item for this parameter (e.g.: titles)?
+	const PARAM_ISMULTI = 1;
+	// Can be either a string type (e.g.: 'integer') or an array of allowed values
+	const PARAM_TYPE = 2;
+	// Max value allowed for a parameter. Only applies if TYPE='integer'
+	const PARAM_MAX = 3;
+	// Max value allowed for a parameter for bots and sysops. Only applies if TYPE='integer'
+	const PARAM_MAX2 = 4;
+	// Lowest value allowed for a parameter. Only applies if TYPE='integer'
+	const PARAM_MIN = 5;
+	// Boolean, do we allow the same value to be set more than once when ISMULTI=true
+	const PARAM_ALLOW_DUPLICATES = 6;
+	// Boolean, is the parameter deprecated (will show a warning)
+	const PARAM_DEPRECATED = 7;
 	/// @since 1.17
 	const PARAM_REQUIRED = 8; // Boolean, is the parameter required?
 	/// @since 1.17
-	const PARAM_RANGE_ENFORCE = 9; // Boolean, if MIN/MAX are set, enforce (die) these? Only applies if TYPE='integer' Use with extreme caution
-
-	const PROP_ROOT = 'ROOT'; // Name of property group that is on the root element of the result, i.e. not part of a list
-	const PROP_LIST = 'LIST'; // Boolean, is the result multiple items? Defaults to true for query modules, to false for other modules
-	const PROP_TYPE = 0; // Type of the property, uses same format as PARAM_TYPE
-	const PROP_NULLABLE = 1; // Boolean, can the property be not included in the result? Defaults to false
+	// Boolean, if MIN/MAX are set, enforce (die) these?
+	// Only applies if TYPE='integer' Use with extreme caution
+	const PARAM_RANGE_ENFORCE = 9;
 
 	const LIMIT_BIG1 = 500; // Fast query, std user limit
 	const LIMIT_BIG2 = 5000; // Fast query, bot/sysop limit
@@ -73,17 +77,19 @@ abstract class ApiBase extends ContextSource {
 	 */
 	const GET_VALUES_FOR_HELP = 1;
 
-	private $mMainModule, $mModuleName, $mModulePrefix;
+	/** @var ApiMain */
+	private $mMainModule;
+	/** @var string */
+	private $mModuleName, $mModulePrefix;
 	private $mSlaveDB = null;
 	private $mParamCache = array();
 
 	/**
-	 * Constructor
-	 * @param $mainModule ApiMain object
+	 * @param ApiMain $mainModule
 	 * @param string $moduleName Name of this module
 	 * @param string $modulePrefix Prefix to use for parameter names
 	 */
-	public function __construct( $mainModule, $moduleName, $modulePrefix = '' ) {
+	public function __construct( ApiMain $mainModule, $moduleName, $modulePrefix = '' ) {
 		$this->mMainModule = $mainModule;
 		$this->mModuleName = $moduleName;
 		$this->mModulePrefix = $modulePrefix;
@@ -93,9 +99,11 @@ abstract class ApiBase extends ContextSource {
 		}
 	}
 
-	/*****************************************************************************
-	 * ABSTRACT METHODS                                                          *
-	 *****************************************************************************/
+
+	/************************************************************************//**
+	 * @name   Methods to implement
+	 * @{
+	 */
 
 	/**
 	 * Evaluates the parameters, performs the requested query, and sets up
@@ -116,432 +124,232 @@ abstract class ApiBase extends ContextSource {
 	abstract public function execute();
 
 	/**
-	 * Returns a string that identifies the version of the extending class.
-	 * Typically includes the class name, the svn revision, timestamp, and
-	 * last author. Usually done with SVN's Id keyword
-	 * @return string
-	 * @deprecated since 1.21, version string is no longer supported
+	 * Get the module manager, or null if this module has no sub-modules
+	 * @since 1.21
+	 * @return ApiModuleManager
 	 */
-	public function getVersion() {
-		wfDeprecated( __METHOD__, '1.21' );
-		return '';
+	public function getModuleManager() {
+		return null;
 	}
 
 	/**
-	 * Get the name of the module being executed by this instance
-	 * @return string
+	 * If the module may only be used with a certain format module,
+	 * it should override this method to return an instance of that formatter.
+	 * A value of null means the default format will be used.
+	 * @return mixed Instance of a derived class of ApiFormatBase, or null
 	 */
-	public function getModuleName() {
-		return $this->mModuleName;
+	public function getCustomPrinter() {
+		return null;
 	}
 
 	/**
-	 * Get the module manager, or null if this module has no sub-modules
-	 * @since 1.21
-	 * @return ApiModuleManager
+	 * Returns the description string for this module
+	 * @return string|array
 	 */
-	public function getModuleManager() {
-		return null;
+	protected function getDescription() {
+		return false;
 	}
 
 	/**
-	 * Get parameter prefix (usually two letters or an empty string).
-	 * @return string
+	 * Returns usage examples for this module. Return false if no examples are available.
+	 * @return bool|string|array
 	 */
-	public function getModulePrefix() {
-		return $this->mModulePrefix;
+	protected function getExamples() {
+		return false;
 	}
 
 	/**
-	 * Get the name of the module as shown in the profiler log
+	 * @return bool|string|array Returns a false if the module has no help URL,
+	 *   else returns a (array of) string
+	 */
+	public function getHelpUrls() {
+		return false;
+	}
+
+	/**
+	 * Returns an array of allowed parameters (parameter name) => (default
+	 * value) or (parameter name) => (array with PARAM_* constants as keys)
+	 * Don't call this function directly: use getFinalParams() to allow
+	 * hooks to modify parameters as needed.
 	 *
-	 * @param $db DatabaseBase|bool
+	 * Some derived classes may choose to handle an integer $flags parameter
+	 * in the overriding methods. Callers of this method can pass zero or
+	 * more OR-ed flags like GET_VALUES_FOR_HELP.
 	 *
-	 * @return string
+	 * @return array|bool
 	 */
-	public function getModuleProfileName( $db = false ) {
-		if ( $db ) {
-			return 'API:' . $this->mModuleName . '-DB';
-		} else {
-			return 'API:' . $this->mModuleName;
-		}
+	protected function getAllowedParams( /* $flags = 0 */ ) {
+		// int $flags is not declared because it causes "Strict standards"
+		// warning. Most derived classes do not implement it.
+		return false;
 	}
 
 	/**
-	 * Get the main module
-	 * @return ApiMain object
+	 * Returns an array of parameter descriptions.
+	 * Don't call this function directly: use getFinalParamDescription() to
+	 * allow hooks to modify descriptions as needed.
+	 * @return array|bool False on no parameter descriptions
 	 */
-	public function getMain() {
-		return $this->mMainModule;
+	protected function getParamDescription() {
+		return false;
 	}
 
 	/**
-	 * Returns true if this module is the main module ($this === $this->mMainModule),
-	 * false otherwise.
+	 * Indicates if this module needs maxlag to be checked
 	 * @return bool
 	 */
-	public function isMain() {
-		return $this === $this->mMainModule;
+	public function shouldCheckMaxlag() {
+		return true;
 	}
 
 	/**
-	 * Get the result object
-	 * @return ApiResult
+	 * Indicates whether this module requires read rights
+	 * @return bool
 	 */
-	public function getResult() {
-		// Main module has getResult() method overridden
-		// Safety - avoid infinite loop:
-		if ( $this->isMain() ) {
-			ApiBase::dieDebug( __METHOD__, 'base method was called on main module. ' );
-		}
-		return $this->getMain()->getResult();
+	public function isReadMode() {
+		return true;
 	}
 
 	/**
-	 * Get the result data array (read-only)
-	 * @return array
+	 * Indicates whether this module requires write mode
+	 * @return bool
 	 */
-	public function getResultData() {
-		return $this->getResult()->getData();
+	public function isWriteMode() {
+		return false;
 	}
 
 	/**
-	 * Create a new RequestContext object to use e.g. for calls to other parts
-	 * the software.
-	 * The object will have the WebRequest and the User object set to the ones
-	 * used in this instance.
-	 *
-	 * @deprecated since 1.19 use getContext to get the current context
-	 * @return DerivativeContext
+	 * Indicates whether this module must be called with a POST request
+	 * @return bool
 	 */
-	public function createContext() {
-		wfDeprecated( __METHOD__, '1.19' );
-		return new DerivativeContext( $this->getContext() );
+	public function mustBePosted() {
+		return $this->needsToken() !== false;
 	}
 
 	/**
-	 * Set warning section for this module. Users should monitor this
-	 * section to notice any changes in API. Multiple calls to this
-	 * function will result in the warning messages being separated by
-	 * newlines
-	 * @param string $warning Warning message
+	 * Returns the token type this module requires in order to execute.
+	 *
+	 * Modules are strongly encouraged to use the core 'csrf' type unless they
+	 * have specialized security needs. If the token type is not one of the
+	 * core types, you must use the ApiQueryTokensRegisterTypes hook to
+	 * register it.
+	 *
+	 * Returning a non-falsey value here will cause self::getFinalParams() to
+	 * return a required string 'token' parameter and
+	 * self::getFinalParamDescription() to ensure there is standardized
+	 * documentation for it. Also, self::mustBePosted() must return true when
+	 * tokens are used.
+	 *
+	 * In previous versions of MediaWiki, true was a valid return value.
+	 * Returning true will generate errors indicating that the API module needs
+	 * updating.
+	 *
+	 * @return string|false
 	 */
-	public function setWarning( $warning ) {
-		$result = $this->getResult();
-		$data = $result->getData();
-		$moduleName = $this->getModuleName();
-		if ( isset( $data['warnings'][$moduleName] ) ) {
-			// Don't add duplicate warnings
-			$oldWarning = $data['warnings'][$moduleName]['*'];
-			$warnPos = strpos( $oldWarning, $warning );
-			// If $warning was found in $oldWarning, check if it starts at 0 or after "\n"
-			if ( $warnPos !== false && ( $warnPos === 0 || $oldWarning[$warnPos - 1] === "\n" ) ) {
-				// Check if $warning is followed by "\n" or the end of the $oldWarning
-				$warnPos += strlen( $warning );
-				if ( strlen( $oldWarning ) <= $warnPos || $oldWarning[$warnPos] === "\n" ) {
-					return;
-				}
-			}
-			// If there is a warning already, append it to the existing one
-			$warning = "$oldWarning\n$warning";
-		}
-		$msg = array();
-		ApiResult::setContent( $msg, $warning );
-		$result->disableSizeCheck();
-		$result->addValue( 'warnings', $moduleName,
-			$msg, ApiResult::OVERRIDE | ApiResult::ADD_ON_TOP );
-		$result->enableSizeCheck();
+	public function needsToken() {
+		return false;
 	}
 
 	/**
-	 * If the module may only be used with a certain format module,
-	 * it should override this method to return an instance of that formatter.
-	 * A value of null means the default format will be used.
-	 * @return mixed instance of a derived class of ApiFormatBase, or null
+	 * Fetch the salt used in the Web UI corresponding to this module.
+	 *
+	 * Only override this if the Web UI uses a token with a non-constant salt.
+	 *
+	 * @since 1.24
+	 * @param array $params All supplied parameters for the module
+	 * @return string|array|null
 	 */
-	public function getCustomPrinter() {
+	protected function getWebUITokenSalt( array $params ) {
 		return null;
 	}
 
-	/**
-	 * Generates help message for this module, or false if there is no description
-	 * @return mixed string or false
-	 */
-	public function makeHelpMsg() {
-		static $lnPrfx = "\n  ";
-
-		$msg = $this->getFinalDescription();
-
-		if ( $msg !== false ) {
-
-			if ( !is_array( $msg ) ) {
-				$msg = array(
-					$msg
-				);
-			}
-			$msg = $lnPrfx . implode( $lnPrfx, $msg ) . "\n";
+	/**@}*/
 
-			$msg .= $this->makeHelpArrayToString( $lnPrfx, false, $this->getHelpUrls() );
-
-			if ( $this->isReadMode() ) {
-				$msg .= "\nThis module requires read rights";
-			}
-			if ( $this->isWriteMode() ) {
-				$msg .= "\nThis module requires write rights";
-			}
-			if ( $this->mustBePosted() ) {
-				$msg .= "\nThis module only accepts POST requests";
-			}
-			if ( $this->isReadMode() || $this->isWriteMode() ||
-					$this->mustBePosted() ) {
-				$msg .= "\n";
-			}
-
-			// Parameters
-			$paramsMsg = $this->makeHelpMsgParameters();
-			if ( $paramsMsg !== false ) {
-				$msg .= "Parameters:\n$paramsMsg";
-			}
-
-			$examples = $this->getExamples();
-			if ( $examples ) {
-				if ( !is_array( $examples ) ) {
-					$examples = array(
-						$examples
-					);
-				}
-				$msg .= "Example" . ( count( $examples ) > 1 ? 's' : '' ) . ":\n";
-				foreach ( $examples as $k => $v ) {
-					if ( is_numeric( $k ) ) {
-						$msg .= "  $v\n";
-					} else {
-						if ( is_array( $v ) ) {
-							$msgExample = implode( "\n", array_map( array( $this, 'indentExampleText' ), $v ) );
-						} else {
-							$msgExample = "  $v";
-						}
-						$msgExample .= ":";
-						$msg .= wordwrap( $msgExample, 100, "\n" ) . "\n    $k\n";
-					}
-				}
-			}
-		}
-
-		return $msg;
-	}
+	/************************************************************************//**
+	 * @name   Data access methods
+	 * @{
+	 */
 
 	/**
-	 * @param $item string
+	 * Get the name of the module being executed by this instance
 	 * @return string
 	 */
-	private function indentExampleText( $item ) {
-		return "  " . $item;
+	public function getModuleName() {
+		return $this->mModuleName;
 	}
 
 	/**
-	 * @param string $prefix Text to split output items
-	 * @param string $title What is being output
-	 * @param $input string|array
+	 * Get parameter prefix (usually two letters or an empty string).
 	 * @return string
 	 */
-	protected function makeHelpArrayToString( $prefix, $title, $input ) {
-		if ( $input === false ) {
-			return '';
-		}
-		if ( !is_array( $input ) ) {
-			$input = array( $input );
-		}
-
-		if ( count( $input ) > 0 ) {
-			if ( $title ) {
-				$msg = $title . ( count( $input ) > 1 ? 's' : '' ) . ":\n  ";
-			} else {
-				$msg = '  ';
-			}
-			$msg .= implode( $prefix, $input ) . "\n";
-			return $msg;
-		}
-		return '';
+	public function getModulePrefix() {
+		return $this->mModulePrefix;
 	}
 
 	/**
-	 * Generates the parameter descriptions for this module, to be displayed in the
-	 * module's help.
-	 * @return string or false
+	 * Get the main module
+	 * @return ApiMain
 	 */
-	public function makeHelpMsgParameters() {
-		$params = $this->getFinalParams( ApiBase::GET_VALUES_FOR_HELP );
-		if ( $params ) {
-
-			$paramsDescription = $this->getFinalParamDescription();
-			$msg = '';
-			$paramPrefix = "\n" . str_repeat( ' ', 24 );
-			$descWordwrap = "\n" . str_repeat( ' ', 28 );
-			foreach ( $params as $paramName => $paramSettings ) {
-				$desc = isset( $paramsDescription[$paramName] ) ? $paramsDescription[$paramName] : '';
-				if ( is_array( $desc ) ) {
-					$desc = implode( $paramPrefix, $desc );
-				}
-
-				//handle shorthand
-				if ( !is_array( $paramSettings ) ) {
-					$paramSettings = array(
-						self::PARAM_DFLT => $paramSettings,
-					);
-				}
-
-				//handle missing type
-				if ( !isset( $paramSettings[ApiBase::PARAM_TYPE] ) ) {
-					$dflt = isset( $paramSettings[ApiBase::PARAM_DFLT] ) ? $paramSettings[ApiBase::PARAM_DFLT] : null;
-					if ( is_bool( $dflt ) ) {
-						$paramSettings[ApiBase::PARAM_TYPE] = 'boolean';
-					} elseif ( is_string( $dflt ) || is_null( $dflt ) ) {
-						$paramSettings[ApiBase::PARAM_TYPE] = 'string';
-					} elseif ( is_int( $dflt ) ) {
-						$paramSettings[ApiBase::PARAM_TYPE] = 'integer';
-					}
-				}
-
-				if ( isset( $paramSettings[self::PARAM_DEPRECATED] ) && $paramSettings[self::PARAM_DEPRECATED] ) {
-					$desc = "DEPRECATED! $desc";
-				}
-
-				if ( isset( $paramSettings[self::PARAM_REQUIRED] ) && $paramSettings[self::PARAM_REQUIRED] ) {
-					$desc .= $paramPrefix . "This parameter is required";
-				}
-
-				$type = isset( $paramSettings[self::PARAM_TYPE] ) ? $paramSettings[self::PARAM_TYPE] : null;
-				if ( isset( $type ) ) {
-					$hintPipeSeparated = true;
-					$multi = isset( $paramSettings[self::PARAM_ISMULTI] ) ? $paramSettings[self::PARAM_ISMULTI] : false;
-					if ( $multi ) {
-						$prompt = 'Values (separate with \'|\'): ';
-					} else {
-						$prompt = 'One value: ';
-					}
-
-					if ( is_array( $type ) ) {
-						$choices = array();
-						$nothingPrompt = '';
-						foreach ( $type as $t ) {
-							if ( $t === '' ) {
-								$nothingPrompt = 'Can be empty, or ';
-							} else {
-								$choices[] = $t;
-							}
-						}
-						$desc .= $paramPrefix . $nothingPrompt . $prompt;
-						$choicesstring = implode( ', ', $choices );
-						$desc .= wordwrap( $choicesstring, 100, $descWordwrap );
-						$hintPipeSeparated = false;
-					} else {
-						switch ( $type ) {
-							case 'namespace':
-								// Special handling because namespaces are type-limited, yet they are not given
-								$desc .= $paramPrefix . $prompt;
-								$desc .= wordwrap( implode( ', ', MWNamespace::getValidNamespaces() ),
-									100, $descWordwrap );
-								$hintPipeSeparated = false;
-								break;
-							case 'limit':
-								$desc .= $paramPrefix . "No more than {$paramSettings[self::PARAM_MAX]}";
-								if ( isset( $paramSettings[self::PARAM_MAX2] ) ) {
-									$desc .= " ({$paramSettings[self::PARAM_MAX2]} for bots)";
-								}
-								$desc .= ' allowed';
-								break;
-							case 'integer':
-								$s = $multi ? 's' : '';
-								$hasMin = isset( $paramSettings[self::PARAM_MIN] );
-								$hasMax = isset( $paramSettings[self::PARAM_MAX] );
-								if ( $hasMin || $hasMax ) {
-									if ( !$hasMax ) {
-										$intRangeStr = "The value$s must be no less than {$paramSettings[self::PARAM_MIN]}";
-									} elseif ( !$hasMin ) {
-										$intRangeStr = "The value$s must be no more than {$paramSettings[self::PARAM_MAX]}";
-									} else {
-										$intRangeStr = "The value$s must be between {$paramSettings[self::PARAM_MIN]} and {$paramSettings[self::PARAM_MAX]}";
-									}
-
-									$desc .= $paramPrefix . $intRangeStr;
-								}
-								break;
-							case 'upload':
-								$desc .= $paramPrefix . "Must be posted as a file upload using multipart/form-data";
-								break;
-						}
-					}
-
-					if ( $multi ) {
-						if ( $hintPipeSeparated ) {
-							$desc .= $paramPrefix . "Separate values with '|'";
-						}
-
-						$isArray = is_array( $type );
-						if ( !$isArray
-								|| $isArray && count( $type ) > self::LIMIT_SML1 ) {
-							$desc .= $paramPrefix . "Maximum number of values " .
-									self::LIMIT_SML1 . " (" . self::LIMIT_SML2 . " for bots)";
-						}
-					}
-				}
-
-				$default = isset( $paramSettings[self::PARAM_DFLT] ) ? $paramSettings[self::PARAM_DFLT] : null;
-				if ( !is_null( $default ) && $default !== false ) {
-					$desc .= $paramPrefix . "Default: $default";
-				}
-
-				$msg .= sprintf( "  %-19s - %s\n", $this->encodeParamName( $paramName ), $desc );
-			}
-			return $msg;
+	public function getMain() {
+		return $this->mMainModule;
+	}
 
-		} else {
-			return false;
-		}
+	/**
+	 * Returns true if this module is the main module ($this === $this->mMainModule),
+	 * false otherwise.
+	 * @return bool
+	 */
+	public function isMain() {
+		return $this === $this->mMainModule;
 	}
 
 	/**
-	 * Returns the description string for this module
-	 * @return mixed string or array of strings
+	 * Get the result object
+	 * @return ApiResult
 	 */
-	protected function getDescription() {
-		return false;
+	public function getResult() {
+		// Main module has getResult() method overridden
+		// Safety - avoid infinite loop:
+		if ( $this->isMain() ) {
+			ApiBase::dieDebug( __METHOD__, 'base method was called on main module. ' );
+		}
+
+		return $this->getMain()->getResult();
 	}
 
 	/**
-	 * Returns usage examples for this module. Return false if no examples are available.
-	 * @return bool|string|array
+	 * Get the result data array (read-only)
+	 * @return array
 	 */
-	protected function getExamples() {
-		return false;
+	public function getResultData() {
+		return $this->getResult()->getData();
 	}
 
 	/**
-	 * Returns an array of allowed parameters (parameter name) => (default
-	 * value) or (parameter name) => (array with PARAM_* constants as keys)
-	 * Don't call this function directly: use getFinalParams() to allow
-	 * hooks to modify parameters as needed.
-	 *
-	 * Some derived classes may choose to handle an integer $flags parameter
-	 * in the overriding methods. Callers of this method can pass zero or
-	 * more OR-ed flags like GET_VALUES_FOR_HELP.
-	 *
-	 * @return array|bool
+	 * Gets a default slave database connection object
+	 * @return DatabaseBase
 	 */
-	protected function getAllowedParams( /* $flags = 0 */ ) {
-		// int $flags is not declared because it causes "Strict standards"
-		// warning. Most derived classes do not implement it.
-		return false;
+	protected function getDB() {
+		if ( !isset( $this->mSlaveDB ) ) {
+			$this->profileDBIn();
+			$this->mSlaveDB = wfGetDB( DB_SLAVE, 'api' );
+			$this->profileDBOut();
+		}
+
+		return $this->mSlaveDB;
 	}
 
 	/**
-	 * Returns an array of parameter descriptions.
-	 * Don't call this function directly: use getFinalParamDescription() to
-	 * allow hooks to modify descriptions as needed.
-	 * @return array|bool False on no parameter descriptions
+	 * Get final module description, after hooks have had a chance to tweak it as
+	 * needed.
+	 *
+	 * @return array|bool False on no parameters
 	 */
-	protected function getParamDescription() {
-		return false;
+	public function getFinalDescription() {
+		$desc = $this->getDescription();
+		wfRunHooks( 'APIGetDescription', array( &$this, &$desc ) );
+
+		return $desc;
 	}
 
 	/**
@@ -549,12 +357,21 @@ abstract class ApiBase extends ContextSource {
 	 * tweak it as needed.
 	 *
 	 * @param int $flags Zero or more flags like GET_VALUES_FOR_HELP
-	 * @return array|Bool False on no parameters
+	 * @return array|bool False on no parameters
 	 * @since 1.21 $flags param added
 	 */
 	public function getFinalParams( $flags = 0 ) {
 		$params = $this->getAllowedParams( $flags );
+
+		if ( $this->needsToken() ) {
+			$params['token'] = array(
+				ApiBase::PARAM_TYPE => 'string',
+				ApiBase::PARAM_REQUIRED => true,
+			);
+		}
+
 		wfRunHooks( 'APIGetAllowedParams', array( &$this, &$params, $flags ) );
+
 		return $params;
 	}
 
@@ -566,67 +383,33 @@ abstract class ApiBase extends ContextSource {
 	 */
 	public function getFinalParamDescription() {
 		$desc = $this->getParamDescription();
-		wfRunHooks( 'APIGetParamDescription', array( &$this, &$desc ) );
-		return $desc;
-	}
 
-	/**
-	 * Returns possible properties in the result, grouped by the value of the prop parameter
-	 * that shows them.
-	 *
-	 * Properties that are shown always are in a group with empty string as a key.
-	 * Properties that can be shown by several values of prop are included multiple times.
-	 * If some properties are part of a list and some are on the root object (see ApiQueryQueryPage),
-	 * those on the root object are under the key PROP_ROOT.
-	 * The array can also contain a boolean under the key PROP_LIST,
-	 * indicating whether the result is a list.
-	 *
-	 * Don't call this function directly: use getFinalResultProperties() to
-	 * allow hooks to modify descriptions as needed.
-	 *
-	 * @return array|bool False on no properties
-	 */
-	protected function getResultProperties() {
-		return false;
-	}
-
-	/**
-	 * Get final possible result properties, after hooks have had a chance to tweak it as
-	 * needed.
-	 *
-	 * @return array
-	 */
-	public function getFinalResultProperties() {
-		$properties = $this->getResultProperties();
-		wfRunHooks( 'APIGetResultProperties', array( $this, &$properties ) );
-		return $properties;
-	}
-
-	/**
-	 * Add token properties to the array used by getResultProperties,
-	 * based on a token functions mapping.
-	 */
-	protected static function addTokenProperties( &$props, $tokenFunctions ) {
-		foreach ( array_keys( $tokenFunctions ) as $token ) {
-			$props[''][$token . 'token'] = array(
-				ApiBase::PROP_TYPE => 'string',
-				ApiBase::PROP_NULLABLE => true
+		$tokenType = $this->needsToken();
+		if ( $tokenType ) {
+			if ( !isset( $desc['token'] ) ) {
+				$desc['token'] = array();
+			} elseif ( !is_array( $desc['token'] ) ) {
+				// We ignore a plain-string token, because it's probably an
+				// extension that is supplying the string for BC.
+				$desc['token'] = array();
+			}
+			array_unshift( $desc['token'],
+				"A '$tokenType' token retrieved from action=query&meta=tokens"
 			);
 		}
-	}
 
-	/**
-	 * Get final module description, after hooks have had a chance to tweak it as
-	 * needed.
-	 *
-	 * @return array|bool False on no parameters
-	 */
-	public function getFinalDescription() {
-		$desc = $this->getDescription();
-		wfRunHooks( 'APIGetDescription', array( &$this, &$desc ) );
+		wfRunHooks( 'APIGetParamDescription', array( &$this, &$desc ) );
+
 		return $desc;
 	}
 
+	/**@}*/
+
+	/************************************************************************//**
+	 * @name   Parameter handling
+	 * @{
+	 */
+
 	/**
 	 * This method mangles parameter name based on the prefix supplied to the constructor.
 	 * Override this method to change parameter name during runtime
@@ -643,7 +426,7 @@ abstract class ApiBase extends ContextSource {
 	 * value - validated value from user or default. limits will not be
 	 * parsed if $parseLimit is set to false; use this when the max
 	 * limit is not definitive yet, e.g. when getting revisions.
-	 * @param $parseLimit Boolean: true by default
+	 * @param bool $parseLimit True by default
 	 * @return array
 	 */
 	public function extractRequestParams( $parseLimit = true ) {
@@ -660,26 +443,30 @@ abstract class ApiBase extends ContextSource {
 			}
 			$this->mParamCache[$parseLimit] = $results;
 		}
+
 		return $this->mParamCache[$parseLimit];
 	}
 
 	/**
 	 * Get a value for the given parameter
 	 * @param string $paramName Parameter name
-	 * @param bool $parseLimit see extractRequestParams()
+	 * @param bool $parseLimit See extractRequestParams()
 	 * @return mixed Parameter value
 	 */
 	protected function getParameter( $paramName, $parseLimit = true ) {
 		$params = $this->getFinalParams();
 		$paramSettings = $params[$paramName];
+
 		return $this->getParameterFromSettings( $paramName, $paramSettings, $parseLimit );
 	}
 
 	/**
 	 * Die if none or more than one of a certain set of parameters is set and not false.
-	 * @param array $params of parameter names
+	 *
+	 * @param array $params User provided set of parameters, as from $this->extractRequestParams()
+	 * @param string $required,... Names of parameters of which exactly one must be set
 	 */
-	public function requireOnlyOneParameter( $params ) {
+	public function requireOnlyOneParameter( $params, $required /*...*/ ) {
 		$required = func_get_args();
 		array_shift( $required );
 		$p = $this->getModulePrefix();
@@ -688,34 +475,24 @@ abstract class ApiBase extends ContextSource {
 			array( $this, "parameterNotEmpty" ) ) ), $required );
 
 		if ( count( $intersection ) > 1 ) {
-			$this->dieUsage( "The parameters {$p}" . implode( ", {$p}", $intersection ) . ' can not be used together', 'invalidparammix' );
+			$this->dieUsage(
+				"The parameters {$p}" . implode( ", {$p}", $intersection ) . ' can not be used together',
+				'invalidparammix' );
 		} elseif ( count( $intersection ) == 0 ) {
-			$this->dieUsage( "One of the parameters {$p}" . implode( ", {$p}", $required ) . ' is required', 'missingparam' );
+			$this->dieUsage(
+				"One of the parameters {$p}" . implode( ", {$p}", $required ) . ' is required',
+				'missingparam'
+			);
 		}
 	}
 
 	/**
-	 * Generates the possible errors requireOnlyOneParameter() can die with
-	 *
-	 * @param $params array
-	 * @return array
-	 */
-	public function getRequireOnlyOneParameterErrorMessages( $params ) {
-		$p = $this->getModulePrefix();
-		$params = implode( ", {$p}", $params );
-
-		return array(
-			array( 'code' => "{$p}missingparam", 'info' => "One of the parameters {$p}{$params} is required" ),
-			array( 'code' => "{$p}invalidparammix", 'info' => "The parameters {$p}{$params} can not be used together" )
-		);
-	}
-
-	/**
 	 * Die if more than one of a certain set of parameters is set and not false.
 	 *
-	 * @param $params array
+	 * @param array $params User provided set of parameters, as from $this->extractRequestParams()
+	 * @param string $required,... Names of parameters of which at most one must be set
 	 */
-	public function requireMaxOneParameter( $params ) {
+	public function requireMaxOneParameter( $params, $required /*...*/ ) {
 		$required = func_get_args();
 		array_shift( $required );
 		$p = $this->getModulePrefix();
@@ -724,27 +501,51 @@ abstract class ApiBase extends ContextSource {
 			array( $this, "parameterNotEmpty" ) ) ), $required );
 
 		if ( count( $intersection ) > 1 ) {
-			$this->dieUsage( "The parameters {$p}" . implode( ", {$p}", $intersection ) . ' can not be used together', 'invalidparammix' );
+			$this->dieUsage(
+				"The parameters {$p}" . implode( ", {$p}", $intersection ) . ' can not be used together',
+				'invalidparammix'
+			);
 		}
 	}
 
 	/**
-	 * Generates the possible error requireMaxOneParameter() can die with
+	 * Die if none of a certain set of parameters is set and not false.
 	 *
-	 * @param $params array
-	 * @return array
+	 * @since 1.23
+	 * @param array $params User provided set of parameters, as from $this->extractRequestParams()
+	 * @param string $required,... Names of parameters of which at least one must be set
 	 */
-	public function getRequireMaxOneParameterErrorMessages( $params ) {
+	public function requireAtLeastOneParameter( $params, $required /*...*/ ) {
+		$required = func_get_args();
+		array_shift( $required );
 		$p = $this->getModulePrefix();
-		$params = implode( ", {$p}", $params );
 
-		return array(
-			array( 'code' => "{$p}invalidparammix", 'info' => "The parameters {$p}{$params} can not be used together" )
+		$intersection = array_intersect(
+			array_keys( array_filter( $params, array( $this, "parameterNotEmpty" ) ) ),
+			$required
 		);
+
+		if ( count( $intersection ) == 0 ) {
+			$this->dieUsage( "At least one of the parameters {$p}" .
+				implode( ", {$p}", $required ) . ' is required', "{$p}missingparam" );
+		}
+	}
+
+	/**
+	 * Callback function used in requireOnlyOneParameter to check whether required parameters are set
+	 *
+	 * @param object $x Parameter to check is not null/false
+	 * @return bool
+	 */
+	private function parameterNotEmpty( $x ) {
+		return !is_null( $x ) && $x !== false;
 	}
 
 	/**
-	 * @param $params array
+	 * Get a WikiPage object from a title or pageid param, if possible.
+	 * Can die, if no param is set or if the title or page id is not valid.
+	 *
+	 * @param array $params
 	 * @param bool|string $load Whether load the object's state from the database:
 	 *        - false: don't load (if the pageid is given, it will still be loaded)
 	 *        - 'fromdb': load from a slave database
@@ -781,44 +582,11 @@ abstract class ApiBase extends ContextSource {
 	}
 
 	/**
-	 * @return array
-	 */
-	public function getTitleOrPageIdErrorMessage() {
-		return array_merge(
-			$this->getRequireOnlyOneParameterErrorMessages( array( 'title', 'pageid' ) ),
-			array(
-				array( 'invalidtitle', 'title' ),
-				array( 'nosuchpageid', 'pageid' ),
-			)
-		);
-	}
-
-	/**
-	 * Callback function used in requireOnlyOneParameter to check whether required parameters are set
-	 *
-	 * @param  $x object Parameter to check is not null/false
-	 * @return bool
-	 */
-	private function parameterNotEmpty( $x ) {
-		return !is_null( $x ) && $x !== false;
-	}
-
-	/**
-	 * @deprecated since 1.17 use MWNamespace::getValidNamespaces()
-	 *
-	 * @return array
-	 */
-	public static function getValidNamespaces() {
-		wfDeprecated( __METHOD__, '1.17' );
-		return MWNamespace::getValidNamespaces();
-	}
-
-	/**
 	 * Return true if we're to watch the page, false if not, null if no change.
 	 * @param string $watchlist Valid values: 'watch', 'unwatch', 'preferences', 'nochange'
-	 * @param $titleObj Title the page under consideration
+	 * @param Title $titleObj The page under consideration
 	 * @param string $userOption The user option to consider when $watchlist=preferences.
-	 * 	If not set will magically default to either watchdefault or watchcreations
+	 *    If not set will use watchdefault always and watchcreations if $titleObj doesn't exist.
 	 * @return bool
 	 */
 	protected function getWatchlistValue( $watchlist, $titleObj, $userOption = null ) {
@@ -837,11 +605,12 @@ abstract class ApiBase extends ContextSource {
 				if ( $userWatching ) {
 					return true;
 				}
-				# If no user option was passed, use watchdefault or watchcreations
+				# If no user option was passed, use watchdefault and watchcreations
 				if ( is_null( $userOption ) ) {
-					$userOption = $titleObj->exists()
-							? 'watchdefault' : 'watchcreations';
+					return $this->getUser()->getBoolOption( 'watchdefault' ) ||
+						$this->getUser()->getBoolOption( 'watchcreations' ) && !$titleObj->exists();
 				}
+
 				# Watch the article based on the user preference
 				return $this->getUser()->getBoolOption( $userOption );
 
@@ -854,27 +623,12 @@ abstract class ApiBase extends ContextSource {
 	}
 
 	/**
-	 * Set a watch (or unwatch) based the based on a watchlist parameter.
-	 * @param string $watch Valid values: 'watch', 'unwatch', 'preferences', 'nochange'
-	 * @param $titleObj Title the article's title to change
-	 * @param string $userOption The user option to consider when $watch=preferences
-	 */
-	protected function setWatch( $watch, $titleObj, $userOption = null ) {
-		$value = $this->getWatchlistValue( $watch, $titleObj, $userOption );
-		if ( $value === null ) {
-			return;
-		}
-
-		WatchAction::doWatchOrUnwatch( $value, $titleObj, $this->getUser() );
-	}
-
-	/**
 	 * Using the settings determine the value for the given parameter
 	 *
-	 * @param string $paramName parameter name
-	 * @param array|mixed $paramSettings default value or an array of settings
+	 * @param string $paramName Parameter name
+	 * @param array|mixed $paramSettings Default value or an array of settings
 	 *  using PARAM_* constants.
-	 * @param $parseLimit Boolean: parse limit?
+	 * @param bool $parseLimit Parse limit?
 	 * @return mixed Parameter value
 	 */
 	protected function getParameterFromSettings( $paramName, $paramSettings, $parseLimit ) {
@@ -889,12 +643,24 @@ abstract class ApiBase extends ContextSource {
 			$deprecated = false;
 			$required = false;
 		} else {
-			$default = isset( $paramSettings[self::PARAM_DFLT] ) ? $paramSettings[self::PARAM_DFLT] : null;
-			$multi = isset( $paramSettings[self::PARAM_ISMULTI] ) ? $paramSettings[self::PARAM_ISMULTI] : false;
-			$type = isset( $paramSettings[self::PARAM_TYPE] ) ? $paramSettings[self::PARAM_TYPE] : null;
-			$dupes = isset( $paramSettings[self::PARAM_ALLOW_DUPLICATES] ) ? $paramSettings[self::PARAM_ALLOW_DUPLICATES] : false;
-			$deprecated = isset( $paramSettings[self::PARAM_DEPRECATED] ) ? $paramSettings[self::PARAM_DEPRECATED] : false;
-			$required = isset( $paramSettings[self::PARAM_REQUIRED] ) ? $paramSettings[self::PARAM_REQUIRED] : false;
+			$default = isset( $paramSettings[self::PARAM_DFLT] )
+				? $paramSettings[self::PARAM_DFLT]
+				: null;
+			$multi = isset( $paramSettings[self::PARAM_ISMULTI] )
+				? $paramSettings[self::PARAM_ISMULTI]
+				: false;
+			$type = isset( $paramSettings[self::PARAM_TYPE] )
+				? $paramSettings[self::PARAM_TYPE]
+				: null;
+			$dupes = isset( $paramSettings[self::PARAM_ALLOW_DUPLICATES] )
+				? $paramSettings[self::PARAM_ALLOW_DUPLICATES]
+				: false;
+			$deprecated = isset( $paramSettings[self::PARAM_DEPRECATED] )
+				? $paramSettings[self::PARAM_DEPRECATED]
+				: false;
+			$required = isset( $paramSettings[self::PARAM_REQUIRED] )
+				? $paramSettings[self::PARAM_REQUIRED]
+				: false;
 
 			// When type is not given, and no choices, the type is the same as $default
 			if ( !isset( $type ) ) {
@@ -909,14 +675,21 @@ abstract class ApiBase extends ContextSource {
 		if ( $type == 'boolean' ) {
 			if ( isset( $default ) && $default !== false ) {
 				// Having a default value of anything other than 'false' is not allowed
-				ApiBase::dieDebug( __METHOD__, "Boolean param $encParamName's default is set to '$default'. Boolean parameters must default to false." );
+				ApiBase::dieDebug(
+					__METHOD__,
+					"Boolean param $encParamName's default is set to '$default'. " .
+						"Boolean parameters must default to false."
+				);
 			}
 
 			$value = $this->getMain()->getCheck( $encParamName );
 		} elseif ( $type == 'upload' ) {
 			if ( isset( $default ) ) {
 				// Having a default value is not allowed
-				ApiBase::dieDebug( __METHOD__, "File upload param $encParamName's default is set to '$default'. File upload parameters may not have a default." );
+				ApiBase::dieDebug(
+					__METHOD__,
+					"File upload param $encParamName's default is set to " .
+						"'$default'. File upload parameters may not have a default." );
 			}
 			if ( $multi ) {
 				ApiBase::dieDebug( __METHOD__, "Multi-values not supported for $encParamName" );
@@ -930,8 +703,8 @@ abstract class ApiBase extends ContextSource {
 				if ( $value !== null ) {
 					$this->dieUsage(
 						"File upload param $encParamName is not a file upload; " .
-						"be sure to use multipart/form-data for your POST and include " .
-						"a filename in the Content-Disposition header.",
+							"be sure to use multipart/form-data for your POST and include " .
+							"a filename in the Content-Disposition header.",
 						"badupload_{$encParamName}"
 					);
 				}
@@ -942,10 +715,18 @@ abstract class ApiBase extends ContextSource {
 			if ( isset( $value ) && $type == 'namespace' ) {
 				$type = MWNamespace::getValidNamespaces();
 			}
+			if ( isset( $value ) && $type == 'submodule' ) {
+				$type = $this->getModuleManager()->getNames( $paramName );
+			}
 		}
 
 		if ( isset( $value ) && ( $multi || is_array( $type ) ) ) {
-			$value = $this->parseMultiValue( $encParamName, $value, $multi, is_array( $type ) ? $type : null );
+			$value = $this->parseMultiValue(
+				$encParamName,
+				$value,
+				$multi,
+				is_array( $type ) ? $type : null
+			);
 		}
 
 		// More validation only when choices were not given
@@ -964,7 +745,7 @@ abstract class ApiBase extends ContextSource {
 						$min = isset( $paramSettings[self::PARAM_MIN] ) ? $paramSettings[self::PARAM_MIN] : null;
 						$max = isset( $paramSettings[self::PARAM_MAX] ) ? $paramSettings[self::PARAM_MAX] : null;
 						$enforceLimits = isset( $paramSettings[self::PARAM_RANGE_ENFORCE] )
-								? $paramSettings[self::PARAM_RANGE_ENFORCE] : false;
+							? $paramSettings[self::PARAM_RANGE_ENFORCE] : false;
 
 						if ( is_array( $value ) ) {
 							$value = array_map( 'intval', $value );
@@ -985,19 +766,32 @@ abstract class ApiBase extends ContextSource {
 							// Don't do any validation whatsoever
 							break;
 						}
-						if ( !isset( $paramSettings[self::PARAM_MAX] ) || !isset( $paramSettings[self::PARAM_MAX2] ) ) {
-							ApiBase::dieDebug( __METHOD__, "MAX1 or MAX2 are not defined for the limit $encParamName" );
+						if ( !isset( $paramSettings[self::PARAM_MAX] )
+							|| !isset( $paramSettings[self::PARAM_MAX2] )
+						) {
+							ApiBase::dieDebug(
+								__METHOD__,
+								"MAX1 or MAX2 are not defined for the limit $encParamName"
+							);
 						}
 						if ( $multi ) {
 							ApiBase::dieDebug( __METHOD__, "Multi-values not supported for $encParamName" );
 						}
 						$min = isset( $paramSettings[self::PARAM_MIN] ) ? $paramSettings[self::PARAM_MIN] : 0;
 						if ( $value == 'max' ) {
-							$value = $this->getMain()->canApiHighLimits() ? $paramSettings[self::PARAM_MAX2] : $paramSettings[self::PARAM_MAX];
+							$value = $this->getMain()->canApiHighLimits()
+								? $paramSettings[self::PARAM_MAX2]
+								: $paramSettings[self::PARAM_MAX];
 							$this->getResult()->setParsedLimit( $this->getModuleName(), $value );
 						} else {
 							$value = intval( $value );
-							$this->validateLimit( $paramName, $value, $min, $paramSettings[self::PARAM_MAX], $paramSettings[self::PARAM_MAX2] );
+							$this->validateLimit(
+								$paramName,
+								$value,
+								$min,
+								$paramSettings[self::PARAM_MAX],
+								$paramSettings[self::PARAM_MAX2]
+							);
 						}
 						break;
 					case 'boolean':
@@ -1052,25 +846,28 @@ abstract class ApiBase extends ContextSource {
 	 *
 	 * @param string $valueName The name of the parameter (for error
 	 *  reporting)
-	 * @param $value mixed The value being parsed
+	 * @param mixed $value The value being parsed
 	 * @param bool $allowMultiple Can $value contain more than one value
 	 *  separated by '|'?
-	 * @param $allowedValues mixed An array of values to check against. If
+	 * @param string[]|null $allowedValues An array of values to check against. If
 	 *  null, all values are accepted.
-	 * @return mixed (allowMultiple ? an_array_of_values : a_single_value)
+	 * @return string|string[] (allowMultiple ? an_array_of_values : a_single_value)
 	 */
 	protected function parseMultiValue( $valueName, $value, $allowMultiple, $allowedValues ) {
 		if ( trim( $value ) === '' && $allowMultiple ) {
 			return array();
 		}
 
-		// This is a bit awkward, but we want to avoid calling canApiHighLimits() because it unstubs $wgUser
+		// This is a bit awkward, but we want to avoid calling canApiHighLimits()
+		// because it unstubs $wgUser
 		$valuesList = explode( '|', $value, self::LIMIT_SML2 + 1 );
-		$sizeLimit = count( $valuesList ) > self::LIMIT_SML1 && $this->mMainModule->canApiHighLimits() ?
-				self::LIMIT_SML2 : self::LIMIT_SML1;
+		$sizeLimit = count( $valuesList ) > self::LIMIT_SML1 && $this->mMainModule->canApiHighLimits()
+			? self::LIMIT_SML2
+			: self::LIMIT_SML1;
 
 		if ( self::truncateArray( $valuesList, $sizeLimit ) ) {
-			$this->setWarning( "Too many values supplied for parameter '$valueName': the limit is $sizeLimit" );
+			$this->setWarning( "Too many values supplied for parameter '$valueName': " .
+				"the limit is $sizeLimit" );
 		}
 
 		if ( !$allowMultiple && count( $valuesList ) != 1 ) {
@@ -1079,8 +876,13 @@ abstract class ApiBase extends ContextSource {
 				return $value;
 			}
 
-			$possibleValues = is_array( $allowedValues ) ? "of '" . implode( "', '", $allowedValues ) . "'" : '';
-			$this->dieUsage( "Only one $possibleValues is allowed for parameter '$valueName'", "multival_$valueName" );
+			$possibleValues = is_array( $allowedValues )
+				? "of '" . implode( "', '", $allowedValues ) . "'"
+				: '';
+			$this->dieUsage(
+				"Only one $possibleValues is allowed for parameter '$valueName'",
+				"multival_$valueName"
+			);
 		}
 
 		if ( is_array( $allowedValues ) ) {
@@ -1092,7 +894,10 @@ abstract class ApiBase extends ContextSource {
 					$vals = implode( ", ", $unknown );
 					$this->setWarning( "Unrecognized value$s for parameter '$valueName': $vals" );
 				} else {
-					$this->dieUsage( "Unrecognized value for parameter '$valueName': {$valuesList[0]}", "unknown_$valueName" );
+					$this->dieUsage(
+						"Unrecognized value for parameter '$valueName': {$valuesList[0]}",
+						"unknown_$valueName"
+					);
 				}
 			}
 			// Now throw them out
@@ -1110,9 +915,9 @@ abstract class ApiBase extends ContextSource {
 	 * @param int|null $min Minimum value
 	 * @param int|null $max Maximum value for users
 	 * @param int $botMax Maximum value for sysops/bots
-	 * @param $enforceLimits Boolean Whether to enforce (die) if value is outside limits
+	 * @param bool $enforceLimits Whether to enforce (die) if value is outside limits
 	 */
-	function validateLimit( $paramName, &$value, $min, $max, $botMax = null, $enforceLimits = false ) {
+	protected function validateLimit( $paramName, &$value, $min, $max, $botMax = null, $enforceLimits = false ) {
 		if ( !is_null( $min ) && $value < $min ) {
 
 			$msg = $this->encodeParamName( $paramName ) . " may not be less than $min (set to $value)";
@@ -1120,7 +925,8 @@ abstract class ApiBase extends ContextSource {
 			$value = $min;
 		}
 
-		// Minimum is always validated, whereas maximum is checked only if not running in internal call mode
+		// Minimum is always validated, whereas maximum is checked only if not
+		// running in internal call mode
 		if ( $this->getMain()->isInternalMode() ) {
 			return;
 		}
@@ -1130,7 +936,8 @@ abstract class ApiBase extends ContextSource {
 		if ( !is_null( $max ) && $value > $max ) {
 			if ( !is_null( $botMax ) && $this->getMain()->canApiHighLimits() ) {
 				if ( $value > $botMax ) {
-					$msg = $this->encodeParamName( $paramName ) . " may not be over $botMax (set to $value) for bots or sysops";
+					$msg = $this->encodeParamName( $paramName ) .
+						" may not be over $botMax (set to $value) for bots or sysops";
 					$this->warnOrDie( $msg, $enforceLimits );
 					$value = $botMax;
 				}
@@ -1148,15 +955,57 @@ abstract class ApiBase extends ContextSource {
 	 * @param string $encParamName Parameter name
 	 * @return string Validated and normalized parameter
 	 */
-	function validateTimestamp( $value, $encParamName ) {
+	protected function validateTimestamp( $value, $encParamName ) {
 		$unixTimestamp = wfTimestamp( TS_UNIX, $value );
 		if ( $unixTimestamp === false ) {
-			$this->dieUsage( "Invalid value '$value' for timestamp parameter $encParamName", "badtimestamp_{$encParamName}" );
+			$this->dieUsage(
+				"Invalid value '$value' for timestamp parameter $encParamName",
+				"badtimestamp_{$encParamName}"
+			);
 		}
+
 		return wfTimestamp( TS_MW, $unixTimestamp );
 	}
 
 	/**
+	 * Validate the supplied token.
+	 *
+	 * @since 1.24
+	 * @param string $token Supplied token
+	 * @param array $params All supplied parameters for the module
+	 * @return bool
+	 */
+	public final function validateToken( $token, array $params ) {
+		$tokenType = $this->needsToken();
+		$salts = ApiQueryTokens::getTokenTypeSalts();
+		if ( !isset( $salts[$tokenType] ) ) {
+			throw new MWException(
+				"Module '{$this->getModuleName()}' tried to use token type '$tokenType' " .
+					'without registering it'
+			);
+		}
+
+		if ( $this->getUser()->matchEditToken(
+			$token,
+			$salts[$tokenType],
+			$this->getRequest()
+		) ) {
+			return true;
+		}
+
+		$webUiSalt = $this->getWebUITokenSalt( $params );
+		if ( $webUiSalt !== null && $this->getUser()->matchEditToken(
+			$token,
+			$webUiSalt,
+			$this->getRequest()
+		) ) {
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
 	 * Validate and normalize of parameters of type 'user'
 	 * @param string $value Parameter value
 	 * @param string $encParamName Parameter name
@@ -1165,23 +1014,35 @@ abstract class ApiBase extends ContextSource {
 	private function validateUser( $value, $encParamName ) {
 		$title = Title::makeTitleSafe( NS_USER, $value );
 		if ( $title === null ) {
-			$this->dieUsage( "Invalid value '$value' for user parameter $encParamName", "baduser_{$encParamName}" );
+			$this->dieUsage(
+				"Invalid value '$value' for user parameter $encParamName",
+				"baduser_{$encParamName}"
+			);
 		}
+
 		return $title->getText();
 	}
 
+	/**@}*/
+
+	/************************************************************************//**
+	 * @name   Utility methods
+	 * @{
+	 */
+
 	/**
-	 * Adds a warning to the output, else dies
-	 *
-	 * @param  $msg String Message to show as a warning, or error message if dying
-	 * @param  $enforceLimits Boolean Whether this is an enforce (die)
+	 * Set a watch (or unwatch) based the based on a watchlist parameter.
+	 * @param string $watch Valid values: 'watch', 'unwatch', 'preferences', 'nochange'
+	 * @param Title $titleObj The article's title to change
+	 * @param string $userOption The user option to consider when $watch=preferences
 	 */
-	private function warnOrDie( $msg, $enforceLimits = false ) {
-		if ( $enforceLimits ) {
-			$this->dieUsage( $msg, 'integeroutofrange' );
-		} else {
-			$this->setWarning( $msg );
+	protected function setWatch( $watch, $titleObj, $userOption = null ) {
+		$value = $this->getWatchlistValue( $watch, $titleObj, $userOption );
+		if ( $value === null ) {
+			return;
 		}
+
+		WatchAction::doWatchOrUnwatch( $value, $titleObj, $this->getUser() );
 	}
 
 	/**
@@ -1196,10 +1057,96 @@ abstract class ApiBase extends ContextSource {
 			array_pop( $arr );
 			$modified = true;
 		}
+
 		return $modified;
 	}
 
 	/**
+	 * Gets the user for whom to get the watchlist
+	 *
+	 * @param array $params
+	 * @return User
+	 */
+	public function getWatchlistUser( $params ) {
+		if ( !is_null( $params['owner'] ) && !is_null( $params['token'] ) ) {
+			$user = User::newFromName( $params['owner'], false );
+			if ( !( $user && $user->getId() ) ) {
+				$this->dieUsage( 'Specified user does not exist', 'bad_wlowner' );
+			}
+			$token = $user->getOption( 'watchlisttoken' );
+			if ( $token == '' || $token != $params['token'] ) {
+				$this->dieUsage(
+					'Incorrect watchlist token provided -- please set a correct token in Special:Preferences',
+					'bad_wltoken'
+				);
+			}
+		} else {
+			if ( !$this->getUser()->isLoggedIn() ) {
+				$this->dieUsage( 'You must be logged-in to have a watchlist', 'notloggedin' );
+			}
+			if ( !$this->getUser()->isAllowed( 'viewmywatchlist' ) ) {
+				$this->dieUsage( 'You don\'t have permission to view your watchlist', 'permissiondenied' );
+			}
+			$user = $this->getUser();
+		}
+
+		return $user;
+	}
+
+	/**@}*/
+
+	/************************************************************************//**
+	 * @name   Warning and error reporting
+	 * @{
+	 */
+
+	/**
+	 * Set warning section for this module. Users should monitor this
+	 * section to notice any changes in API. Multiple calls to this
+	 * function will result in the warning messages being separated by
+	 * newlines
+	 * @param string $warning Warning message
+	 */
+	public function setWarning( $warning ) {
+		$result = $this->getResult();
+		$data = $result->getData();
+		$moduleName = $this->getModuleName();
+		if ( isset( $data['warnings'][$moduleName] ) ) {
+			// Don't add duplicate warnings
+			$oldWarning = $data['warnings'][$moduleName]['*'];
+			$warnPos = strpos( $oldWarning, $warning );
+			// If $warning was found in $oldWarning, check if it starts at 0 or after "\n"
+			if ( $warnPos !== false && ( $warnPos === 0 || $oldWarning[$warnPos - 1] === "\n" ) ) {
+				// Check if $warning is followed by "\n" or the end of the $oldWarning
+				$warnPos += strlen( $warning );
+				if ( strlen( $oldWarning ) <= $warnPos || $oldWarning[$warnPos] === "\n" ) {
+					return;
+				}
+			}
+			// If there is a warning already, append it to the existing one
+			$warning = "$oldWarning\n$warning";
+		}
+		$msg = array();
+		ApiResult::setContent( $msg, $warning );
+		$result->addValue( 'warnings', $moduleName,
+			$msg, ApiResult::OVERRIDE | ApiResult::ADD_ON_TOP | ApiResult::NO_SIZE_CHECK );
+	}
+
+	/**
+	 * Adds a warning to the output, else dies
+	 *
+	 * @param string $msg Message to show as a warning, or error message if dying
+	 * @param bool $enforceLimits Whether this is an enforce (die)
+	 */
+	private function warnOrDie( $msg, $enforceLimits = false ) {
+		if ( $enforceLimits ) {
+			$this->dieUsage( $msg, 'integeroutofrange' );
+		}
+
+		$this->setWarning( $msg );
+	}
+
+	/**
 	 * Throw a UsageException, which will (if uncaught) call the main module's
 	 * error handler and die with an error message.
 	 *
@@ -1213,17 +1160,22 @@ abstract class ApiBase extends ContextSource {
 	 */
 	public function dieUsage( $description, $errorCode, $httpRespCode = 0, $extradata = null ) {
 		Profiler::instance()->close();
-		throw new UsageException( $description, $this->encodeParamName( $errorCode ), $httpRespCode, $extradata );
+		throw new UsageException(
+			$description,
+			$this->encodeParamName( $errorCode ),
+			$httpRespCode,
+			$extradata
+		);
 	}
 
 	/**
-	 * Throw a UsageException based on the errors in the Status object.
+	 * Get error (as code, string) from a Status object.
 	 *
-	 * @since 1.22
-	 * @param Status $status Status object
-	 * @throws UsageException
+	 * @since 1.23
+	 * @param Status $status
+	 * @return array Array of code and error string
 	 */
-	public function dieStatus( $status ) {
+	public function getErrorFromStatus( $status ) {
 		if ( $status->isGood() ) {
 			throw new MWException( 'Successful status passed to ApiBase::dieStatus' );
 		}
@@ -1248,13 +1200,28 @@ abstract class ApiBase extends ContextSource {
 			$msg = wfMessage( $code, $errors[0] );
 		}
 		if ( isset( ApiBase::$messageMap[$code] ) ) {
-			// Translate message to code, for backwards compatability
+			// Translate message to code, for backwards compatibility
 			$code = ApiBase::$messageMap[$code]['code'];
 		}
-		$this->dieUsage( $msg->inLanguage( 'en' )->useDatabase( false )->plain(), $code );
+
+		return array( $code, $msg->inLanguage( 'en' )->useDatabase( false )->plain() );
 	}
 
 	/**
+	 * Throw a UsageException based on the errors in the Status object.
+	 *
+	 * @since 1.22
+	 * @param Status $status
+	 * @throws MWException
+	 */
+	public function dieStatus( $status ) {
+
+		list( $code, $msg ) = $this->getErrorFromStatus( $status );
+		$this->dieUsage( $msg, $code );
+	}
+
+	// @codingStandardsIgnoreStart Allow long lines. Cannot split these.
+	/**
 	 * Array that maps message keys to error messages. $1 and friends are replaced.
 	 */
 	public static $messageMap = array(
@@ -1263,74 +1230,243 @@ abstract class ApiBase extends ContextSource {
 		'unknownerror-nocode' => array( 'code' => 'unknownerror', 'info' => 'Unknown error' ),
 
 		// Messages from Title::getUserPermissionsErrors()
-		'ns-specialprotected' => array( 'code' => 'unsupportednamespace', 'info' => "Pages in the Special namespace can't be edited" ),
-		'protectedinterface' => array( 'code' => 'protectednamespace-interface', 'info' => "You're not allowed to edit interface messages" ),
-		'namespaceprotected' => array( 'code' => 'protectednamespace', 'info' => "You're not allowed to edit pages in the \"\$1\" namespace" ),
-		'customcssprotected' => array( 'code' => 'customcssprotected', 'info' => "You're not allowed to edit custom CSS pages" ),
-		'customjsprotected' => array( 'code' => 'customjsprotected', 'info' => "You're not allowed to edit custom JavaScript pages" ),
-		'cascadeprotected' => array( 'code' => 'cascadeprotected', 'info' => "The page you're trying to edit is protected because it's included in a cascade-protected page" ),
-		'protectedpagetext' => array( 'code' => 'protectedpage', 'info' => "The \"\$1\" right is required to edit this page" ),
-		'protect-cantedit' => array( 'code' => 'cantedit', 'info' => "You can't protect this page because you can't edit it" ),
-		'badaccess-group0' => array( 'code' => 'permissiondenied', 'info' => "Permission denied" ), // Generic permission denied message
-		'badaccess-groups' => array( 'code' => 'permissiondenied', 'info' => "Permission denied" ),
-		'titleprotected' => array( 'code' => 'protectedtitle', 'info' => "This title has been protected from creation" ),
-		'nocreate-loggedin' => array( 'code' => 'cantcreate', 'info' => "You don't have permission to create new pages" ),
-		'nocreatetext' => array( 'code' => 'cantcreate-anon', 'info' => "Anonymous users can't create new pages" ),
-		'movenologintext' => array( 'code' => 'cantmove-anon', 'info' => "Anonymous users can't move pages" ),
-		'movenotallowed' => array( 'code' => 'cantmove', 'info' => "You don't have permission to move pages" ),
-		'confirmedittext' => array( 'code' => 'confirmemail', 'info' => "You must confirm your email address before you can edit" ),
-		'blockedtext' => array( 'code' => 'blocked', 'info' => "You have been blocked from editing" ),
-		'autoblockedtext' => array( 'code' => 'autoblocked', 'info' => "Your IP address has been blocked automatically, because it was used by a blocked user" ),
+		'ns-specialprotected' => array(
+			'code' => 'unsupportednamespace',
+			'info' => "Pages in the Special namespace can't be edited"
+		),
+		'protectedinterface' => array(
+			'code' => 'protectednamespace-interface',
+			'info' => "You're not allowed to edit interface messages"
+		),
+		'namespaceprotected' => array(
+			'code' => 'protectednamespace',
+			'info' => "You're not allowed to edit pages in the \"\$1\" namespace"
+		),
+		'customcssprotected' => array(
+			'code' => 'customcssprotected',
+			'info' => "You're not allowed to edit custom CSS pages"
+		),
+		'customjsprotected' => array(
+			'code' => 'customjsprotected',
+			'info' => "You're not allowed to edit custom JavaScript pages"
+		),
+		'cascadeprotected' => array(
+			'code' => 'cascadeprotected',
+			'info' => "The page you're trying to edit is protected because it's included in a cascade-protected page"
+		),
+		'protectedpagetext' => array(
+			'code' => 'protectedpage',
+			'info' => "The \"\$1\" right is required to edit this page"
+		),
+		'protect-cantedit' => array(
+			'code' => 'cantedit',
+			'info' => "You can't protect this page because you can't edit it"
+		),
+		'deleteprotected' => array(
+			'code' => 'cantedit',
+			'info' => "You can't delete this page because it has been protected"
+		),
+		'badaccess-group0' => array(
+			'code' => 'permissiondenied',
+			'info' => "Permission denied"
+		), // Generic permission denied message
+		'badaccess-groups' => array(
+			'code' => 'permissiondenied',
+			'info' => "Permission denied"
+		),
+		'titleprotected' => array(
+			'code' => 'protectedtitle',
+			'info' => "This title has been protected from creation"
+		),
+		'nocreate-loggedin' => array(
+			'code' => 'cantcreate',
+			'info' => "You don't have permission to create new pages"
+		),
+		'nocreatetext' => array(
+			'code' => 'cantcreate-anon',
+			'info' => "Anonymous users can't create new pages"
+		),
+		'movenologintext' => array(
+			'code' => 'cantmove-anon',
+			'info' => "Anonymous users can't move pages"
+		),
+		'movenotallowed' => array(
+			'code' => 'cantmove',
+			'info' => "You don't have permission to move pages"
+		),
+		'confirmedittext' => array(
+			'code' => 'confirmemail',
+			'info' => "You must confirm your email address before you can edit"
+		),
+		'blockedtext' => array(
+			'code' => 'blocked',
+			'info' => "You have been blocked from editing"
+		),
+		'autoblockedtext' => array(
+			'code' => 'autoblocked',
+			'info' => "Your IP address has been blocked automatically, because it was used by a blocked user"
+		),
 
 		// Miscellaneous interface messages
-		'actionthrottledtext' => array( 'code' => 'ratelimited', 'info' => "You've exceeded your rate limit. Please wait some time and try again" ),
-		'alreadyrolled' => array( 'code' => 'alreadyrolled', 'info' => "The page you tried to rollback was already rolled back" ),
-		'cantrollback' => array( 'code' => 'onlyauthor', 'info' => "The page you tried to rollback only has one author" ),
-		'readonlytext' => array( 'code' => 'readonly', 'info' => "The wiki is currently in read-only mode" ),
-		'sessionfailure' => array( 'code' => 'badtoken', 'info' => "Invalid token" ),
-		'cannotdelete' => array( 'code' => 'cantdelete', 'info' => "Couldn't delete \"\$1\". Maybe it was deleted already by someone else" ),
-		'notanarticle' => array( 'code' => 'missingtitle', 'info' => "The page you requested doesn't exist" ),
-		'selfmove' => array( 'code' => 'selfmove', 'info' => "Can't move a page to itself" ),
-		'immobile_namespace' => array( 'code' => 'immobilenamespace', 'info' => "You tried to move pages from or to a namespace that is protected from moving" ),
-		'articleexists' => array( 'code' => 'articleexists', 'info' => "The destination article already exists and is not a redirect to the source article" ),
-		'protectedpage' => array( 'code' => 'protectedpage', 'info' => "You don't have permission to perform this move" ),
-		'hookaborted' => array( 'code' => 'hookaborted', 'info' => "The modification you tried to make was aborted by an extension hook" ),
-		'cantmove-titleprotected' => array( 'code' => 'protectedtitle', 'info' => "The destination article has been protected from creation" ),
-		'imagenocrossnamespace' => array( 'code' => 'nonfilenamespace', 'info' => "Can't move a file to a non-file namespace" ),
-		'imagetypemismatch' => array( 'code' => 'filetypemismatch', 'info' => "The new file extension doesn't match its type" ),
+		'actionthrottledtext' => array(
+			'code' => 'ratelimited',
+			'info' => "You've exceeded your rate limit. Please wait some time and try again"
+		),
+		'alreadyrolled' => array(
+			'code' => 'alreadyrolled',
+			'info' => "The page you tried to rollback was already rolled back"
+		),
+		'cantrollback' => array(
+			'code' => 'onlyauthor',
+			'info' => "The page you tried to rollback only has one author"
+		),
+		'readonlytext' => array(
+			'code' => 'readonly',
+			'info' => "The wiki is currently in read-only mode"
+		),
+		'sessionfailure' => array(
+			'code' => 'badtoken',
+			'info' => "Invalid token" ),
+		'cannotdelete' => array(
+			'code' => 'cantdelete',
+			'info' => "Couldn't delete \"\$1\". Maybe it was deleted already by someone else"
+		),
+		'notanarticle' => array(
+			'code' => 'missingtitle',
+			'info' => "The page you requested doesn't exist"
+		),
+		'selfmove' => array( 'code' => 'selfmove', 'info' => "Can't move a page to itself"
+		),
+		'immobile_namespace' => array(
+			'code' => 'immobilenamespace',
+			'info' => "You tried to move pages from or to a namespace that is protected from moving"
+		),
+		'articleexists' => array(
+			'code' => 'articleexists',
+			'info' => "The destination article already exists and is not a redirect to the source article"
+		),
+		'protectedpage' => array(
+			'code' => 'protectedpage',
+			'info' => "You don't have permission to perform this move"
+		),
+		'hookaborted' => array(
+			'code' => 'hookaborted',
+			'info' => "The modification you tried to make was aborted by an extension hook"
+		),
+		'cantmove-titleprotected' => array(
+			'code' => 'protectedtitle',
+			'info' => "The destination article has been protected from creation"
+		),
+		'imagenocrossnamespace' => array(
+			'code' => 'nonfilenamespace',
+			'info' => "Can't move a file to a non-file namespace"
+		),
+		'imagetypemismatch' => array(
+			'code' => 'filetypemismatch',
+			'info' => "The new file extension doesn't match its type"
+		),
 		// 'badarticleerror' => shouldn't happen
 		// 'badtitletext' => shouldn't happen
 		'ip_range_invalid' => array( 'code' => 'invalidrange', 'info' => "Invalid IP range" ),
-		'range_block_disabled' => array( 'code' => 'rangedisabled', 'info' => "Blocking IP ranges has been disabled" ),
-		'nosuchusershort' => array( 'code' => 'nosuchuser', 'info' => "The user you specified doesn't exist" ),
+		'range_block_disabled' => array(
+			'code' => 'rangedisabled',
+			'info' => "Blocking IP ranges has been disabled"
+		),
+		'nosuchusershort' => array(
+			'code' => 'nosuchuser',
+			'info' => "The user you specified doesn't exist"
+		),
 		'badipaddress' => array( 'code' => 'invalidip', 'info' => "Invalid IP address specified" ),
 		'ipb_expiry_invalid' => array( 'code' => 'invalidexpiry', 'info' => "Invalid expiry time" ),
-		'ipb_already_blocked' => array( 'code' => 'alreadyblocked', 'info' => "The user you tried to block was already blocked" ),
-		'ipb_blocked_as_range' => array( 'code' => 'blockedasrange', 'info' => "IP address \"\$1\" was blocked as part of range \"\$2\". You can't unblock the IP individually, but you can unblock the range as a whole." ),
-		'ipb_cant_unblock' => array( 'code' => 'cantunblock', 'info' => "The block you specified was not found. It may have been unblocked already" ),
-		'mailnologin' => array( 'code' => 'cantsend', 'info' => "You are not logged in, you do not have a confirmed email address, or you are not allowed to send email to other users, so you cannot send email" ),
-		'ipbblocked' => array( 'code' => 'ipbblocked', 'info' => 'You cannot block or unblock users while you are yourself blocked' ),
-		'ipbnounblockself' => array( 'code' => 'ipbnounblockself', 'info' => 'You are not allowed to unblock yourself' ),
-		'usermaildisabled' => array( 'code' => 'usermaildisabled', 'info' => "User email has been disabled" ),
-		'blockedemailuser' => array( 'code' => 'blockedfrommail', 'info' => "You have been blocked from sending email" ),
-		'notarget' => array( 'code' => 'notarget', 'info' => "You have not specified a valid target for this action" ),
-		'noemail' => array( 'code' => 'noemail', 'info' => "The user has not specified a valid email address, or has chosen not to receive email from other users" ),
-		'rcpatroldisabled' => array( 'code' => 'patroldisabled', 'info' => "Patrolling is disabled on this wiki" ),
-		'markedaspatrollederror-noautopatrol' => array( 'code' => 'noautopatrol', 'info' => "You don't have permission to patrol your own changes" ),
-		'delete-toobig' => array( 'code' => 'bigdelete', 'info' => "You can't delete this page because it has more than \$1 revisions" ),
-		'movenotallowedfile' => array( 'code' => 'cantmovefile', 'info' => "You don't have permission to move files" ),
-		'userrights-no-interwiki' => array( 'code' => 'nointerwikiuserrights', 'info' => "You don't have permission to change user rights on other wikis" ),
-		'userrights-nodatabase' => array( 'code' => 'nosuchdatabase', 'info' => "Database \"\$1\" does not exist or is not local" ),
+		'ipb_already_blocked' => array(
+			'code' => 'alreadyblocked',
+			'info' => "The user you tried to block was already blocked"
+		),
+		'ipb_blocked_as_range' => array(
+			'code' => 'blockedasrange',
+			'info' => "IP address \"\$1\" was blocked as part of range \"\$2\". You can't unblock the IP individually, but you can unblock the range as a whole."
+		),
+		'ipb_cant_unblock' => array(
+			'code' => 'cantunblock',
+			'info' => "The block you specified was not found. It may have been unblocked already"
+		),
+		'mailnologin' => array(
+			'code' => 'cantsend',
+			'info' => "You are not logged in, you do not have a confirmed email address, or you are not allowed to send email to other users, so you cannot send email"
+		),
+		'ipbblocked' => array(
+			'code' => 'ipbblocked',
+			'info' => 'You cannot block or unblock users while you are yourself blocked'
+		),
+		'ipbnounblockself' => array(
+			'code' => 'ipbnounblockself',
+			'info' => 'You are not allowed to unblock yourself'
+		),
+		'usermaildisabled' => array(
+			'code' => 'usermaildisabled',
+			'info' => "User email has been disabled"
+		),
+		'blockedemailuser' => array(
+			'code' => 'blockedfrommail',
+			'info' => "You have been blocked from sending email"
+		),
+		'notarget' => array(
+			'code' => 'notarget',
+			'info' => "You have not specified a valid target for this action"
+		),
+		'noemail' => array(
+			'code' => 'noemail',
+			'info' => "The user has not specified a valid email address, or has chosen not to receive email from other users"
+		),
+		'rcpatroldisabled' => array(
+			'code' => 'patroldisabled',
+			'info' => "Patrolling is disabled on this wiki"
+		),
+		'markedaspatrollederror-noautopatrol' => array(
+			'code' => 'noautopatrol',
+			'info' => "You don't have permission to patrol your own changes"
+		),
+		'delete-toobig' => array(
+			'code' => 'bigdelete',
+			'info' => "You can't delete this page because it has more than \$1 revisions"
+		),
+		'movenotallowedfile' => array(
+			'code' => 'cantmovefile',
+			'info' => "You don't have permission to move files"
+		),
+		'userrights-no-interwiki' => array(
+			'code' => 'nointerwikiuserrights',
+			'info' => "You don't have permission to change user rights on other wikis"
+		),
+		'userrights-nodatabase' => array(
+			'code' => 'nosuchdatabase',
+			'info' => "Database \"\$1\" does not exist or is not local"
+		),
 		'nouserspecified' => array( 'code' => 'invaliduser', 'info' => "Invalid username \"\$1\"" ),
 		'noname' => array( 'code' => 'invaliduser', 'info' => "Invalid username \"\$1\"" ),
 		'summaryrequired' => array( 'code' => 'summaryrequired', 'info' => 'Summary required' ),
-		'import-rootpage-invalid' => array( 'code' => 'import-rootpage-invalid', 'info' => 'Root page is an invalid title' ),
-		'import-rootpage-nosubpage' => array( 'code' => 'import-rootpage-nosubpage', 'info' => 'Namespace "$1" of the root page does not allow subpages' ),
+		'import-rootpage-invalid' => array(
+			'code' => 'import-rootpage-invalid',
+			'info' => 'Root page is an invalid title'
+		),
+		'import-rootpage-nosubpage' => array(
+			'code' => 'import-rootpage-nosubpage',
+			'info' => 'Namespace "$1" of the root page does not allow subpages'
+		),
 
 		// API-specific messages
-		'readrequired' => array( 'code' => 'readapidenied', 'info' => "You need read permission to use this module" ),
-		'writedisabled' => array( 'code' => 'noapiwrite', 'info' => "Editing of this wiki through the API is disabled. Make sure the \$wgEnableWriteAPI=true; statement is included in the wiki's LocalSettings.php file" ),
-		'writerequired' => array( 'code' => 'writeapidenied', 'info' => "You're not allowed to edit this wiki through the API" ),
+		'readrequired' => array(
+			'code' => 'readapidenied',
+			'info' => "You need read permission to use this module"
+		),
+		'writedisabled' => array(
+			'code' => 'noapiwrite',
+			'info' => "Editing of this wiki through the API is disabled. Make sure the \$wgEnableWriteAPI=true; statement is included in the wiki's LocalSettings.php file"
+		),
+		'writerequired' => array(
+			'code' => 'writeapidenied',
+			'info' => "You're not allowed to edit this wiki through the API"
+		),
 		'missingparam' => array( 'code' => 'no$1', 'info' => "The \$1 parameter must be set" ),
 		'invalidtitle' => array( 'code' => 'invalidtitle', 'info' => "Bad title \"\$1\"" ),
 		'nosuchpageid' => array( 'code' => 'nosuchpageid', 'info' => "There is no page with ID \$1" ),
@@ -1339,81 +1475,253 @@ abstract class ApiBase extends ContextSource {
 		'invaliduser' => array( 'code' => 'invaliduser', 'info' => "Invalid username \"\$1\"" ),
 		'invalidexpiry' => array( 'code' => 'invalidexpiry', 'info' => "Invalid expiry time \"\$1\"" ),
 		'pastexpiry' => array( 'code' => 'pastexpiry', 'info' => "Expiry time \"\$1\" is in the past" ),
-		'create-titleexists' => array( 'code' => 'create-titleexists', 'info' => "Existing titles can't be protected with 'create'" ),
-		'missingtitle-createonly' => array( 'code' => 'missingtitle-createonly', 'info' => "Missing titles can only be protected with 'create'" ),
-		'cantblock' => array( 'code' => 'cantblock', 'info' => "You don't have permission to block users" ),
-		'canthide' => array( 'code' => 'canthide', 'info' => "You don't have permission to hide user names from the block log" ),
-		'cantblock-email' => array( 'code' => 'cantblock-email', 'info' => "You don't have permission to block users from sending email through the wiki" ),
-		'unblock-notarget' => array( 'code' => 'notarget', 'info' => "Either the id or the user parameter must be set" ),
-		'unblock-idanduser' => array( 'code' => 'idanduser', 'info' => "The id and user parameters can't be used together" ),
-		'cantunblock' => array( 'code' => 'permissiondenied', 'info' => "You don't have permission to unblock users" ),
-		'cannotundelete' => array( 'code' => 'cantundelete', 'info' => "Couldn't undelete: the requested revisions may not exist, or may have been undeleted already" ),
-		'permdenied-undelete' => array( 'code' => 'permissiondenied', 'info' => "You don't have permission to restore deleted revisions" ),
-		'createonly-exists' => array( 'code' => 'articleexists', 'info' => "The article you tried to create has been created already" ),
-		'nocreate-missing' => array( 'code' => 'missingtitle', 'info' => "The article you tried to edit doesn't exist" ),
-		'cantchangecontentmodel' => array( 'code' => 'cantchangecontentmodel', 'info' => "You don't have permission to change the content model of a page" ),
-		'nosuchrcid' => array( 'code' => 'nosuchrcid', 'info' => "There is no change with rcid \"\$1\"" ),
-		'protect-invalidaction' => array( 'code' => 'protect-invalidaction', 'info' => "Invalid protection type \"\$1\"" ),
-		'protect-invalidlevel' => array( 'code' => 'protect-invalidlevel', 'info' => "Invalid protection level \"\$1\"" ),
-		'toofewexpiries' => array( 'code' => 'toofewexpiries', 'info' => "\$1 expiry timestamps were provided where \$2 were needed" ),
-		'cantimport' => array( 'code' => 'cantimport', 'info' => "You don't have permission to import pages" ),
-		'cantimport-upload' => array( 'code' => 'cantimport-upload', 'info' => "You don't have permission to import uploaded pages" ),
+		'create-titleexists' => array(
+			'code' => 'create-titleexists',
+			'info' => "Existing titles can't be protected with 'create'"
+		),
+		'missingtitle-createonly' => array(
+			'code' => 'missingtitle-createonly',
+			'info' => "Missing titles can only be protected with 'create'"
+		),
+		'cantblock' => array( 'code' => 'cantblock',
+			'info' => "You don't have permission to block users"
+		),
+		'canthide' => array(
+			'code' => 'canthide',
+			'info' => "You don't have permission to hide user names from the block log"
+		),
+		'cantblock-email' => array(
+			'code' => 'cantblock-email',
+			'info' => "You don't have permission to block users from sending email through the wiki"
+		),
+		'unblock-notarget' => array(
+			'code' => 'notarget',
+			'info' => "Either the id or the user parameter must be set"
+		),
+		'unblock-idanduser' => array(
+			'code' => 'idanduser',
+			'info' => "The id and user parameters can't be used together"
+		),
+		'cantunblock' => array(
+			'code' => 'permissiondenied',
+			'info' => "You don't have permission to unblock users"
+		),
+		'cannotundelete' => array(
+			'code' => 'cantundelete',
+			'info' => "Couldn't undelete: the requested revisions may not exist, or may have been undeleted already"
+		),
+		'permdenied-undelete' => array(
+			'code' => 'permissiondenied',
+			'info' => "You don't have permission to restore deleted revisions"
+		),
+		'createonly-exists' => array(
+			'code' => 'articleexists',
+			'info' => "The article you tried to create has been created already"
+		),
+		'nocreate-missing' => array(
+			'code' => 'missingtitle',
+			'info' => "The article you tried to edit doesn't exist"
+		),
+		'cantchangecontentmodel' => array(
+			'code' => 'cantchangecontentmodel',
+			'info' => "You don't have permission to change the content model of a page"
+		),
+		'nosuchrcid' => array(
+			'code' => 'nosuchrcid',
+			'info' => "There is no change with rcid \"\$1\""
+		),
+		'protect-invalidaction' => array(
+			'code' => 'protect-invalidaction',
+			'info' => "Invalid protection type \"\$1\""
+		),
+		'protect-invalidlevel' => array(
+			'code' => 'protect-invalidlevel',
+			'info' => "Invalid protection level \"\$1\""
+		),
+		'toofewexpiries' => array(
+			'code' => 'toofewexpiries',
+			'info' => "\$1 expiry timestamps were provided where \$2 were needed"
+		),
+		'cantimport' => array(
+			'code' => 'cantimport',
+			'info' => "You don't have permission to import pages"
+		),
+		'cantimport-upload' => array(
+			'code' => 'cantimport-upload',
+			'info' => "You don't have permission to import uploaded pages"
+		),
 		'importnofile' => array( 'code' => 'nofile', 'info' => "You didn't upload a file" ),
-		'importuploaderrorsize' => array( 'code' => 'filetoobig', 'info' => 'The file you uploaded is bigger than the maximum upload size' ),
-		'importuploaderrorpartial' => array( 'code' => 'partialupload', 'info' => 'The file was only partially uploaded' ),
-		'importuploaderrortemp' => array( 'code' => 'notempdir', 'info' => 'The temporary upload directory is missing' ),
-		'importcantopen' => array( 'code' => 'cantopenfile', 'info' => "Couldn't open the uploaded file" ),
-		'import-noarticle' => array( 'code' => 'badinterwiki', 'info' => 'Invalid interwiki title specified' ),
-		'importbadinterwiki' => array( 'code' => 'badinterwiki', 'info' => 'Invalid interwiki title specified' ),
-		'import-unknownerror' => array( 'code' => 'import-unknownerror', 'info' => "Unknown error on import: \"\$1\"" ),
-		'cantoverwrite-sharedfile' => array( 'code' => 'cantoverwrite-sharedfile', 'info' => 'The target file exists on a shared repository and you do not have permission to override it' ),
-		'sharedfile-exists' => array( 'code' => 'fileexists-sharedrepo-perm', 'info' => 'The target file exists on a shared repository. Use the ignorewarnings parameter to override it.' ),
-		'mustbeposted' => array( 'code' => 'mustbeposted', 'info' => "The \$1 module requires a POST request" ),
-		'show' => array( 'code' => 'show', 'info' => 'Incorrect parameter - mutually exclusive values may not be supplied' ),
-		'specialpage-cantexecute' => array( 'code' => 'specialpage-cantexecute', 'info' => "You don't have permission to view the results of this special page" ),
-		'invalidoldimage' => array( 'code' => 'invalidoldimage', 'info' => 'The oldimage parameter has invalid format' ),
-		'nodeleteablefile' => array( 'code' => 'nodeleteablefile', 'info' => 'No such old version of the file' ),
-		'fileexists-forbidden' => array( 'code' => 'fileexists-forbidden', 'info' => 'A file with name "$1" already exists, and cannot be overwritten.' ),
-		'fileexists-shared-forbidden' => array( 'code' => 'fileexists-shared-forbidden', 'info' => 'A file with name "$1" already exists in the shared file repository, and cannot be overwritten.' ),
-		'filerevert-badversion' => array( 'code' => 'filerevert-badversion', 'info' => 'There is no previous local version of this file with the provided timestamp.' ),
+		'importuploaderrorsize' => array(
+			'code' => 'filetoobig',
+			'info' => 'The file you uploaded is bigger than the maximum upload size'
+		),
+		'importuploaderrorpartial' => array(
+			'code' => 'partialupload',
+			'info' => 'The file was only partially uploaded'
+		),
+		'importuploaderrortemp' => array(
+			'code' => 'notempdir',
+			'info' => 'The temporary upload directory is missing'
+		),
+		'importcantopen' => array(
+			'code' => 'cantopenfile',
+			'info' => "Couldn't open the uploaded file"
+		),
+		'import-noarticle' => array(
+			'code' => 'badinterwiki',
+			'info' => 'Invalid interwiki title specified'
+		),
+		'importbadinterwiki' => array(
+			'code' => 'badinterwiki',
+			'info' => 'Invalid interwiki title specified'
+		),
+		'import-unknownerror' => array(
+			'code' => 'import-unknownerror',
+			'info' => "Unknown error on import: \"\$1\""
+		),
+		'cantoverwrite-sharedfile' => array(
+			'code' => 'cantoverwrite-sharedfile',
+			'info' => 'The target file exists on a shared repository and you do not have permission to override it'
+		),
+		'sharedfile-exists' => array(
+			'code' => 'fileexists-sharedrepo-perm',
+			'info' => 'The target file exists on a shared repository. Use the ignorewarnings parameter to override it.'
+		),
+		'mustbeposted' => array(
+			'code' => 'mustbeposted',
+			'info' => "The \$1 module requires a POST request"
+		),
+		'show' => array(
+			'code' => 'show',
+			'info' => 'Incorrect parameter - mutually exclusive values may not be supplied'
+		),
+		'specialpage-cantexecute' => array(
+			'code' => 'specialpage-cantexecute',
+			'info' => "You don't have permission to view the results of this special page"
+		),
+		'invalidoldimage' => array(
+			'code' => 'invalidoldimage',
+			'info' => 'The oldimage parameter has invalid format'
+		),
+		'nodeleteablefile' => array(
+			'code' => 'nodeleteablefile',
+			'info' => 'No such old version of the file'
+		),
+		'fileexists-forbidden' => array(
+			'code' => 'fileexists-forbidden',
+			'info' => 'A file with name "$1" already exists, and cannot be overwritten.'
+		),
+		'fileexists-shared-forbidden' => array(
+			'code' => 'fileexists-shared-forbidden',
+			'info' => 'A file with name "$1" already exists in the shared file repository, and cannot be overwritten.'
+		),
+		'filerevert-badversion' => array(
+			'code' => 'filerevert-badversion',
+			'info' => 'There is no previous local version of this file with the provided timestamp.'
+		),
 
 		// ApiEditPage messages
-		'noimageredirect-anon' => array( 'code' => 'noimageredirect-anon', 'info' => "Anonymous users can't create image redirects" ),
-		'noimageredirect-logged' => array( 'code' => 'noimageredirect', 'info' => "You don't have permission to create image redirects" ),
-		'spamdetected' => array( 'code' => 'spamdetected', 'info' => "Your edit was refused because it contained a spam fragment: \"\$1\"" ),
-		'contenttoobig' => array( 'code' => 'contenttoobig', 'info' => "The content you supplied exceeds the article size limit of \$1 kilobytes" ),
+		'noimageredirect-anon' => array(
+			'code' => 'noimageredirect-anon',
+			'info' => "Anonymous users can't create image redirects"
+		),
+		'noimageredirect-logged' => array(
+			'code' => 'noimageredirect',
+			'info' => "You don't have permission to create image redirects"
+		),
+		'spamdetected' => array(
+			'code' => 'spamdetected',
+			'info' => "Your edit was refused because it contained a spam fragment: \"\$1\""
+		),
+		'contenttoobig' => array(
+			'code' => 'contenttoobig',
+			'info' => "The content you supplied exceeds the article size limit of \$1 kilobytes"
+		),
 		'noedit-anon' => array( 'code' => 'noedit-anon', 'info' => "Anonymous users can't edit pages" ),
 		'noedit' => array( 'code' => 'noedit', 'info' => "You don't have permission to edit pages" ),
-		'wasdeleted' => array( 'code' => 'pagedeleted', 'info' => "The page has been deleted since you fetched its timestamp" ),
-		'blankpage' => array( 'code' => 'emptypage', 'info' => "Creating new, empty pages is not allowed" ),
+		'wasdeleted' => array(
+			'code' => 'pagedeleted',
+			'info' => "The page has been deleted since you fetched its timestamp"
+		),
+		'blankpage' => array(
+			'code' => 'emptypage',
+			'info' => "Creating new, empty pages is not allowed"
+		),
 		'editconflict' => array( 'code' => 'editconflict', 'info' => "Edit conflict detected" ),
 		'hashcheckfailed' => array( 'code' => 'badmd5', 'info' => "The supplied MD5 hash was incorrect" ),
-		'missingtext' => array( 'code' => 'notext', 'info' => "One of the text, appendtext, prependtext and undo parameters must be set" ),
-		'emptynewsection' => array( 'code' => 'emptynewsection', 'info' => 'Creating empty new sections is not possible.' ),
-		'revwrongpage' => array( 'code' => 'revwrongpage', 'info' => "r\$1 is not a revision of \"\$2\"" ),
-		'undo-failure' => array( 'code' => 'undofailure', 'info' => 'Undo failed due to conflicting intermediate edits' ),
+		'missingtext' => array(
+			'code' => 'notext',
+			'info' => "One of the text, appendtext, prependtext and undo parameters must be set"
+		),
+		'emptynewsection' => array(
+			'code' => 'emptynewsection',
+			'info' => 'Creating empty new sections is not possible.'
+		),
+		'revwrongpage' => array(
+			'code' => 'revwrongpage',
+			'info' => "r\$1 is not a revision of \"\$2\""
+		),
+		'undo-failure' => array(
+			'code' => 'undofailure',
+			'info' => 'Undo failed due to conflicting intermediate edits'
+		),
+		'content-not-allowed-here' => array(
+			'code' => 'contentnotallowedhere',
+			'info' => 'Content model "$1" is not allowed at title "$2"'
+		),
 
 		// Messages from WikiPage::doEit()
-		'edit-hook-aborted' => array( 'code' => 'edit-hook-aborted', 'info' => "Your edit was aborted by an ArticleSave hook" ),
-		'edit-gone-missing' => array( 'code' => 'edit-gone-missing', 'info' => "The page you tried to edit doesn't seem to exist anymore" ),
+		'edit-hook-aborted' => array(
+			'code' => 'edit-hook-aborted',
+			'info' => "Your edit was aborted by an ArticleSave hook"
+		),
+		'edit-gone-missing' => array(
+			'code' => 'edit-gone-missing',
+			'info' => "The page you tried to edit doesn't seem to exist anymore"
+		),
 		'edit-conflict' => array( 'code' => 'editconflict', 'info' => "Edit conflict detected" ),
-		'edit-already-exists' => array( 'code' => 'edit-already-exists', 'info' => "It seems the page you tried to create already exist" ),
+		'edit-already-exists' => array(
+			'code' => 'edit-already-exists',
+			'info' => 'It seems the page you tried to create already exist'
+		),
 
 		// uploadMsgs
 		'invalid-file-key' => array( 'code' => 'invalid-file-key', 'info' => 'Not a valid file key' ),
 		'nouploadmodule' => array( 'code' => 'nouploadmodule', 'info' => 'No upload module set' ),
-		'uploaddisabled' => array( 'code' => 'uploaddisabled', 'info' => 'Uploads are not enabled. Make sure $wgEnableUploads is set to true in LocalSettings.php and the PHP ini setting file_uploads is true' ),
-		'copyuploaddisabled' => array( 'code' => 'copyuploaddisabled', 'info' => 'Uploads by URL is not enabled. Make sure $wgAllowCopyUploads is set to true in LocalSettings.php.' ),
-		'copyuploadbaddomain' => array( 'code' => 'copyuploadbaddomain', 'info' => 'Uploads by URL are not allowed from this domain.' ),
-		'copyuploadbadurl' => array( 'code' => 'copyuploadbadurl', 'info' => 'Upload not allowed from this URL.' ),
-
-		'filename-tooshort' => array( 'code' => 'filename-tooshort', 'info' => 'The filename is too short' ),
+		'uploaddisabled' => array(
+			'code' => 'uploaddisabled',
+			'info' => 'Uploads are not enabled. Make sure $wgEnableUploads is set to true in LocalSettings.php and the PHP ini setting file_uploads is true'
+		),
+		'copyuploaddisabled' => array(
+			'code' => 'copyuploaddisabled',
+			'info' => 'Uploads by URL is not enabled. Make sure $wgAllowCopyUploads is set to true in LocalSettings.php.'
+		),
+		'copyuploadbaddomain' => array(
+			'code' => 'copyuploadbaddomain',
+			'info' => 'Uploads by URL are not allowed from this domain.'
+		),
+		'copyuploadbadurl' => array(
+			'code' => 'copyuploadbadurl',
+			'info' => 'Upload not allowed from this URL.'
+		),
+
+		'filename-tooshort' => array(
+			'code' => 'filename-tooshort',
+			'info' => 'The filename is too short'
+		),
 		'filename-toolong' => array( 'code' => 'filename-toolong', 'info' => 'The filename is too long' ),
-		'illegal-filename' => array( 'code' => 'illegal-filename', 'info' => 'The filename is not allowed' ),
-		'filetype-missing' => array( 'code' => 'filetype-missing', 'info' => 'The file is missing an extension' ),
+		'illegal-filename' => array(
+			'code' => 'illegal-filename',
+			'info' => 'The filename is not allowed'
+		),
+		'filetype-missing' => array(
+			'code' => 'filetype-missing',
+			'info' => 'The file is missing an extension'
+		),
 
 		'mustbeloggedin' => array( 'code' => 'mustbeloggedin', 'info' => 'You must be logged in to $1.' )
 	);
+	// @codingStandardsIgnoreEnd
 
 	/**
 	 * Helper function for readonly errors
@@ -1426,7 +1734,7 @@ abstract class ApiBase extends ContextSource {
 
 	/**
 	 * Output the error message related to a certain array
-	 * @param $error (array|string) Element of a getUserPermissionsErrors()-style array
+	 * @param array|string $error Element of a getUserPermissionsErrors()-style array
 	 */
 	public function dieUsageMsg( $error ) {
 		# most of the time we send a 1 element, so we might as well send it as
@@ -1441,26 +1749,25 @@ abstract class ApiBase extends ContextSource {
 	/**
 	 * Will only set a warning instead of failing if the global $wgDebugAPI
 	 * is set to true. Otherwise behaves exactly as dieUsageMsg().
-	 * @param $error (array|string) Element of a getUserPermissionsErrors()-style array
+	 * @param array|string $error Element of a getUserPermissionsErrors()-style array
 	 * @since 1.21
 	 */
 	public function dieUsageMsgOrDebug( $error ) {
-		global $wgDebugAPI;
-		if ( $wgDebugAPI !== true ) {
+		if ( $this->getConfig()->get( 'DebugAPI' ) !== true ) {
 			$this->dieUsageMsg( $error );
-		} else {
-			if ( is_string( $error ) ) {
-				$error = array( $error );
-			}
-			$parsed = $this->parseMsg( $error );
-			$this->setWarning( '$wgDebugAPI: ' . $parsed['code']
-				. ' - ' . $parsed['info'] );
 		}
+
+		if ( is_string( $error ) ) {
+			$error = array( $error );
+		}
+		$parsed = $this->parseMsg( $error );
+		$this->setWarning( '$wgDebugAPI: ' . $parsed['code'] . ' - ' . $parsed['info'] );
 	}
 
 	/**
-	 * Die with the $prefix.'badcontinue' error. This call is common enough to make it into the base method.
-	 * @param $condition boolean will only die if this value is true
+	 * Die with the $prefix.'badcontinue' error. This call is common enough to
+	 * make it into the base method.
+	 * @param bool $condition Will only die if this value is true
 	 * @since 1.21
 	 */
 	protected function dieContinueUsageIf( $condition ) {
@@ -1502,193 +1809,311 @@ abstract class ApiBase extends ContextSource {
 	 * Internal code errors should be reported with this method
 	 * @param string $method Method or function name
 	 * @param string $message Error message
+	 * @throws MWException
 	 */
 	protected static function dieDebug( $method, $message ) {
 		throw new MWException( "Internal error in $method: $message" );
 	}
 
-	/**
-	 * Indicates if this module needs maxlag to be checked
-	 * @return bool
-	 */
-	public function shouldCheckMaxlag() {
-		return true;
-	}
+	/**@}*/
 
-	/**
-	 * Indicates whether this module requires read rights
-	 * @return bool
+	/************************************************************************//**
+	 * @name   Help message generation
+	 * @{
 	 */
-	public function isReadMode() {
-		return true;
-	}
-	/**
-	 * Indicates whether this module requires write mode
-	 * @return bool
-	 */
-	public function isWriteMode() {
-		return false;
-	}
 
 	/**
-	 * Indicates whether this module must be called with a POST request
-	 * @return bool
+	 * Generates help message for this module, or false if there is no description
+	 * @return string|bool
 	 */
-	public function mustBePosted() {
-		return false;
-	}
+	public function makeHelpMsg() {
+		static $lnPrfx = "\n  ";
 
-	/**
-	 * Returns whether this module requires a token to execute
-	 * It is used to show possible errors in action=paraminfo
-	 * see bug 25248
-	 * @return bool
-	 */
-	public function needsToken() {
-		return false;
-	}
+		$msg = $this->getFinalDescription();
 
-	/**
-	 * Returns the token salt if there is one,
-	 * '' if the module doesn't require a salt,
-	 * else false if the module doesn't need a token
-	 * You have also to override needsToken()
-	 * Value is passed to User::getEditToken
-	 * @return bool|string|array
-	 */
-	public function getTokenSalt() {
-		return false;
-	}
+		if ( $msg !== false ) {
 
-	/**
-	 * Gets the user for whom to get the watchlist
-	 *
-	 * @param $params array
-	 * @return User
-	 */
-	public function getWatchlistUser( $params ) {
-		if ( !is_null( $params['owner'] ) && !is_null( $params['token'] ) ) {
-			$user = User::newFromName( $params['owner'], false );
-			if ( !( $user && $user->getId() ) ) {
-				$this->dieUsage( 'Specified user does not exist', 'bad_wlowner' );
+			if ( !is_array( $msg ) ) {
+				$msg = array(
+					$msg
+				);
 			}
-			$token = $user->getOption( 'watchlisttoken' );
-			if ( $token == '' || $token != $params['token'] ) {
-				$this->dieUsage( 'Incorrect watchlist token provided -- please set a correct token in Special:Preferences', 'bad_wltoken' );
+			$msg = $lnPrfx . implode( $lnPrfx, $msg ) . "\n";
+
+			$msg .= $this->makeHelpArrayToString( $lnPrfx, false, $this->getHelpUrls() );
+
+			if ( $this->isReadMode() ) {
+				$msg .= "\nThis module requires read rights";
 			}
-		} else {
-			if ( !$this->getUser()->isLoggedIn() ) {
-				$this->dieUsage( 'You must be logged-in to have a watchlist', 'notloggedin' );
+			if ( $this->isWriteMode() ) {
+				$msg .= "\nThis module requires write rights";
 			}
-			if ( !$this->getUser()->isAllowed( 'viewmywatchlist' ) ) {
-				$this->dieUsage( 'You don\'t have permission to view your watchlist', 'permissiondenied' );
+			if ( $this->mustBePosted() ) {
+				$msg .= "\nThis module only accepts POST requests";
+			}
+			if ( $this->isReadMode() || $this->isWriteMode() ||
+				$this->mustBePosted()
+			) {
+				$msg .= "\n";
+			}
+
+			// Parameters
+			$paramsMsg = $this->makeHelpMsgParameters();
+			if ( $paramsMsg !== false ) {
+				$msg .= "Parameters:\n$paramsMsg";
+			}
+
+			$examples = $this->getExamples();
+			if ( $examples ) {
+				if ( !is_array( $examples ) ) {
+					$examples = array(
+						$examples
+					);
+				}
+				$msg .= "Example" . ( count( $examples ) > 1 ? 's' : '' ) . ":\n";
+				foreach ( $examples as $k => $v ) {
+					if ( is_numeric( $k ) ) {
+						$msg .= "  $v\n";
+					} else {
+						if ( is_array( $v ) ) {
+							$msgExample = implode( "\n", array_map( array( $this, 'indentExampleText' ), $v ) );
+						} else {
+							$msgExample = "  $v";
+						}
+						$msgExample .= ":";
+						$msg .= wordwrap( $msgExample, 100, "\n" ) . "\n    $k\n";
+					}
+				}
 			}
-			$user = $this->getUser();
 		}
-		return $user;
+
+		return $msg;
 	}
 
 	/**
-	 * @return bool|string|array Returns a false if the module has no help url, else returns a (array of) string
+	 * @param string $item
+	 * @return string
 	 */
-	public function getHelpUrls() {
-		return false;
+	private function indentExampleText( $item ) {
+		return "  " . $item;
 	}
 
 	/**
-	 * Returns a list of all possible errors returned by the module
-	 *
-	 * Don't call this function directly: use getFinalPossibleErrors() to allow
-	 * hooks to modify parameters as needed.
-	 *
-	 * @return array in the format of array( key, param1, param2, ... ) or array( 'code' => ..., 'info' => ... )
+	 * @param string $prefix Text to split output items
+	 * @param string $title What is being output
+	 * @param string|array $input
+	 * @return string
 	 */
-	public function getPossibleErrors() {
-		$ret = array();
-
-		$params = $this->getFinalParams();
-		if ( $params ) {
-			foreach ( $params as $paramName => $paramSettings ) {
-				if ( isset( $paramSettings[ApiBase::PARAM_REQUIRED] ) && $paramSettings[ApiBase::PARAM_REQUIRED] ) {
-					$ret[] = array( 'missingparam', $paramName );
-				}
-			}
-			if ( array_key_exists( 'continue', $params ) ) {
-				$ret[] = array(
-					'code' => 'badcontinue',
-					'info' => 'Invalid continue param. You should pass the original value returned by the previous query'
-				);
-			}
-		}
-
-		if ( $this->mustBePosted() ) {
-			$ret[] = array( 'mustbeposted', $this->getModuleName() );
-		}
-
-		if ( $this->isReadMode() ) {
-			$ret[] = array( 'readrequired' );
+	protected function makeHelpArrayToString( $prefix, $title, $input ) {
+		if ( $input === false ) {
+			return '';
 		}
-
-		if ( $this->isWriteMode() ) {
-			$ret[] = array( 'writerequired' );
-			$ret[] = array( 'writedisabled' );
+		if ( !is_array( $input ) ) {
+			$input = array( $input );
 		}
 
-		if ( $this->needsToken() ) {
-			if ( !isset( $params['token'][ApiBase::PARAM_REQUIRED] )
-				|| !$params['token'][ApiBase::PARAM_REQUIRED]
-			) {
-				// Add token as possible missing parameter, if not already done
-				$ret[] = array( 'missingparam', 'token' );
+		if ( count( $input ) > 0 ) {
+			if ( $title ) {
+				$msg = $title . ( count( $input ) > 1 ? 's' : '' ) . ":\n  ";
+			} else {
+				$msg = '  ';
 			}
-			$ret[] = array( 'sessionfailure' );
+			$msg .= implode( $prefix, $input ) . "\n";
+
+			return $msg;
 		}
 
-		return $ret;
+		return '';
 	}
 
 	/**
-	 * Get final list of possible errors, after hooks have had a chance to
-	 * tweak it as needed.
-	 *
-	 * @return array
-	 * @since 1.22
+	 * Generates the parameter descriptions for this module, to be displayed in the
+	 * module's help.
+	 * @return string|bool
 	 */
-	public function getFinalPossibleErrors() {
-		$possibleErrors = $this->getPossibleErrors();
-		wfRunHooks( 'APIGetPossibleErrors', array( $this, &$possibleErrors ) );
-		return $possibleErrors;
-	}
+	public function makeHelpMsgParameters() {
+		$params = $this->getFinalParams( ApiBase::GET_VALUES_FOR_HELP );
+		if ( $params ) {
 
-	/**
-	 * Parses a list of errors into a standardised format
-	 * @param array $errors List of errors. Items can be in the for array( key, param1, param2, ... ) or array( 'code' => ..., 'info' => ... )
-	 * @return array Parsed list of errors with items in the form array( 'code' => ..., 'info' => ... )
-	 */
-	public function parseErrors( $errors ) {
-		$ret = array();
+			$paramsDescription = $this->getFinalParamDescription();
+			$msg = '';
+			$paramPrefix = "\n" . str_repeat( ' ', 24 );
+			$descWordwrap = "\n" . str_repeat( ' ', 28 );
+			foreach ( $params as $paramName => $paramSettings ) {
+				$desc = isset( $paramsDescription[$paramName] ) ? $paramsDescription[$paramName] : '';
+				if ( is_array( $desc ) ) {
+					$desc = implode( $paramPrefix, $desc );
+				}
 
-		foreach ( $errors as $row ) {
-			if ( isset( $row['code'] ) && isset( $row['info'] ) ) {
-				$ret[] = $row;
-			} else {
-				$ret[] = $this->parseMsg( $row );
+				//handle shorthand
+				if ( !is_array( $paramSettings ) ) {
+					$paramSettings = array(
+						self::PARAM_DFLT => $paramSettings,
+					);
+				}
+
+				//handle missing type
+				if ( !isset( $paramSettings[ApiBase::PARAM_TYPE] ) ) {
+					$dflt = isset( $paramSettings[ApiBase::PARAM_DFLT] )
+						? $paramSettings[ApiBase::PARAM_DFLT]
+						: null;
+					if ( is_bool( $dflt ) ) {
+						$paramSettings[ApiBase::PARAM_TYPE] = 'boolean';
+					} elseif ( is_string( $dflt ) || is_null( $dflt ) ) {
+						$paramSettings[ApiBase::PARAM_TYPE] = 'string';
+					} elseif ( is_int( $dflt ) ) {
+						$paramSettings[ApiBase::PARAM_TYPE] = 'integer';
+					}
+				}
+
+				if ( isset( $paramSettings[self::PARAM_DEPRECATED] )
+					&& $paramSettings[self::PARAM_DEPRECATED]
+				) {
+					$desc = "DEPRECATED! $desc";
+				}
+
+				if ( isset( $paramSettings[self::PARAM_REQUIRED] )
+					&& $paramSettings[self::PARAM_REQUIRED]
+				) {
+					$desc .= $paramPrefix . "This parameter is required";
+				}
+
+				$type = isset( $paramSettings[self::PARAM_TYPE] )
+					? $paramSettings[self::PARAM_TYPE]
+					: null;
+				if ( isset( $type ) ) {
+					$hintPipeSeparated = true;
+					$multi = isset( $paramSettings[self::PARAM_ISMULTI] )
+						? $paramSettings[self::PARAM_ISMULTI]
+						: false;
+					if ( $multi ) {
+						$prompt = 'Values (separate with \'|\'): ';
+					} else {
+						$prompt = 'One value: ';
+					}
+
+					if ( $type === 'submodule' ) {
+						$type = $this->getModuleManager()->getNames( $paramName );
+						sort( $type );
+					}
+					if ( is_array( $type ) ) {
+						$choices = array();
+						$nothingPrompt = '';
+						foreach ( $type as $t ) {
+							if ( $t === '' ) {
+								$nothingPrompt = 'Can be empty, or ';
+							} else {
+								$choices[] = $t;
+							}
+						}
+						$desc .= $paramPrefix . $nothingPrompt . $prompt;
+						$choicesstring = implode( ', ', $choices );
+						$desc .= wordwrap( $choicesstring, 100, $descWordwrap );
+						$hintPipeSeparated = false;
+					} else {
+						switch ( $type ) {
+							case 'namespace':
+								// Special handling because namespaces are
+								// type-limited, yet they are not given
+								$desc .= $paramPrefix . $prompt;
+								$desc .= wordwrap( implode( ', ', MWNamespace::getValidNamespaces() ),
+									100, $descWordwrap );
+								$hintPipeSeparated = false;
+								break;
+							case 'limit':
+								$desc .= $paramPrefix . "No more than {$paramSettings[self::PARAM_MAX]}";
+								if ( isset( $paramSettings[self::PARAM_MAX2] ) ) {
+									$desc .= " ({$paramSettings[self::PARAM_MAX2]} for bots)";
+								}
+								$desc .= ' allowed';
+								break;
+							case 'integer':
+								$s = $multi ? 's' : '';
+								$hasMin = isset( $paramSettings[self::PARAM_MIN] );
+								$hasMax = isset( $paramSettings[self::PARAM_MAX] );
+								if ( $hasMin || $hasMax ) {
+									if ( !$hasMax ) {
+										$intRangeStr = "The value$s must be no less than " .
+											"{$paramSettings[self::PARAM_MIN]}";
+									} elseif ( !$hasMin ) {
+										$intRangeStr = "The value$s must be no more than " .
+											"{$paramSettings[self::PARAM_MAX]}";
+									} else {
+										$intRangeStr = "The value$s must be between " .
+											"{$paramSettings[self::PARAM_MIN]} and {$paramSettings[self::PARAM_MAX]}";
+									}
+
+									$desc .= $paramPrefix . $intRangeStr;
+								}
+								break;
+							case 'upload':
+								$desc .= $paramPrefix . "Must be posted as a file upload using multipart/form-data";
+								break;
+						}
+					}
+
+					if ( $multi ) {
+						if ( $hintPipeSeparated ) {
+							$desc .= $paramPrefix . "Separate values with '|'";
+						}
+
+						$isArray = is_array( $type );
+						if ( !$isArray
+							|| $isArray && count( $type ) > self::LIMIT_SML1
+						) {
+							$desc .= $paramPrefix . "Maximum number of values " .
+								self::LIMIT_SML1 . " (" . self::LIMIT_SML2 . " for bots)";
+						}
+					}
+				}
+
+				$default = isset( $paramSettings[self::PARAM_DFLT] ) ? $paramSettings[self::PARAM_DFLT] : null;
+				if ( !is_null( $default ) && $default !== false ) {
+					$desc .= $paramPrefix . "Default: $default";
+				}
+
+				$msg .= sprintf( "  %-19s - %s\n", $this->encodeParamName( $paramName ), $desc );
 			}
+
+			return $msg;
 		}
-		return $ret;
+
+		return false;
 	}
 
+	/**@}*/
+
+	/************************************************************************//**
+	 * @name   Profiling
+	 * @{
+	 */
+
 	/**
 	 * Profiling: total module execution time
 	 */
 	private $mTimeIn = 0, $mModuleTime = 0;
 
 	/**
+	 * Get the name of the module as shown in the profiler log
+	 *
+	 * @param DatabaseBase|bool $db
+	 *
+	 * @return string
+	 */
+	public function getModuleProfileName( $db = false ) {
+		if ( $db ) {
+			return 'API:' . $this->mModuleName . '-DB';
+		}
+
+		return 'API:' . $this->mModuleName;
+	}
+
+	/**
 	 * Start module profiling
 	 */
 	public function profileIn() {
 		if ( $this->mTimeIn !== 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'called twice without calling profileOut()' );
+			ApiBase::dieDebug( __METHOD__, 'Called twice without calling profileOut()' );
 		}
 		$this->mTimeIn = microtime( true );
 		wfProfileIn( $this->getModuleProfileName() );
@@ -1699,10 +2124,13 @@ abstract class ApiBase extends ContextSource {
 	 */
 	public function profileOut() {
 		if ( $this->mTimeIn === 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'called without calling profileIn() first' );
+			ApiBase::dieDebug( __METHOD__, 'Called without calling profileIn() first' );
 		}
 		if ( $this->mDBTimeIn !== 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'must be called after database profiling is done with profileDBOut()' );
+			ApiBase::dieDebug(
+				__METHOD__,
+				'Must be called after database profiling is done with profileDBOut()'
+			);
 		}
 
 		$this->mModuleTime += microtime( true ) - $this->mTimeIn;
@@ -1729,8 +2157,9 @@ abstract class ApiBase extends ContextSource {
 	 */
 	public function getProfileTime() {
 		if ( $this->mTimeIn !== 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'called without calling profileOut() first' );
+			ApiBase::dieDebug( __METHOD__, 'Called without calling profileOut() first' );
 		}
+
 		return $this->mModuleTime;
 	}
 
@@ -1744,10 +2173,13 @@ abstract class ApiBase extends ContextSource {
 	 */
 	public function profileDBIn() {
 		if ( $this->mTimeIn === 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'must be called while profiling the entire module with profileIn()' );
+			ApiBase::dieDebug(
+				__METHOD__,
+				'Must be called while profiling the entire module with profileIn()'
+			);
 		}
 		if ( $this->mDBTimeIn !== 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'called twice without calling profileDBOut()' );
+			ApiBase::dieDebug( __METHOD__, 'Called twice without calling profileDBOut()' );
 		}
 		$this->mDBTimeIn = microtime( true );
 		wfProfileIn( $this->getModuleProfileName( true ) );
@@ -1758,10 +2190,11 @@ abstract class ApiBase extends ContextSource {
 	 */
 	public function profileDBOut() {
 		if ( $this->mTimeIn === 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'must be called while profiling the entire module with profileIn()' );
+			ApiBase::dieDebug( __METHOD__, 'Must be called while profiling ' .
+				'the entire module with profileIn()' );
 		}
 		if ( $this->mDBTimeIn === 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'called without calling profileDBIn() first' );
+			ApiBase::dieDebug( __METHOD__, 'Called without calling profileDBIn() first' );
 		}
 
 		$time = microtime( true ) - $this->mDBTimeIn;
@@ -1778,36 +2211,168 @@ abstract class ApiBase extends ContextSource {
 	 */
 	public function getProfileDBTime() {
 		if ( $this->mDBTimeIn !== 0 ) {
-			ApiBase::dieDebug( __METHOD__, 'called without calling profileDBOut() first' );
+			ApiBase::dieDebug( __METHOD__, 'Called without calling profileDBOut() first' );
 		}
+
 		return $this->mDBTime;
 	}
 
 	/**
-	 * Gets a default slave database connection object
-	 * @return DatabaseBase
+	 * Write logging information for API features to a debug log, for usage
+	 * analysis.
+	 * @param string $feature Feature being used.
 	 */
-	protected function getDB() {
-		if ( !isset( $this->mSlaveDB ) ) {
-			$this->profileDBIn();
-			$this->mSlaveDB = wfGetDB( DB_SLAVE, 'api' );
-			$this->profileDBOut();
-		}
-		return $this->mSlaveDB;
+	protected function logFeatureUsage( $feature ) {
+		$request = $this->getRequest();
+		$s = '"' . addslashes( $feature ) . '"' .
+			' "' . wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) . '"' .
+			' "' . $request->getIP() . '"' .
+			' "' . addslashes( $request->getHeader( 'Referer' ) ) . '"' .
+			' "' . addslashes( $request->getHeader( 'User-agent' ) ) . '"';
+		wfDebugLog( 'api-feature-usage', $s, 'private' );
 	}
 
+	/**@}*/
+
+	/************************************************************************//**
+	 * @name   Deprecated
+	 * @{
+	 */
+
+	/// @deprecated since 1.24
+	const PROP_ROOT = 'ROOT';
+	/// @deprecated since 1.24
+	const PROP_LIST = 'LIST';
+	/// @deprecated since 1.24
+	const PROP_TYPE = 0;
+	/// @deprecated since 1.24
+	const PROP_NULLABLE = 1;
+
 	/**
-	 * Debugging function that prints a value and an optional backtrace
-	 * @param $value mixed Value to print
-	 * @param string $name Description of the printed value
-	 * @param bool $backtrace If true, print a backtrace
+	 * Formerly returned a string that identifies the version of the extending
+	 * class. Typically included the class name, the svn revision, timestamp,
+	 * and last author. Usually done with SVN's Id keyword
+	 *
+	 * @deprecated since 1.21, version string is no longer supported
+	 * @return string
 	 */
-	public static function debugPrint( $value, $name = 'unknown', $backtrace = false ) {
-		print "\n\n<pre><b>Debugging value '$name':</b>\n\n";
-		var_export( $value );
-		if ( $backtrace ) {
-			print "\n" . wfBacktrace();
-		}
-		print "\n</pre>\n";
+	public function getVersion() {
+		wfDeprecated( __METHOD__, '1.21' );
+		return '';
+	}
+
+	/**
+	 * Formerly used to fetch a list of possible properites in the result,
+	 * somehow organized with respect to the prop parameter that causes them to
+	 * be returned. The specific semantics of the return value was never
+	 * specified. Since this was never possible to be accurately updated, it
+	 * has been removed.
+	 *
+	 * @deprecated since 1.24
+	 * @return array|bool
+	 */
+	protected function getResultProperties() {
+		wfDeprecated( __METHOD__, '1.24' );
+		return false;
+	}
+
+	/**
+	 * @see self::getResultProperties()
+	 * @deprecated since 1.24
+	 * @return array|bool
+	 */
+	public function getFinalResultProperties() {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
+	}
+
+	/**
+	 * @see self::getResultProperties()
+	 * @deprecated since 1.24
+	 */
+	protected static function addTokenProperties( &$props, $tokenFunctions ) {
+		wfDeprecated( __METHOD__, '1.24' );
+	}
+
+	/**
+	 * @see self::getPossibleErrors()
+	 * @deprecated since 1.24
+	 * @return array
+	 */
+	public function getRequireOnlyOneParameterErrorMessages( $params ) {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
+	}
+
+	/**
+	 * @see self::getPossibleErrors()
+	 * @deprecated since 1.24
+	 * @return array
+	 */
+	public function getRequireMaxOneParameterErrorMessages( $params ) {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
+	}
+
+	/**
+	 * @see self::getPossibleErrors()
+	 * @deprecated since 1.24
+	 * @return array
+	 */
+	public function getRequireAtLeastOneParameterErrorMessages( $params ) {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
+	}
+
+	/**
+	 * @see self::getPossibleErrors()
+	 * @deprecated since 1.24
+	 * @return array
+	 */
+	public function getTitleOrPageIdErrorMessage() {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
+	}
+
+	/**
+	 * This formerly attempted to return a list of all possible errors returned
+	 * by the module. However, this was impossible to maintain in many cases
+	 * since errors could come from other areas of MediaWiki and in some cases
+	 * from arbitrary extension hooks. Since a partial list claiming to be
+	 * comprehensive is unlikely to be useful, it was removed.
+	 *
+	 * @deprecated since 1.24
+	 * @return array
+	 */
+	public function getPossibleErrors() {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
 	}
+
+	/**
+	 * @see self::getPossibleErrors()
+	 * @deprecated since 1.24
+	 * @return array
+	 */
+	public function getFinalPossibleErrors() {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
+	}
+
+	/**
+	 * @see self::getPossibleErrors()
+	 * @deprecated since 1.24
+	 * @return array
+	 */
+	public function parseErrors( $errors ) {
+		wfDeprecated( __METHOD__, '1.24' );
+		return array();
+	}
+
+	/**@}*/
 }
+
+/**
+ * For really cool vim folding this needs to be at the end:
+ * vim: foldmarker=@{,@} foldmethod=marker
+ */