ApiUpload.php

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<?php
class ApiUpload extends ApiBase {

    protected $mUpload = null;

    protected $mParams;

    public function execute() {
        global $wgEnableAsyncUploads;

        // Check whether upload is enabled
        if ( !UploadBase::isEnabled() ) {
            $this->dieUsageMsg( 'uploaddisabled' );
        }

        $user = $this->getUser();

        // Parameter handling
        $this->mParams = $this->extractRequestParams();
        $request = $this->getMain()->getRequest();
        // Check if async mode is actually supported (jobs done in cli mode)
        $this->mParams['async'] = ( $this->mParams['async'] && $wgEnableAsyncUploads );
        // Add the uploaded file to the params array
        $this->mParams['file'] = $request->getFileName( 'file' );
        $this->mParams['chunk'] = $request->getFileName( 'chunk' );

        // Copy the session key to the file key, for backward compatibility.
        if ( !$this->mParams['filekey'] && $this->mParams['sessionkey'] ) {
            $this->mParams['filekey'] = $this->mParams['sessionkey'];
        }

        // Select an upload module
        try {
            if ( !$this->selectUploadModule() ) {
                return; // not a true upload, but a status request or similar
            } elseif ( !isset( $this->mUpload ) ) {
                $this->dieUsage( 'No upload module set', 'nomodule' );
            }
        } catch ( UploadStashException $e ) { // XXX: don't spam exception log
            $this->dieUsage( get_class( $e ) . ": " . $e->getMessage(), 'stasherror' );
        }

        // First check permission to upload
        $this->checkPermissions( $user );

        // Fetch the file (usually a no-op)
        $status = $this->mUpload->fetchFile();
        if ( !$status->isGood() ) {
            $errors = $status->getErrorsArray();
            $error = array_shift( $errors[0] );
            $this->dieUsage( 'Error fetching file from remote source', $error, 0, $errors[0] );
        }

        // Check if the uploaded file is sane
        if ( $this->mParams['chunk'] ) {
            $maxSize = $this->mUpload->getMaxUploadSize();
            if ( $this->mParams['filesize'] > $maxSize ) {
                $this->dieUsage( 'The file you submitted was too large', 'file-too-large' );
            }
            if ( !$this->mUpload->getTitle() ) {
                $this->dieUsage( 'Invalid file title supplied', 'internal-error' );
            }
        } elseif ( $this->mParams['async'] && $this->mParams['filekey'] ) {
            // defer verification to background process
        } else {
            wfDebug( __METHOD__ . 'about to verify' );
            $this->verifyUpload();
        }

        // Check if the user has the rights to modify or overwrite the requested title
        // (This check is irrelevant if stashing is already requested, since the errors
        //  can always be fixed by changing the title)
        if ( !$this->mParams['stash'] ) {
            $permErrors = $this->mUpload->verifyTitlePermissions( $user );
            if ( $permErrors !== true ) {
                $this->dieRecoverableError( $permErrors[0], 'filename' );
            }
        }

        // Get the result based on the current upload context:
        try {
            $result = $this->getContextResult();
            if ( $result['result'] === 'Success' ) {
                $result['imageinfo'] = $this->mUpload->getImageInfo( $this->getResult() );
            }
        } catch ( UploadStashException $e ) { // XXX: don't spam exception log
            $this->dieUsage( get_class( $e ) . ": " . $e->getMessage(), 'stasherror' );
        }

        $this->getResult()->addValue( null, $this->getModuleName(), $result );

        // Cleanup any temporary mess
        $this->mUpload->cleanupTempFile();
    }

    private function getContextResult() {
        $warnings = $this->getApiWarnings();
        if ( $warnings && !$this->mParams['ignorewarnings'] ) {
            // Get warnings formatted in result array format
            return $this->getWarningsResult( $warnings );
        } elseif ( $this->mParams['chunk'] ) {
            // Add chunk, and get result
            return $this->getChunkResult( $warnings );
        } elseif ( $this->mParams['stash'] ) {
            // Stash the file and get stash result
            return $this->getStashResult( $warnings );
        }
        // This is the most common case -- a normal upload with no warnings
        // performUpload will return a formatted properly for the API with status
        return $this->performUpload( $warnings );
    }

    private function getStashResult( $warnings ) {
        $result = array();
        // Some uploads can request they be stashed, so as not to publish them immediately.
        // In this case, a failure to stash ought to be fatal
        try {
            $result['result'] = 'Success';
            $result['filekey'] = $this->performStash();
            $result['sessionkey'] = $result['filekey']; // backwards compatibility
            if ( $warnings && count( $warnings ) > 0 ) {
                $result['warnings'] = $warnings;
            }
        } catch ( MWException $e ) {
            $this->dieUsage( $e->getMessage(), 'stashfailed' );
        }
        return $result;
    }

    private function getWarningsResult( $warnings ) {
        $result = array();
        $result['result'] = 'Warning';
        $result['warnings'] = $warnings;
        // in case the warnings can be fixed with some further user action, let's stash this upload
        // and return a key they can use to restart it
        try {
            $result['filekey'] = $this->performStash();
            $result['sessionkey'] = $result['filekey']; // backwards compatibility
        } catch ( MWException $e ) {
            $result['warnings']['stashfailed'] = $e->getMessage();
        }
        return $result;
    }

    private function getChunkResult( $warnings ) {
        $result = array();

        $result['result'] = 'Continue';
        if ( $warnings && count( $warnings ) > 0 ) {
            $result['warnings'] = $warnings;
        }
        $request = $this->getMain()->getRequest();
        $chunkPath = $request->getFileTempname( 'chunk' );
        $chunkSize = $request->getUpload( 'chunk' )->getSize();
        if ( $this->mParams['offset'] == 0 ) {
            try {
                $filekey = $this->performStash();
            } catch ( MWException $e ) {
                // FIXME: Error handling here is wrong/different from rest of this
                $this->dieUsage( $e->getMessage(), 'stashfailed' );
            }
        } else {
            $filekey = $this->mParams['filekey'];
            $status = $this->mUpload->addChunk(
                $chunkPath, $chunkSize, $this->mParams['offset'] );
            if ( !$status->isGood() ) {
                $this->dieUsage( $status->getWikiText(), 'stashfailed' );
                return array();
            }
        }

        // Check we added the last chunk:
        if ( $this->mParams['offset'] + $chunkSize == $this->mParams['filesize'] ) {
            if ( $this->mParams['async'] ) {
                $progress = UploadBase::getSessionStatus( $filekey );
                if ( $progress && $progress['result'] === 'Poll' ) {
                    $this->dieUsage( "Chunk assembly already in progress.", 'stashfailed' );
                }
                UploadBase::setSessionStatus(
                    $filekey,
                    array( 'result' => 'Poll',
                        'stage' => 'queued', 'status' => Status::newGood() )
                );
                $ok = JobQueueGroup::singleton()->push( new AssembleUploadChunksJob(
                    Title::makeTitle( NS_FILE, $filekey ),
                    array(
                        'filename' => $this->mParams['filename'],
                        'filekey' => $filekey,
                        'session' => $this->getContext()->exportSession()
                    )
                ) );
                if ( $ok ) {
                    $result['result'] = 'Poll';
                } else {
                    UploadBase::setSessionStatus( $filekey, false );
                    $this->dieUsage(
                        "Failed to start AssembleUploadChunks.php", 'stashfailed' );
                }
            } else {
                $status = $this->mUpload->concatenateChunks();
                if ( !$status->isGood() ) {
                    $this->dieUsage( $status->getWikiText(), 'stashfailed' );
                    return array();
                }

                // The fully concatenated file has a new filekey. So remove
                // the old filekey and fetch the new one.
                $this->mUpload->stash->removeFile( $filekey );
                $filekey = $this->mUpload->getLocalFile()->getFileKey();

                $result['result'] = 'Success';
            }
        }
        $result['filekey'] = $filekey;
        $result['offset'] = $this->mParams['offset'] + $chunkSize;
        return $result;
    }

    private function performStash() {
        try {
            $stashFile = $this->mUpload->stashFile();

            if ( !$stashFile ) {
                throw new MWException( 'Invalid stashed file' );
            }
            $fileKey = $stashFile->getFileKey();
        } catch ( MWException $e ) {
            $message = 'Stashing temporary file failed: ' . get_class( $e ) . ' ' . $e->getMessage();
            wfDebug( __METHOD__ . ' ' . $message . "\n" );
            throw new MWException( $message );
        }
        return $fileKey;
    }

    private function dieRecoverableError( $error, $parameter, $data = array() ) {
        try {
            $data['filekey'] = $this->performStash();
            $data['sessionkey'] = $data['filekey'];
        } catch ( MWException $e ) {
            $data['stashfailed'] = $e->getMessage();
        }
        $data['invalidparameter'] = $parameter;

        $parsed = $this->parseMsg( $error );
        $this->dieUsage( $parsed['info'], $parsed['code'], 0, $data );
    }

    protected function selectUploadModule() {
        $request = $this->getMain()->getRequest();

        // chunk or one and only one of the following parameters is needed
        if ( !$this->mParams['chunk'] ) {
            $this->requireOnlyOneParameter( $this->mParams,
                'filekey', 'file', 'url', 'statuskey' );
        }

        // Status report for "upload to stash"/"upload from stash"
        if ( $this->mParams['filekey'] && $this->mParams['checkstatus'] ) {
            $progress = UploadBase::getSessionStatus( $this->mParams['filekey'] );
            if ( !$progress ) {
                $this->dieUsage( 'No result in status data', 'missingresult' );
            } elseif ( !$progress['status']->isGood() ) {
                $this->dieUsage( $progress['status']->getWikiText(), 'stashfailed' );
            }
            if ( isset( $progress['status']->value['verification'] ) ) {
                $this->checkVerification( $progress['status']->value['verification'] );
            }
            unset( $progress['status'] ); // remove Status object
            $this->getResult()->addValue( null, $this->getModuleName(), $progress );
            return false;
        }

        if ( $this->mParams['statuskey'] ) {
            $this->checkAsyncDownloadEnabled();

            // Status request for an async upload
            $sessionData = UploadFromUrlJob::getSessionData( $this->mParams['statuskey'] );
            if ( !isset( $sessionData['result'] ) ) {
                $this->dieUsage( 'No result in session data', 'missingresult' );
            }
            if ( $sessionData['result'] == 'Warning' ) {
                $sessionData['warnings'] = $this->transformWarnings( $sessionData['warnings'] );
                $sessionData['sessionkey'] = $this->mParams['statuskey'];
            }
            $this->getResult()->addValue( null, $this->getModuleName(), $sessionData );
            return false;
        }

        // The following modules all require the filename parameter to be set
        if ( is_null( $this->mParams['filename'] ) ) {
            $this->dieUsageMsg( array( 'missingparam', 'filename' ) );
        }

        if ( $this->mParams['chunk'] ) {
            // Chunk upload
            $this->mUpload = new UploadFromChunks();
            if ( isset( $this->mParams['filekey'] ) ) {
                // handle new chunk
                $this->mUpload->continueChunks(
                    $this->mParams['filename'],
                    $this->mParams['filekey'],
                    $request->getUpload( 'chunk' )
                );
            } else {
                // handle first chunk
                $this->mUpload->initialize(
                    $this->mParams['filename'],
                    $request->getUpload( 'chunk' )
                );
            }
        } elseif ( isset( $this->mParams['filekey'] ) ) {
            // Upload stashed in a previous request
            if ( !UploadFromStash::isValidKey( $this->mParams['filekey'] ) ) {
                $this->dieUsageMsg( 'invalid-file-key' );
            }

            $this->mUpload = new UploadFromStash( $this->getUser() );
            // This will not download the temp file in initialize() in async mode.
            // We still have enough information to call checkWarnings() and such.
            $this->mUpload->initialize(
                $this->mParams['filekey'], $this->mParams['filename'], !$this->mParams['async']
            );
        } elseif ( isset( $this->mParams['file'] ) ) {
            $this->mUpload = new UploadFromFile();
            $this->mUpload->initialize(
                $this->mParams['filename'],
                $request->getUpload( 'file' )
            );
        } elseif ( isset( $this->mParams['url'] ) ) {
            // Make sure upload by URL is enabled:
            if ( !UploadFromUrl::isEnabled() ) {
                $this->dieUsageMsg( 'copyuploaddisabled' );
            }

            if ( !UploadFromUrl::isAllowedHost( $this->mParams['url'] ) ) {
                $this->dieUsageMsg( 'copyuploadbaddomain' );
            }

            if ( !UploadFromUrl::isAllowedUrl( $this->mParams['url'] ) ) {
                $this->dieUsageMsg( 'copyuploadbadurl' );
            }

            $async = false;
            if ( $this->mParams['asyncdownload'] ) {
                $this->checkAsyncDownloadEnabled();

                if ( $this->mParams['leavemessage'] && !$this->mParams['ignorewarnings'] ) {
                    $this->dieUsage( 'Using leavemessage without ignorewarnings is not supported',
                        'missing-ignorewarnings' );
                }

                if ( $this->mParams['leavemessage'] ) {
                    $async = 'async-leavemessage';
                } else {
                    $async = 'async';
                }
            }
            $this->mUpload = new UploadFromUrl;
            $this->mUpload->initialize( $this->mParams['filename'],
                $this->mParams['url'], $async );
        }

        return true;
    }

    protected function checkPermissions( $user ) {
        // Check whether the user has the appropriate permissions to upload anyway
        $permission = $this->mUpload->isAllowed( $user );

        if ( $permission !== true ) {
            if ( !$user->isLoggedIn() ) {
                $this->dieUsageMsg( array( 'mustbeloggedin', 'upload' ) );
            } else {
                $this->dieUsageMsg( 'badaccess-groups' );
            }
        }
    }

    protected function verifyUpload() {
        $verification = $this->mUpload->verifyUpload();
        if ( $verification['status'] === UploadBase::OK ) {
            return;
        }

        $this->checkVerification( $verification );
    }

    protected function checkVerification( array $verification ) {
        global $wgFileExtensions;

        // @todo Move them to ApiBase's message map
        switch ( $verification['status'] ) {
            // Recoverable errors
            case UploadBase::MIN_LENGTH_PARTNAME:
                $this->dieRecoverableError( 'filename-tooshort', 'filename' );
                break;
            case UploadBase::ILLEGAL_FILENAME:
                $this->dieRecoverableError( 'illegal-filename', 'filename',
                        array( 'filename' => $verification['filtered'] ) );
                break;
            case UploadBase::FILENAME_TOO_LONG:
                $this->dieRecoverableError( 'filename-toolong', 'filename' );
                break;
            case UploadBase::FILETYPE_MISSING:
                $this->dieRecoverableError( 'filetype-missing', 'filename' );
                break;
            case UploadBase::WINDOWS_NONASCII_FILENAME:
                $this->dieRecoverableError( 'windows-nonascii-filename', 'filename' );
                break;

            // Unrecoverable errors
            case UploadBase::EMPTY_FILE:
                $this->dieUsage( 'The file you submitted was empty', 'empty-file' );
                break;
            case UploadBase::FILE_TOO_LARGE:
                $this->dieUsage( 'The file you submitted was too large', 'file-too-large' );
                break;

            case UploadBase::FILETYPE_BADTYPE:
                $extradata = array(
                    'filetype' => $verification['finalExt'],
                    'allowed' => array_values( array_unique( $wgFileExtensions ) )
                );
                $this->getResult()->setIndexedTagName( $extradata['allowed'], 'ext' );

                $msg = "Filetype not permitted: ";
                if ( isset( $verification['blacklistedExt'] ) ) {
                    $msg .= join( ', ', $verification['blacklistedExt'] );
                    $extradata['blacklisted'] = array_values( $verification['blacklistedExt'] );
                    $this->getResult()->setIndexedTagName( $extradata['blacklisted'], 'ext' );
                } else {
                    $msg .= $verification['finalExt'];
                }
                $this->dieUsage( $msg, 'filetype-banned', 0, $extradata );
                break;
            case UploadBase::VERIFICATION_ERROR:
                $this->getResult()->setIndexedTagName( $verification['details'], 'detail' );
                $this->dieUsage( 'This file did not pass file verification', 'verification-error',
                        0, array( 'details' => $verification['details'] ) );
                break;
            case UploadBase::HOOK_ABORTED:
                $this->dieUsage( "The modification you tried to make was aborted by an extension hook",
                        'hookaborted', 0, array( 'error' => $verification['error'] ) );
                break;
            default:
                $this->dieUsage( 'An unknown error occurred', 'unknown-error',
                        0, array( 'code' => $verification['status'] ) );
                break;
        }
    }

    protected function getApiWarnings() {
        $warnings = $this->mUpload->checkWarnings();

        return $this->transformWarnings( $warnings );
    }

    protected function transformWarnings( $warnings ) {
        if ( $warnings ) {
            // Add indices
            $result = $this->getResult();
            $result->setIndexedTagName( $warnings, 'warning' );

            if ( isset( $warnings['duplicate'] ) ) {
                $dupes = array();
                foreach ( $warnings['duplicate'] as $dupe ) {
                    $dupes[] = $dupe->getName();
                }
                $result->setIndexedTagName( $dupes, 'duplicate' );
                $warnings['duplicate'] = $dupes;
            }

            if ( isset( $warnings['exists'] ) ) {
                $warning = $warnings['exists'];
                unset( $warnings['exists'] );
                $localFile = isset( $warning['normalizedFile'] ) ? $warning['normalizedFile'] : $warning['file'];
                $warnings[$warning['warning']] = $localFile->getName();
            }
        }
        return $warnings;
    }

    protected function performUpload( $warnings ) {
        // Use comment as initial page text by default
        if ( is_null( $this->mParams['text'] ) ) {
            $this->mParams['text'] = $this->mParams['comment'];
        }

        $file = $this->mUpload->getLocalFile();
        $watch = $this->getWatchlistValue( $this->mParams['watchlist'], $file->getTitle() );

        // Deprecated parameters
        if ( $this->mParams['watch'] ) {
            $watch = true;
        }

        // No errors, no warnings: do the upload
        if ( $this->mParams['async'] ) {
            $progress = UploadBase::getSessionStatus( $this->mParams['filekey'] );
            if ( $progress && $progress['result'] === 'Poll' ) {
                $this->dieUsage( "Upload from stash already in progress.", 'publishfailed' );
            }
            UploadBase::setSessionStatus(
                $this->mParams['filekey'],
                array( 'result' => 'Poll', 'stage' => 'queued', 'status' => Status::newGood() )
            );
            $ok = JobQueueGroup::singleton()->push( new PublishStashedFileJob(
                Title::makeTitle( NS_FILE, $this->mParams['filename'] ),
                array(
                    'filename' => $this->mParams['filename'],
                    'filekey' => $this->mParams['filekey'],
                    'comment' => $this->mParams['comment'],
                    'text' => $this->mParams['text'],
                    'watch' => $watch,
                    'session' => $this->getContext()->exportSession()
                )
            ) );
            if ( $ok ) {
                $result['result'] = 'Poll';
            } else {
                UploadBase::setSessionStatus( $this->mParams['filekey'], false );
                $this->dieUsage(
                    "Failed to start PublishStashedFile.php", 'publishfailed' );
            }
        } else {
            $status = $this->mUpload->performUpload( $this->mParams['comment'],
                $this->mParams['text'], $watch, $this->getUser() );

            if ( !$status->isGood() ) {
                $error = $status->getErrorsArray();

                if ( count( $error ) == 1 && $error[0][0] == 'async' ) {
                    // The upload can not be performed right now, because the user
                    // requested so
                    return array(
                        'result' => 'Queued',
                        'statuskey' => $error[0][1],
                    );
                } else {
                    $this->getResult()->setIndexedTagName( $error, 'error' );

                    $this->dieUsage( 'An internal error occurred', 'internal-error', 0, $error );
                }
            }
            $result['result'] = 'Success';
        }

        $result['filename'] = $file->getName();
        if ( $warnings && count( $warnings ) > 0 ) {
            $result['warnings'] = $warnings;
        }

        return $result;
    }

    protected function checkAsyncDownloadEnabled() {
        global $wgAllowAsyncCopyUploads;
        if ( !$wgAllowAsyncCopyUploads ) {
            $this->dieUsage( 'Asynchronous copy uploads disabled', 'asynccopyuploaddisabled' );
        }
    }

    public function mustBePosted() {
        return true;
    }

    public function isWriteMode() {
        return true;
    }

    public function getAllowedParams() {
        $params = array(
            'filename' => array(
                ApiBase::PARAM_TYPE => 'string',
            ),
            'comment' => array(
                ApiBase::PARAM_DFLT => ''
            ),
            'text' => null,
            'token' => array(
                ApiBase::PARAM_TYPE => 'string',
                ApiBase::PARAM_REQUIRED => true
            ),
            'watch' => array(
                ApiBase::PARAM_DFLT => false,
                ApiBase::PARAM_DEPRECATED => true,
            ),
            'watchlist' => array(
                ApiBase::PARAM_DFLT => 'preferences',
                ApiBase::PARAM_TYPE => array(
                    'watch',
                    'preferences',
                    'nochange'
                ),
            ),
            'ignorewarnings' => false,
            'file' => array(
                ApiBase::PARAM_TYPE => 'upload',
            ),
            'url' => null,
            'filekey' => null,
            'sessionkey' => array(
                ApiBase::PARAM_DFLT => null,
                ApiBase::PARAM_DEPRECATED => true,
            ),
            'stash' => false,

            'filesize' => null,
            'offset' => null,
            'chunk' => array(
                ApiBase::PARAM_TYPE => 'upload',
            ),

            'async' => false,
            'asyncdownload' => false,
            'leavemessage' => false,
            'statuskey' => null,
            'checkstatus' => false,
        );

        return $params;
    }

    public function getParamDescription() {
        $params = array(
            'filename' => 'Target filename',
            'token' => 'Edit token. You can get one of these through prop=info',
            'comment' => 'Upload comment. Also used as the initial page text for new files if "text" is not specified',
            'text' => 'Initial page text for new files',
            'watch' => 'Watch the page',
            'watchlist' => 'Unconditionally add or remove the page from your watchlist, use preferences or do not change watch',
            'ignorewarnings' => 'Ignore any warnings',
            'file' => 'File contents',
            'url' => 'URL to fetch the file from',
            'filekey' => 'Key that identifies a previous upload that was stashed temporarily.',
            'sessionkey' => 'Same as filekey, maintained for backward compatibility.',
            'stash' => 'If set, the server will not add the file to the repository and stash it temporarily.',

            'chunk' => 'Chunk contents',
            'offset' => 'Offset of chunk in bytes',
            'filesize' => 'Filesize of entire upload',

            'async' => 'Make potentially large file operations asynchronous when possible',
            'asyncdownload' => 'Make fetching a URL asynchronous',
            'leavemessage' => 'If asyncdownload is used, leave a message on the user talk page if finished',
            'statuskey' => 'Fetch the upload status for this file key (upload by URL)',
            'checkstatus' => 'Only fetch the upload status for the given file key',
        );

        return $params;

    }

    public function getResultProperties() {
        return array(
            '' => array(
                'result' => array(
                    ApiBase::PROP_TYPE => array(
                        'Success',
                        'Warning',
                        'Continue',
                        'Queued'
                    ),
                ),
                'filekey' => array(
                    ApiBase::PROP_TYPE => 'string',
                    ApiBase::PROP_NULLABLE => true
                ),
                'sessionkey' => array(
                    ApiBase::PROP_TYPE => 'string',
                    ApiBase::PROP_NULLABLE => true
                ),
                'offset' => array(
                    ApiBase::PROP_TYPE => 'integer',
                    ApiBase::PROP_NULLABLE => true
                ),
                'statuskey' => array(
                    ApiBase::PROP_TYPE => 'string',
                    ApiBase::PROP_NULLABLE => true
                ),
                'filename' => array(
                    ApiBase::PROP_TYPE => 'string',
                    ApiBase::PROP_NULLABLE => true
                )
            )
        );
    }

    public function getDescription() {
        return array(
            'Upload a file, or get the status of pending uploads. Several methods are available:',
            ' * Upload file contents directly, using the "file" parameter',
            ' * Have the MediaWiki server fetch a file from a URL, using the "url" parameter',
            ' * Complete an earlier upload that failed due to warnings, using the "filekey" parameter',
            'Note that the HTTP POST must be done as a file upload (i.e. using multipart/form-data) when',
            'sending the "file". Also you must get and send an edit token before doing any upload stuff'
        );
    }

    public function getPossibleErrors() {
        return array_merge( parent::getPossibleErrors(),
            $this->getRequireOnlyOneParameterErrorMessages( array( 'filekey', 'file', 'url', 'statuskey' ) ),
            array(
                array( 'uploaddisabled' ),
                array( 'invalid-file-key' ),
                array( 'uploaddisabled' ),
                array( 'mustbeloggedin', 'upload' ),
                array( 'badaccess-groups' ),
                array( 'code' => 'fetchfileerror', 'info' => '' ),
                array( 'code' => 'nomodule', 'info' => 'No upload module set' ),
                array( 'code' => 'empty-file', 'info' => 'The file you submitted was empty' ),
                array( 'code' => 'filetype-missing', 'info' => 'The file is missing an extension' ),
                array( 'code' => 'filename-tooshort', 'info' => 'The filename is too short' ),
                array( 'code' => 'overwrite', 'info' => 'Overwriting an existing file is not allowed' ),
                array( 'code' => 'stashfailed', 'info' => 'Stashing temporary file failed' ),
                array( 'code' => 'publishfailed', 'info' => 'Publishing of stashed file failed' ),
                array( 'code' => 'internal-error', 'info' => 'An internal error occurred' ),
                array( 'code' => 'asynccopyuploaddisabled', 'info' => 'Asynchronous copy uploads disabled' ),
                array( 'code' => 'stasherror', 'info' => 'An upload stash error occurred' ),
                array( 'fileexists-forbidden' ),
                array( 'fileexists-shared-forbidden' ),
            )
        );
    }

    public function needsToken() {
        return true;
    }

    public function getTokenSalt() {
        return '';
    }

    public function getExamples() {
        return array(
            'api.php?action=upload&filename=Wiki.png&url=http%3A//upload.wikimedia.org/wikipedia/en/b/bc/Wiki.png'
                => 'Upload from a URL',
            'api.php?action=upload&filename=Wiki.png&filekey=filekey&ignorewarnings=1'
                => 'Complete an upload that failed due to warnings',
        );
    }

    public function getHelpUrls() {
        return 'https://www.mediawiki.org/wiki/API:Upload';
    }
}