// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* The course file uploader.
*
* This module is used to upload files directly into the course.
*
* @module core_courseformat/local/courseeditor/fileuploader
* @copyright 2022 Ferran Recio <ferran@moodle.com>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
/**
* @typedef {Object} Handler
* @property {String} extension the handled extension or * for any
* @property {String} message the handler message
* @property {String} module the module name
*/
import Config from 'core/config';
import ModalSaveCancel from 'core/modal_save_cancel';
import ModalEvents from 'core/modal_events';
import Templates from 'core/templates';
import {getFirst} from 'core/normalise';
import {prefetchStrings} from 'core/prefetch';
import {getString, getStrings} from 'core/str';
import {getCourseEditor} from 'core_courseformat/courseeditor';
import {processMonitor} from 'core/process_monitor';
import {debounce} from 'core/utils';
// Uploading url.
const UPLOADURL = Config.wwwroot + '/course/dndupload.php';
const DEBOUNCETIMER = 500;
const USERCANIGNOREFILESIZELIMITS = -1;
/** @var {ProcessQueue} uploadQueue the internal uploadQueue instance. */
let uploadQueue = null;
/** @var {Object} handlerManagers the courseId indexed loaded handler managers. */
let handlerManagers = {};
/** @var {Map} courseUpdates the pending course sections updates. */
let courseUpdates = new Map();
/** @var {Object} errors the error messages. */
let errors = null;
// Load global strings.
prefetchStrings('moodle', ['addresourceoractivity', 'upload']);
prefetchStrings('core_error', ['dndmaxbytes', 'dndread', 'dndupload', 'dndunkownfile']);
/**
* Class to upload a file into the course.
* @private
*/
class FileUploader {
/**
* Class constructor.
*
* @param {number} courseId the course id
* @param {number} sectionId the section id
* @param {number} sectionNum the section number
* @param {File} fileInfo the file information object
* @param {Handler} handler the file selected file handler
*/
constructor(courseId, sectionId, sectionNum, fileInfo, handler) {
this.courseId = courseId;
this.sectionId = sectionId;
this.sectionNum = sectionNum;
this.fileInfo = fileInfo;
this.handler = handler;
}
/**
* Execute the file upload and update the state in the given process.
*
* @param {LoadingProcess} process the process to store the upload result
*/
execute(process) {
const fileInfo = this.fileInfo;
const xhr = this._createXhrRequest(process);
const formData = this._createUploadFormData();
// Try reading the file to check it is not a folder, before sending it to the server.
const reader = new FileReader();
reader.onload = function() {
// File was read OK - send it to the server.
xhr.open("POST", UPLOADURL, true);
xhr.send(formData);
};
reader.onerror = function() {
// Unable to read the file (it is probably a folder) - display an error message.
process.setError(errors.dndread);
};
if (fileInfo.size > 0) {
// If this is a non-empty file, try reading the first few bytes.
// This will trigger reader.onerror() for folders and reader.onload() for ordinary, readable files.
reader.readAsText(fileInfo.slice(0, 5));
} else {
// If you call slice() on a 0-byte folder, before calling readAsText, then Firefox triggers reader.onload(),
// instead of reader.onerror().
// So, for 0-byte files, just call readAsText on the whole file (and it will trigger load/error functions as expected).
reader.readAsText(fileInfo);
}
}
/**
* Returns the bind version of execute function.
*
* This method is used to queue the process into a ProcessQueue instance.
*
* @returns {Function} the bind function to execute the process
*/
getExecutionFunction() {
return this.execute.bind(this);
}
/**
* Generate a upload XHR file request.
*
* @param {LoadingProcess} process the current process
* @return {XMLHttpRequest} the XHR request
*/
_createXhrRequest(process) {
const xhr = new XMLHttpRequest();
// Update the progress bar as the file is uploaded.
xhr.upload.addEventListener(
'progress',
(event) => {
if (event.lengthComputable) {
const percent = Math.round((event.loaded * 100) / event.total);
process.setPercentage(percent);
}
},
false
);
// Wait for the AJAX call to complete.
xhr.onreadystatechange = () => {
if (xhr.readyState == 1) {
// Add a 1% just to indicate that it is uploading.
process.setPercentage(1);
}
// State 4 is DONE. Otherwise the connection is still ongoing.
if (xhr.readyState != 4) {
return;
}
if (xhr.status == 200) {
var result = JSON.parse(xhr.responseText);
if (result && result.error == 0) {
// All OK.
this._finishProcess(process);
} else {
process.setError(result.error);
}
} else {
process.setError(errors.dndupload);
}
};
return xhr;
}
/**
* Upload a file into the course.
*
* @return {FormData|null} the new form data object
*/
_createUploadFormData() {
const formData = new FormData();
try {
formData.append('repo_upload_file', this.fileInfo);
} catch (error) {
throw Error(error.dndread);
}
formData.append('sesskey', Config.sesskey);
formData.append('course', this.courseId);
formData.append('section', this.sectionNum);
formData.append('module', this.handler.module);
formData.append('type', 'Files');
return formData;
}
/**
* Finishes the current process.
* @param {LoadingProcess} process the process
*/
_finishProcess(process) {
addRefreshSection(this.courseId, this.sectionId);
process.setPercentage(100);
process.finish();
}
}
/**
* The file handler manager class.
*
* @private
*/
class HandlerManager {
/** @var {Object} lastHandlers the last handlers selected per each file extension. */
lastHandlers = {};
/** @var {Handler[]|null} allHandlers all the available handlers. */
allHandlers = null;
/**
* Class constructor.
*
* @param {Number} courseId
*/
constructor(courseId) {
this.courseId = courseId;
this.lastUploadId = 0;
this.courseEditor = getCourseEditor(courseId);
if (!this.courseEditor) {
throw Error('Unkown course editor');
}
this.maxbytes = this.courseEditor.get('course')?.maxbytes ?? 0;
}
/**
* Load the course file handlers.
*/
async loadHandlers() {
this.allHandlers = await this.courseEditor.getFileHandlersPromise();
}
/**
* Extract the file extension from a fileInfo.
*
* @param {File} fileInfo
* @returns {String} the file extension or an empty string.
*/
getFileExtension(fileInfo) {
let extension = '';
const dotpos = fileInfo.name.lastIndexOf('.');
if (dotpos != -1) {
extension = fileInfo.name.substring(dotpos + 1, fileInfo.name.length).toLowerCase();
}
return extension;
}
/**
* Check if the file is valid.
*
* @param {File} fileInfo the file info
*/
validateFile(fileInfo) {
if (this.maxbytes !== USERCANIGNOREFILESIZELIMITS && fileInfo.size > this.maxbytes) {
throw Error(errors.dndmaxbytes);
}
}
/**
* Get the file handlers of an specific file.
*
* @param {File} fileInfo the file indo
* @return {Array} Array of handlers
*/
filterHandlers(fileInfo) {
const extension = this.getFileExtension(fileInfo);
return this.allHandlers.filter(handler => handler.extension == '*' || handler.extension == extension);
}
/**
* Get the Handler to upload a specific file.
*
* It will ask the used if more than one handler is available.
*
* @param {File} fileInfo the file info
* @returns {Promise<Handler|null>} the selected handler or null if the user cancel
*/
async getFileHandler(fileInfo) {
const fileHandlers = this.filterHandlers(fileInfo);
if (fileHandlers.length == 0) {
throw Error(errors.dndunkownfile);
}
let fileHandler = null;
if (fileHandlers.length == 1) {
fileHandler = fileHandlers[0];
} else {
fileHandler = await this.askHandlerToUser(fileHandlers, fileInfo);
}
return fileHandler;
}
/**
* Ask the user to select a specific handler.
*
* @param {Handler[]} fileHandlers
* @param {File} fileInfo the file info
* @return {Promise<Handler>} the selected handler
*/
async askHandlerToUser(fileHandlers, fileInfo) {
const extension = this.getFileExtension(fileInfo);
// Build the modal parameters from the event data.
const modalParams = {
title: getString('addresourceoractivity', 'moodle'),
body: Templates.render(
'core_courseformat/fileuploader',
this.getModalData(
fileHandlers,
fileInfo,
this.lastHandlers[extension] ?? null
)
),
saveButtonText: getString('upload', 'moodle'),
};
// Create the modal.
const modal = await this.modalBodyRenderedPromise(modalParams);
const selectedHandler = await this.modalUserAnswerPromise(modal, fileHandlers);
// Cancel action.
if (selectedHandler === null) {
return null;
}
// Save last selected handler.
this.lastHandlers[extension] = selectedHandler.module;
return selectedHandler;
}
/**
* Generated the modal template data.
*
* @param {Handler[]} fileHandlers
* @param {File} fileInfo the file info
* @param {String|null} defaultModule the default module if any
* @return {Object} the modal template data.
*/
getModalData(fileHandlers, fileInfo, defaultModule) {
const data = {
filename: fileInfo.name,
uploadid: ++this.lastUploadId,
handlers: [],
};
let hasDefault = false;
fileHandlers.forEach((handler, index) => {
const isDefault = (defaultModule == handler.module);
const optionNumber = index + 1;
data.handlers.push({
...handler,
selected: isDefault,
labelid: `fileuploader_${data.uploadid}_${optionNumber}`,
value: index,
});
hasDefault = hasDefault || isDefault;
});
if (!hasDefault && data.handlers.length > 0) {
const lastHandler = data.handlers.pop();
lastHandler.selected = true;
data.handlers.push(lastHandler);
}
return data;
}
/**
* Get the user handler choice.
*
* Wait for the user answer in the modal and resolve with the selected index.
*
* @param {Modal} modal the modal instance
* @param {Handler[]} fileHandlers the availabvle file handlers
* @return {Promise} with the option selected by the user.
*/
modalUserAnswerPromise(modal, fileHandlers) {
const modalBody = getFirst(modal.getBody());
return new Promise((resolve, reject) => {
modal.getRoot().on(
ModalEvents.save,
event => {
// Get the selected option.
const index = modalBody.querySelector('input:checked').value;
event.preventDefault();
modal.destroy();
if (!fileHandlers[index]) {
reject('Invalid handler selected');
}
resolve(fileHandlers[index]);
}
);
modal.getRoot().on(
ModalEvents.cancel,
() => {
resolve(null);
}
);
});
}
/**
* Create a new modal and return a Promise to the body rendered.
*
* @param {Object} modalParams the modal params
* @returns {Promise} the modal body rendered promise
*/
modalBodyRenderedPromise(modalParams) {
return new Promise((resolve, reject) => {
ModalSaveCancel.create(modalParams).then((modal) => {
modal.setRemoveOnClose(true);
// Handle body loading event.
modal.getRoot().on(ModalEvents.bodyRendered, () => {
resolve(modal);
});
// Configure some extra modal params.
if (modalParams.saveButtonText !== undefined) {
modal.setSaveButtonText(modalParams.saveButtonText);
}
modal.show();
return;
}).catch(() => {
reject(`Cannot load modal content`);
});
});
}
}
/**
* Add a section to refresh.
*
* @param {number} courseId the course id
* @param {number} sectionId the seciton id
*/
function addRefreshSection(courseId, sectionId) {
let refresh = courseUpdates.get(courseId);
if (!refresh) {
refresh = new Set();
}
refresh.add(sectionId);
courseUpdates.set(courseId, refresh);
refreshCourseEditors();
}
/**
* Debounced processing all pending course refreshes.
* @private
*/
const refreshCourseEditors = debounce(
() => {
const refreshes = courseUpdates;
courseUpdates = new Map();
refreshes.forEach((sectionIds, courseId) => {
const courseEditor = getCourseEditor(courseId);
if (!courseEditor) {
return;
}
courseEditor.dispatch('sectionState', [...sectionIds]);
});
},
DEBOUNCETIMER
);
/**
* Load and return the course handler manager instance.
*
* @param {Number} courseId the course Id to load
* @returns {Promise<HandlerManager>} promise of the the loaded handleManager
*/
async function loadCourseHandlerManager(courseId) {
if (handlerManagers[courseId] !== undefined) {
return handlerManagers[courseId];
}
const handlerManager = new HandlerManager(courseId);
await handlerManager.loadHandlers();
handlerManagers[courseId] = handlerManager;
return handlerManagers[courseId];
}
/**
* Load all the erros messages at once in the module "errors" variable.
* @param {Number} courseId the course id
*/
async function loadErrorStrings(courseId) {
if (errors !== null) {
return;
}
const courseEditor = getCourseEditor(courseId);
const maxbytestext = courseEditor.get('course')?.maxbytestext ?? '0';
errors = {};
const allStrings = [
{key: 'dndmaxbytes', component: 'core_error', param: {size: maxbytestext}},
{key: 'dndread', component: 'core_error'},
{key: 'dndupload', component: 'core_error'},
{key: 'dndunkownfile', component: 'core_error'},
];
const loadedStrings = await getStrings(allStrings);
allStrings.forEach(({key}, index) => {
errors[key] = loadedStrings[index];
});
}
/**
* Start a batch file uploading into the course.
*
* @private
* @param {number} courseId the course id.
* @param {number} sectionId the section id.
* @param {number} sectionNum the section number.
* @param {File} fileInfo the file information object
* @param {HandlerManager} handlerManager the course handler manager
*/
const queueFileUpload = async function(courseId, sectionId, sectionNum, fileInfo, handlerManager) {
let handler;
uploadQueue = await processMonitor.createProcessQueue();
try {
handlerManager.validateFile(fileInfo);
handler = await handlerManager.getFileHandler(fileInfo);
} catch (error) {
uploadQueue.addError(fileInfo.name, error.message);
return;
}
// If we don't have a handler means the user cancel the upload.
if (!handler) {
return;
}
const fileProcessor = new FileUploader(courseId, sectionId, sectionNum, fileInfo, handler);
uploadQueue.addPending(fileInfo.name, fileProcessor.getExecutionFunction());
};
/**
* Upload a file to the course.
*
* This method will show any necesary modal to handle the request.
*
* @param {number} courseId the course id
* @param {number} sectionId the section id
* @param {number} sectionNum the section number
* @param {Array} files and array of files
*/
export const uploadFilesToCourse = async function(courseId, sectionId, sectionNum, files) {
// Get the course handlers.
const handlerManager = await loadCourseHandlerManager(courseId);
await loadErrorStrings(courseId);
for (let index = 0; index < files.length; index++) {
const fileInfo = files[index];
await queueFileUpload(courseId, sectionId, sectionNum, fileInfo, handlerManager);
}
};