MOBILE-2939 offline: Improve download confirm and error messages.

src/core/constants.ts

@@ -23,6 +23,8 @@ export class CoreConstants {
     static SECONDS_MINUTE = 60;
     static WIFI_DOWNLOAD_THRESHOLD = 104857600; // 100MB.
     static DOWNLOAD_THRESHOLD = 10485760; // 10MB.
+    static MINIMUM_FREE_SPACE = 10485760; // 10MB.
+    static IOS_FREE_SPACE_THRESHOLD = 524288000; // 500MB.
     static DONT_SHOW_ERROR = 'CoreDontShowError';
     static NO_SITE_ID = 'NoSite';
 

src/core/course/lang/en.json

@@ -4,10 +4,12 @@
     "activitynotyetviewablesiteupgradeneeded": "Your organisation's Moodle installation needs to be updated.",
     "allsections": "All sections",
     "askadmintosupport": "Contact the site administrator and tell them you want to use this activity with the Moodle Mobile app.",
+    "availablespace": " You currently have about {{available}} free space.",
     "confirmdeletemodulefiles": "Are you sure you want to delete these files?",
-    "confirmdownload": "You are about to download {{size}}. Are you sure you want to continue?",
+    "confirmdownload": "You are about to download {{size}}.{{availableSpace}} Are you sure you want to continue?",
-    "confirmdownloadunknownsize": "It was not possible to calculate the size of the download. Are you sure you want to continue?",
+    "confirmdownloadunknownsize": "It was not possible to calculate the size of the download.{{availableSpace}} Are you sure you want to continue?",
-    "confirmpartialdownloadsize": "You are about to download <strong>at least</strong> {{size}}. Are you sure you want to continue?",
+    "confirmpartialdownloadsize": "You are about to download <strong>at least</strong> {{size}}.{{availableSpace}} Are you sure you want to continue?",
+    "confirmlimiteddownload": "You are not currently connected to WiFi. ",
     "contents": "Contents",
     "couldnotloadsectioncontent": "Could not load the section content. Please try again later.",
     "couldnotloadsections": "Could not load the sections. Please try again later.",
@@ -18,6 +20,8 @@
     "errorgetmodule": "Error getting activity data.",
     "hiddenfromstudents": "Hidden from students",
     "hiddenoncoursepage": "Available but not shown on course page",
+    "insufficientavailablespace": "You are trying to download {{size}}. This will leave your device with insufficient space to operate normally. Please clear some storage space first.",
+    "insufficientavailablequota": "Your device could not allocate space to save this download. It may be reserving space for app and system updates. Please clear some storage space first.",
     "manualcompletionnotsynced": "Manual completion not synchronised.",
     "nocontentavailable": "No content available at the moment.",
     "overriddennotice": "Your final grade from this activity was manually adjusted.",

src/providers/filepool.ts

@@ -1122,10 +1122,10 @@ export class CoreFilepoolProvider {
             return Promise.all(promises).then(() => {
                 // Success prefetching, store package as downloaded.
                 return this.storePackageStatus(siteId, CoreConstants.DOWNLOADED, component, componentId, extra);
-            }).catch(() => {
+            }).catch((error) => {
                 // Error downloading, go back to previous status and reject the promise.
                 return this.setPackagePreviousStatus(siteId, component, componentId).then(() => {
-                    return Promise.reject(null);
+                    return Promise.reject(error);
                 });
             });
 
@@ -2566,18 +2566,26 @@ export class CoreFilepoolProvider {
                     dropFromQueue = true;
                 }
 
+                let errorMessage = null;
+                // Some Android devices restrict the amount of usable storage using quotas.
+                // If this quota would be exceeded by the download, it throws an exception.
+                // We catch this exception here, and report a meaningful error message to the user.
+                if (errorObject instanceof FileTransferError && errorObject.exception.includes('EDQUOT')) {
+                    errorMessage = 'core.course.insufficientavailablequota';
+                }
+
                 if (dropFromQueue) {
                     this.logger.debug('Item dropped from queue due to error: ' + fileUrl, errorObject);
 
                     return this.removeFromQueue(siteId, fileId).catch(() => {
                         // Consider this as a silent error, never reject the promise here.
                     }).then(() => {
-                        this.treatQueueDeferred(siteId, fileId, false);
+                        this.treatQueueDeferred(siteId, fileId, false, errorMessage);
                         this.notifyFileDownloadError(siteId, fileId);
                     });
                 } else {
                     // We considered the file as legit but did not get it, failure.
-                    this.treatQueueDeferred(siteId, fileId, false);
+                    this.treatQueueDeferred(siteId, fileId, false, errorMessage);
                     this.notifyFileDownloadError(siteId, fileId);
 
                     return Promise.reject(errorObject);
@@ -2912,13 +2920,14 @@ export class CoreFilepoolProvider {
      * @param {string} siteId The site ID.
      * @param {string} fileId The file ID.
      * @param {boolean} resolve True if promise should be resolved, false if it should be rejected.
+     * @param {string} error String identifier for error message, if rejected.
      */
-    protected treatQueueDeferred(siteId: string, fileId: string, resolve: boolean): void {
+    protected treatQueueDeferred(siteId: string, fileId: string, resolve: boolean, error?: string): void {
         if (this.queueDeferreds[siteId] && this.queueDeferreds[siteId][fileId]) {
             if (resolve) {
                 this.queueDeferreds[siteId][fileId].resolve();
             } else {
-                this.queueDeferreds[siteId][fileId].reject();
+                this.queueDeferreds[siteId][fileId].reject(error);
             }
             delete this.queueDeferreds[siteId][fileId];
         }

src/providers/utils/dom.ts

@@ -23,6 +23,7 @@ import { CoreTextUtilsProvider } from './text';
 import { CoreAppProvider } from '../app';
 import { CoreConfigProvider } from '../config';
 import { CoreUrlUtilsProvider } from './url';
+import { CoreFileProvider } from '@providers/file';
 import { CoreConstants } from '@core/constants';
 import { CoreBSTooltipComponent } from '@components/bs-tooltip/bs-tooltip';
 import { Md5 } from 'ts-md5/dist/md5';
@@ -66,7 +67,8 @@ export class CoreDomUtilsProvider {
     constructor(private translate: TranslateService, private loadingCtrl: LoadingController, private toastCtrl: ToastController,
             private alertCtrl: AlertController, private textUtils: CoreTextUtilsProvider, private appProvider: CoreAppProvider,
             private platform: Platform, private configProvider: CoreConfigProvider, private urlUtils: CoreUrlUtilsProvider,
-            private modalCtrl: ModalController, private sanitizer: DomSanitizer, private popoverCtrl: PopoverController) {
+            private modalCtrl: ModalController, private sanitizer: DomSanitizer, private popoverCtrl: PopoverController,
+            private fileProvider: CoreFileProvider) {
 
         // Check if debug messages should be displayed.
         configProvider.get(CoreConstants.SETTINGS_DEBUG_DISPLAY, false).then((debugDisplay) => {
@@ -128,28 +130,73 @@ export class CoreDomUtilsProvider {
      */
     confirmDownloadSize(size: any, message?: string, unknownMessage?: string, wifiThreshold?: number, limitedThreshold?: number,
             alwaysConfirm?: boolean): Promise<void> {
+        const readableSize = this.textUtils.bytesToSize(size.size, 2);
+
+        const getAvailableBytes = new Promise((resolve): void => {
+            if (this.appProvider.isDesktop()) {
+                // Free space calculation is not supported on desktop.
+                resolve(null);
+            } else {
+                this.fileProvider.calculateFreeSpace().then((availableBytes) => {
+                    if (this.platform.is('android')) {
+                        return availableBytes;
+                    } else {
+                        // Space calculation is not accurate on iOS, but it gets more accurate when space is lower.
+                        // We'll only use it when space is <500MB, or we're downloading more than twice the reported space.
+                        if (availableBytes < CoreConstants.IOS_FREE_SPACE_THRESHOLD || size.size > availableBytes / 2) {
+                            return availableBytes;
+                        } else {
+                            return null;
+                        }
+                    }
+                }).then((availableBytes) => {
+                    resolve(availableBytes);
+                });
+            }
+        });
+
+        const getAvailableSpace = getAvailableBytes.then((availableBytes: number) => {
+            if (availableBytes === null) {
+                return '';
+            } else {
+                const availableSize = this.textUtils.bytesToSize(availableBytes, 2);
+                if (this.platform.is('android') && size.size > availableBytes - CoreConstants.MINIMUM_FREE_SPACE) {
+                    return Promise.reject(this.translate.instant('core.course.insufficientavailablespace', { size: readableSize }));
+                }
+
+                return this.translate.instant('core.course.availablespace', {available: availableSize});
+            }
+        });
+
+        return getAvailableSpace.then((availableSpace) => {
             wifiThreshold = typeof wifiThreshold == 'undefined' ? CoreConstants.WIFI_DOWNLOAD_THRESHOLD : wifiThreshold;
             limitedThreshold = typeof limitedThreshold == 'undefined' ? CoreConstants.DOWNLOAD_THRESHOLD : limitedThreshold;
 
+            let wifiPrefix = '';
+            if (this.appProvider.isNetworkAccessLimited()) {
+                wifiPrefix = this.translate.instant('core.course.confirmlimiteddownload');
+            }
+
             if (size.size < 0 || (size.size == 0 && !size.total)) {
                 // Seems size was unable to be calculated. Show a warning.
                 unknownMessage = unknownMessage || 'core.course.confirmdownloadunknownsize';
 
-            return this.showConfirm(this.translate.instant(unknownMessage));
+                return this.showConfirm(wifiPrefix + this.translate.instant(unknownMessage, {availableSpace: availableSpace}));
             } else if (!size.total) {
                 // Filesize is only partial.
-            const readableSize = this.textUtils.bytesToSize(size.size, 2);
 
-            return this.showConfirm(this.translate.instant('core.course.confirmpartialdownloadsize', { size: readableSize }));
+                return this.showConfirm(wifiPrefix + this.translate.instant('core.course.confirmpartialdownloadsize',
+                    { size: readableSize, availableSpace: availableSpace }));
             } else if (alwaysConfirm || size.size >= wifiThreshold ||
                 (this.appProvider.isNetworkAccessLimited() && size.size >= limitedThreshold)) {
                 message = message || 'core.course.confirmdownload';
-            const readableSize = this.textUtils.bytesToSize(size.size, 2);
 
-            return this.showConfirm(this.translate.instant(message, { size: readableSize }));
+                return this.showConfirm(wifiPrefix + this.translate.instant(message,
+                    { size: readableSize, availableSpace: availableSpace }));
             }
 
             return Promise.resolve();
+        });
     }
 
     /**

src/providers/utils/text.ts

@@ -113,7 +113,7 @@ export class CoreTextUtilsProvider {
      */
     bytesToSize(bytes: number, precision: number = 2): string {
 
-        if (typeof bytes == 'undefined' || bytes < 0) {
+        if (typeof bytes == 'undefined' || bytes === null || bytes < 0) {
             return this.translate.instant('core.notapplicable');
         }