MOBILE-3855 course: Fix length of undefined error in hidden modules

src/addons/mod/book/components/index/index.ts

@@ -133,8 +133,11 @@ export class AddonModBookIndexComponent extends CoreCourseModuleMainResourceComp
 
             await this.loadBookData();
 
-            this.contentsMap = AddonModBook.getContentsMap(this.module.contents);
+            // Get contents. No need to refresh, it has been done in downloadResourceIfNeeded.
-            this.chapters = AddonModBook.getTocList(this.module.contents);
+            const contents = await CoreCourse.getModuleContents(this.module, this.courseId);
+
+            this.contentsMap = AddonModBook.getContentsMap(contents);
+            this.chapters = AddonModBook.getTocList(contents);
 
             if (typeof this.currentChapter == 'undefined' && typeof this.initialChapterId != 'undefined' && this.chapters) {
                 // Initial chapter set. Validate that the chapter exists.

src/addons/mod/folder/components/index/addon-mod-folder-index.html

@@ -34,8 +34,8 @@
         contextLevel="module" [contextInstanceId]="module.id" [courseId]="courseId">
     </core-course-module-description>
 
-    <ion-list *ngIf="contents && (contents!.files.length + contents!.folders.length > 0)">
+    <ion-list *ngIf="contents && (contents.files.length + contents.folders.length > 0)">
-        <ng-container *ngFor="let folder of contents!.folders">
+        <ng-container *ngFor="let folder of contents.folders">
             <ion-item class="item-file" (click)="openFolder(folder)" detail="true" button>
                 <ion-icon name="fas-folder" slot="start" [attr.aria-label]="'core.folder' | translate"></ion-icon>
                 <ion-label>
@@ -43,12 +43,12 @@
                 </ion-label>
             </ion-item>
         </ng-container>
-        <ng-container *ngFor="let file of contents!.files">
+        <ng-container *ngFor="let file of contents.files">
             <core-file [file]="file" [component]="component" [componentId]="componentId"></core-file>
         </ng-container>
     </ion-list>
 
-    <core-empty-box *ngIf="!contents || (contents!.files.length + contents!.folders.length == 0)" icon="far-folder-open"
+    <core-empty-box *ngIf="!contents || (contents.files.length + contents.folders.length == 0)" icon="far-folder-open"
         [message]=" 'addon.mod_folder.emptyfilelist' | translate"></core-empty-box>
 
 </core-loading>

src/addons/mod/folder/components/index/index.ts

@@ -95,12 +95,13 @@ export class AddonModFolderIndexComponent extends CoreCourseModuleMainResourceCo
     protected async fetchContent(refresh = false): Promise<void> {
         try {
             this.folderInstance = await AddonModFolder.getFolder(this.courseId, this.module.id);
-            await CoreCourse.loadModuleContents(this.module, this.courseId, undefined, false, refresh);
+
+            const contents = await CoreCourse.getModuleContents(this.module, this.courseId, undefined, false, refresh);
 
             this.dataRetrieved.emit(this.folderInstance || this.module);
 
             this.description = this.folderInstance ? this.folderInstance.intro : this.module.description;
-            this.contents = AddonModFolderHelper.formatContents(this.module.contents);
+            this.contents = AddonModFolderHelper.formatContents(contents);
         } finally {
             this.fillContextMenu(refresh);
         }

src/addons/mod/imscp/components/index/index.ts

@@ -85,7 +85,10 @@ export class AddonModImscpIndexComponent extends CoreCourseModuleMainResourceCom
             this.description = imscp.intro;
             this.dataRetrieved.emit(imscp);
 
-            this.items = AddonModImscp.createItemList(this.module.contents);
+            // Get contents. No need to refresh, it has been done in downloadResourceIfNeeded.
+            const contents = await CoreCourse.getModuleContents(this.module, this.courseId);
+
+            this.items = AddonModImscp.createItemList(contents);
 
             if (this.items.length && typeof this.currentItem == 'undefined') {
                 this.currentItem = this.items[0].href;

src/addons/mod/imscp/services/imscp.ts

@@ -229,8 +229,10 @@ export class AddonModImscpProvider {
      * @return Promise resolved with the item src.
      */
     async getIframeSrc(module: CoreCourseModule, itemHref?: string): Promise<string> {
+        const contents = await CoreCourse.getModuleContents(module);
+
         if (!itemHref) {
-            const toc = this.getToc(module.contents);
+            const toc = this.getToc(contents);
             if (!toc.length) {
                 throw new CoreError('Empty TOC');
             }
@@ -246,7 +248,7 @@ export class AddonModImscpProvider {
         } catch (error) {
             // Error getting directory, there was an error downloading or we're in browser. Return online URL if connected.
             if (CoreApp.isOnline()) {
-                const indexUrl = this.getFileUrlFromContents(module.contents, itemHref);
+                const indexUrl = this.getFileUrlFromContents(contents, itemHref);
 
                 if (indexUrl) {
                     const site = await CoreSites.getSite(siteId);

src/addons/mod/page/components/index/index.ts

@@ -81,9 +81,12 @@ export class AddonModPageIndexComponent extends CoreCourseModuleMainResourceComp
             // Download the resource if it needs to be downloaded.
             const downloadResult = await this.downloadResourceIfNeeded(refresh);
 
+            // Get contents. No need to refresh, it has been done in downloadResourceIfNeeded.
+            const contents = await CoreCourse.getModuleContents(this.module, this.courseId);
+
             const results = await Promise.all([
                 this.loadPageData(),
-                AddonModPageHelper.getPageHtml(this.module.contents, this.module.id),
+                AddonModPageHelper.getPageHtml(contents, this.module.id),
             ]);
 
             this.contents = results[1];

src/addons/mod/resource/components/index/index.ts

@@ -101,9 +101,9 @@ export class AddonModResourceIndexComponent extends CoreCourseModuleMainResource
      */
     protected async fetchContent(refresh?: boolean): Promise<void> {
         // Load module contents if needed. Passing refresh is needed to force reloading contents.
-        await CoreCourse.loadModuleContents(this.module, this.courseId, undefined, false, refresh);
+        const contents = await CoreCourse.getModuleContents(this.module, this.courseId, undefined, false, refresh);
 
-        if (!this.module.contents || !this.module.contents.length) {
+        if (!contents.length) {
             throw new CoreError(Translate.instant('core.filenotfound'));
         }
 
@@ -155,10 +155,10 @@ export class AddonModResourceIndexComponent extends CoreCourseModuleMainResource
                 this.warning = '';
 
                 if (this.isIOS) {
-                    this.shouldOpenInBrowser = CoreFileHelper.shouldOpenInBrowser(this.module.contents[0]);
+                    this.shouldOpenInBrowser = CoreFileHelper.shouldOpenInBrowser(contents[0]);
                 }
 
-                const mimetype = await CoreUtils.getMimeTypeFromUrl(CoreFileHelper.getFileUrl(this.module.contents[0]));
+                const mimetype = await CoreUtils.getMimeTypeFromUrl(CoreFileHelper.getFileUrl(contents[0]));
 
                 this.isStreamedFile = CoreMimetypeUtils.isStreamedMimetype(mimetype);
             }

src/addons/mod/resource/services/resource-helper.ts

@@ -26,7 +26,7 @@ import { CoreDomUtils } from '@services/utils/dom';
 import { CoreMimetypeUtils } from '@services/utils/mimetype';
 import { CoreTextUtils } from '@services/utils/text';
 import { CoreUtilsOpenFileOptions } from '@services/utils/utils';
-import { makeSingleton } from '@singletons';
+import { makeSingleton, Translate } from '@singletons';
 import { AddonModResource, AddonModResourceProvider } from './resource';
 
 /**
@@ -43,15 +43,17 @@ export class AddonModResourceHelperProvider {
      * @return Promise resolved with the HTML.
      */
     async getEmbeddedHtml(module: CoreCourseWSModule, courseId: number): Promise<string> {
+        const contents = await CoreCourse.getModuleContents(module, courseId);
+
         const result = await CoreCourseHelper.downloadModuleWithMainFileIfNeeded(
             module,
             courseId,
             AddonModResourceProvider.COMPONENT,
             module.id,
-            module.contents,
+            contents,
         );
 
-        return CoreMimetypeUtils.getEmbeddedHtml(module.contents[0], result.path);
+        return CoreMimetypeUtils.getEmbeddedHtml(contents[0], result.path);
     }
 
     /**
@@ -61,7 +63,7 @@ export class AddonModResourceHelperProvider {
      * @return Promise resolved with the iframe src.
      */
     async getIframeSrc(module: CoreCourseWSModule): Promise<string> {
-        if (!module.contents.length) {
+        if (!module.contents?.length) {
             throw new CoreError('No contents available in module');
         }
 
@@ -98,15 +100,19 @@ export class AddonModResourceHelperProvider {
     isDisplayedEmbedded(module: CoreCourseWSModule, display: number): boolean {
         const currentSite = CoreSites.getCurrentSite();
 
-        if ((!module.contents.length && !module.contentsinfo) ||
+        if (!CoreFile.isAvailable() ||
-            !CoreFile.isAvailable() ||
+                (currentSite && !currentSite.isVersionGreaterEqualThan('3.7') && this.isNextcloudFile(module))) {
-            (currentSite && !currentSite.isVersionGreaterEqualThan('3.7') && this.isNextcloudFile(module))) {
             return false;
         }
 
-        const ext = module.contentsinfo
+        let ext: string | undefined;
-            ? CoreMimetypeUtils.getExtension(module.contentsinfo.mimetypes[0])
+        if (module.contentsinfo) {
-            : CoreMimetypeUtils.getFileExtension(module.contents[0].filename);
+            ext = CoreMimetypeUtils.getExtension(module.contentsinfo.mimetypes[0]);
+        } else if (module.contents?.length) {
+            ext = CoreMimetypeUtils.getFileExtension(module.contents[0].filename);
+        } else {
+            return false;
+        }
 
         return (display == CoreConstants.RESOURCELIB_DISPLAY_EMBED || display == CoreConstants.RESOURCELIB_DISPLAY_AUTO) &&
             CoreMimetypeUtils.canBeEmbedded(ext);
@@ -144,10 +150,15 @@ export class AddonModResourceHelperProvider {
      * @param siteId Site ID. If not defined, current site.
      * @return Promise resolved with boolean: whether main file is downloadable.
      */
-    isMainFileDownloadable(module: CoreCourseWSModule, siteId?: string): Promise<boolean> {
+    async isMainFileDownloadable(module: CoreCourseWSModule, siteId?: string): Promise<boolean> {
+        const contents = await CoreCourse.getModuleContents(module);
+        if (!contents.length) {
+            throw new CoreError(Translate.instant('core.filenotfound'));
+        }
+
         siteId = siteId || CoreSites.getCurrentSiteId();
 
-        const mainFile = module.contents[0];
+        const mainFile = contents[0];
         const timemodified = CoreFileHelper.getFileTimemodified(mainFile);
 
         return CoreFilepool.isFileDownloadable(siteId, mainFile.fileurl, timemodified);

src/addons/mod/url/components/index/index.ts

@@ -95,11 +95,19 @@ export class AddonModUrlIndexComponent extends CoreCourseModuleMainResourceCompo
                 this.displayDescription = typeof unserialized.printintro == 'undefined' || !!unserialized.printintro;
             }
 
-            // Try to load module contents, it's needed to get the URL with parameters.
+            // Try to get module contents, it's needed to get the URL with parameters.
-            await CoreCourse.loadModuleContents(this.module, this.courseId, undefined, false, refresh, undefined, 'url');
+            const contents = await CoreCourse.getModuleContents(
+                this.module,
+                this.courseId,
+                undefined,
+                false,
+                refresh,
+                undefined,
+                'url',
+            );
 
             // Always use the URL from the module because it already includes the parameters.
-            this.url = this.module.contents[0] && this.module.contents[0].fileurl ? this.module.contents[0].fileurl : undefined;
+            this.url = contents[0] && contents[0].fileurl ? contents[0].fileurl : undefined;
 
             await this.calculateDisplayOptions(url);
 
@@ -112,12 +120,12 @@ export class AddonModUrlIndexComponent extends CoreCourseModuleMainResourceCompo
             this.description = mod.description;
             this.dataRetrieved.emit(mod);
 
-            if (!mod.contents.length) {
+            if (!mod.contents?.length) {
                 // If the data was cached maybe we don't have contents. Reject.
                 throw new CoreError('No contents found in module.');
             }
 
-            this.url = mod.contents && mod.contents[0] && mod.contents[0].fileurl ? mod.contents[0].fileurl : undefined;
+            this.url = mod.contents[0].fileurl ? mod.contents[0].fileurl : undefined;
         }
     }
 

src/addons/mod/url/services/handlers/module.ts

@@ -77,7 +77,8 @@ export class AddonModUrlModuleHandlerService implements CoreCourseModuleHandler
                 // Ignore errors.
             }
 
-            AddonModUrlHelper.open(module.contents[0].fileurl);
+            const contents = await CoreCourse.getModuleContents(module, courseId);
+            AddonModUrlHelper.open(contents[0].fileurl);
         };
 
         const handlerData: CoreCourseModuleHandlerData = {
@@ -141,9 +142,9 @@ export class AddonModUrlModuleHandlerService implements CoreCourseModuleHandler
      */
     protected async hideLinkButton(module: CoreCourseAnyModuleData, courseId: number): Promise<boolean> {
         try {
-            await CoreCourse.loadModuleContents(module, courseId, undefined, false, false, undefined, this.modName);
+            const contents = await CoreCourse.getModuleContents(module, courseId, undefined, false, false, undefined, this.modName);
 
-            return !(module.contents && module.contents[0] && module.contents[0].fileurl);
+            return !(contents[0] && contents[0].fileurl);
         } catch {
             // Module contents could not be loaded, most probably device is offline.
             return true;
@@ -166,11 +167,10 @@ export class AddonModUrlModuleHandlerService implements CoreCourseModuleHandler
      */
     protected async shouldOpenLink(module: CoreCourseModule, courseId: number): Promise<boolean> {
         try {
-            // First of all, make sure module contents are loaded.
+            const contents = await CoreCourse.getModuleContents(module, courseId, undefined, false, false, undefined, this.modName);
-            await CoreCourse.loadModuleContents(module, courseId, undefined, false, false, undefined, this.modName);
 
             // Check if the URL can be handled by the app. If so, always open it directly.
-            const canHandle = await CoreContentLinksHelper.canHandleLink(module.contents[0].fileurl, courseId, undefined, true);
+            const canHandle = await CoreContentLinksHelper.canHandleLink(contents[0].fileurl, courseId, undefined, true);
 
             if (canHandle) {
                 // URL handled by the app, open it directly.

src/core/features/course/classes/main-resource-component.ts

@@ -390,7 +390,7 @@ export class CoreCourseModuleMainResourceComponent implements OnInit, OnDestroy,
             }
         }
 
-        if (!this.module.contents.length || (refresh && !contentsAlreadyLoaded)) {
+        if (!this.module.contents?.length || (refresh && !contentsAlreadyLoaded)) {
             // Try to load the contents.
             const ignoreCache = refresh && CoreApp.isOnline();
 

src/core/features/course/services/course-helper.ts

@@ -730,13 +730,11 @@ export class CoreCourseHelperProvider {
         siteId = siteId || CoreSites.getCurrentSiteId();
 
         if (!files || !files.length) {
-            // Make sure that module contents are loaded.
+            // Try to use module contents.
-            await CoreCourse.loadModuleContents(module, courseId);
+            files = await CoreCourse.getModuleContents(module, courseId);
-
-            files = module.contents;
         }
 
-        if (!files || !files.length) {
+        if (!files.length) {
             throw new CoreError(Translate.instant('core.filenotfound'));
         }
 
@@ -1033,7 +1031,7 @@ export class CoreCourseHelperProvider {
         }
 
         // There's no prefetch handler for the module, just download the files.
-        files = files || module.contents;
+        files = files || module.contents || [];
 
         await CoreFilepool.downloadOrPrefetchFiles(siteId, files, false, false, component, componentId);
     }

src/core/features/course/services/course.ts

@@ -885,9 +885,47 @@ export class CoreCourseProvider {
         }
 
         const mod = await this.getModule(module.id, courseId, sectionId, preferCache, ignoreCache, siteId, modName);
+
+        if (!mod.contents) {
+            throw new CoreError(Translate.instant('core.course.modulenotfound'));
+        }
+
         module.contents = mod.contents;
     }
 
+    /**
+     * Get module contents. If not present, this function will try to load them into module.contents.
+     * It will throw an error if contents cannot be loaded.
+     *
+     * @param module Module to get its contents.
+     * @param courseId The course ID. Recommended to speed up the process and minimize data usage.
+     * @param sectionId The section ID.
+     * @param preferCache True if shouldn't call WS if data is cached, false otherwise.
+     * @param ignoreCache True if it should ignore cached data (it will always fail in offline or server down).
+     * @param siteId Site ID. If not defined, current site.
+     * @param modName If set, the app will retrieve all modules of this type with a single WS call. This reduces the
+     *                number of WS calls, but it isn't recommended for modules that can return a lot of contents.
+     * @return Promise resolved when loaded.
+     */
+    async getModuleContents(
+        module: CoreCourseAnyModuleData,
+        courseId?: number,
+        sectionId?: number,
+        preferCache?: boolean,
+        ignoreCache?: boolean,
+        siteId?: string,
+        modName?: string,
+    ): Promise<CoreCourseModuleContentFile[]> {
+        // Make sure contents are loaded.
+        await this.loadModuleContents(module, courseId, sectionId, preferCache, ignoreCache, siteId, modName);
+
+        if (!module.contents) {
+            throw new CoreError(Translate.instant('core.course.modulenotfound'));
+        }
+
+        return module.contents;
+    }
+
     /**
      * Report a course and section as being viewed.
      *
@@ -1450,7 +1488,7 @@ export type CoreCourseWSModule = {
     noviewlink?: boolean; // Whether the module has no view page.
     completion?: number; // Type of completion tracking: 0 means none, 1 manual, 2 automatic.
     completiondata?: CoreCourseModuleWSCompletionData; // Module completion data.
-    contents: CoreCourseModuleContentFile[];
+    contents?: CoreCourseModuleContentFile[];
     dates?: {
         label: string;
         timestamp: number;
@@ -1589,5 +1627,5 @@ type CoreCompletionUpdateActivityCompletionStatusManuallyWSParams = {
  * Any of the possible module WS data.
  */
 export type CoreCourseAnyModuleData = CoreCourseWSModule | CoreCourseModuleBasicInfo & {
-    contents?: CoreCourseModuleContentFile[]; // Calculated in the app in loadModuleContents.
+    contents?: CoreCourseModuleContentFile[]; // If needed, calculated in the app in loadModuleContents.
 };