MOBILE-3245 grades: Fix course data population in grades

src/core/course/providers/helper.ts

@@ -919,7 +919,7 @@ export class CoreCourseHelperProvider {
             const totalOffline = offlineCompletions.length;
             let loaded = 0;
 
-            offlineCompletions = this.utils.arrayToObject(offlineCompletions, 'cmid');
+            const offlineCompletionsMap = this.utils.arrayToObject(offlineCompletions, 'cmid');
 
             // Load the offline data in the modules.
             for (let i = 0; i < sections.length; i++) {
@@ -931,7 +931,7 @@ export class CoreCourseHelperProvider {
 
                 for (let j = 0; j < section.modules.length; j++) {
                     const module = section.modules[j],
-                        offlineCompletion = offlineCompletions[module.id];
+                        offlineCompletion = offlineCompletionsMap[module.id];
 
                     if (offlineCompletion && typeof module.completiondata != 'undefined' &&
                             offlineCompletion.timecompleted >= module.completiondata.timecompleted * 1000) {

src/core/courses/providers/courses.ts

@@ -15,7 +15,7 @@
 import { Injectable } from '@angular/core';
 import { CoreEventsProvider } from '@providers/events';
 import { CoreLoggerProvider } from '@providers/logger';
-import { CoreSitesProvider } from '@providers/sites';
+import { CoreSitesProvider, ReadingStrategy } from '@providers/sites';
 import { CoreSite } from '@classes/site';
 
 /**
@@ -774,18 +774,21 @@ export class CoreCoursesProvider {
      * @param siteId Site to get the courses from. If not defined, use current site.
      * @return Promise resolved with the courses.
      */
-    getUserCourses(preferCache?: boolean, siteId?: string): Promise<any[]> {
+    getUserCourses(preferCache?: boolean, siteId?: string, strategy?: ReadingStrategy): Promise<any[]> {
         return this.sitesProvider.getSite(siteId).then((site) => {
 
             const userId = site.getUserId(),
                 data: any = {
                     userid: userId
                 },
+                strategyPreSets = strategy
+                    ? this.sitesProvider.getReadingStrategyPreSets(strategy)
+                    : { omitExpires: !!preferCache },
                 preSets = {
                     cacheKey: this.getUserCoursesCacheKey(),
                     getCacheUsingCacheKey: true,
-                    omitExpires: !!preferCache,
-                    updateFrequency: CoreSite.FREQUENCY_RARELY
+                    updateFrequency: CoreSite.FREQUENCY_RARELY,
+                    ...strategyPreSets,
                 };
 
             if (site.isVersionGreaterEqualThan('3.7')) {

src/core/courses/providers/helper.ts

@@ -107,7 +107,7 @@ export class CoreCoursesHelperProvider {
             return Promise.resolve();
         }
 
-        let coursesInfo = [],
+        let coursesInfo = {},
             courseInfoAvailable = false;
 
         const site = this.sitesProvider.getCurrentSite(),

src/core/grades/providers/helper.ts

@@ -15,7 +15,7 @@
 import { Injectable } from '@angular/core';
 import { NavController } from 'ionic-angular';
 import { CoreLoggerProvider } from '@providers/logger';
-import { CoreSitesProvider } from '@providers/sites';
+import { CoreSitesProvider, ReadingStrategy } from '@providers/sites';
 import { CoreCoursesProvider } from '@core/courses/providers/courses';
 import { CoreCourseProvider } from '@core/course/providers/course';
 import { CoreGradesProvider } from './grades';
@@ -198,22 +198,50 @@ export class CoreGradesHelperProvider {
      * @param grades Grades to get the data for.
      * @return Promise always resolved. Resolve param is the formatted grades.
      */
-    getGradesCourseData(grades: any): Promise<any> {
-        // Using cache for performance reasons.
-        return this.coursesProvider.getUserCourses(true).then((courses) => {
-            const indexedCourses = {};
-            courses.forEach((course) => {
-                indexedCourses[course.id] = course;
-            });
+    async getGradesCourseData(grades: any[]): Promise<any> {
+        // Obtain courses from cache to prevent network requests.
+        const courses = await this.coursesProvider.getUserCourses(undefined, undefined, ReadingStrategy.OnlyCache);
 
-            grades.forEach((grade) => {
-                if (typeof indexedCourses[grade.courseid] != 'undefined') {
-                    grade.courseFullName = indexedCourses[grade.courseid].fullname;
+        const coursesMap = this.utils.arrayToObject(courses, 'id');
+        const coursesWereMissing = this.addCourseData(grades, coursesMap);
+
+        // If any course wasn't found, make a network request.
+        if (coursesWereMissing) {
+            const coursesPromise = this.coursesProvider.isGetCoursesByFieldAvailable()
+                ? this.coursesProvider.getCoursesByField('ids', grades.map((grade) => grade.courseid))
+                : this.coursesProvider.getUserCourses(undefined, undefined, ReadingStrategy.PreferNetwork);
+
+            const courses = await coursesPromise;
+
+            const coursesMap = this.utils.arrayToObject(courses, 'id');
+
+            this.addCourseData(grades, coursesMap);
         }
-            });
 
-            return grades;
-        });
+        return grades.filter((grade) => grade.courseFullName !== undefined);
+    }
+
+    /**
+     * Adds course data to grades.
+     *
+     * @param grades Array of grades to populate.
+     * @param courses HashMap of courses to read data from.
+     * @return Boolean indicating if some courses were not found.
+     */
+    protected addCourseData(grades: any[], courses: any): boolean {
+        let someCoursesAreMissing = false;
+
+        for (const grade of grades) {
+            if (!(grade.courseid in courses)) {
+                someCoursesAreMissing = true;
+
+                continue;
+            }
+
+            grade.courseFullName = courses[grade.courseid].fullname;
+        }
+
+        return someCoursesAreMissing;
     }
 
     /**

src/providers/sites.ts

@@ -26,7 +26,7 @@ import { CoreUtilsProvider } from './utils/utils';
 import { CoreWSProvider } from './ws';
 import { CoreConstants } from '@core/constants';
 import { CoreConfigConstants } from '../configconstants';
-import { CoreSite } from '@classes/site';
+import { CoreSite, CoreSiteWSPreSets } from '@classes/site';
 import { SQLiteDB, SQLiteDBTableSchema } from '@classes/sqlitedb';
 import { Md5 } from 'ts-md5/dist/md5';
 import { WP_PROVIDER } from '@app/app.module';
@@ -158,6 +158,12 @@ export interface CoreSiteSchema {
     migrate?(db: SQLiteDB, oldVersion: number, siteId: string): Promise<any> | void;
 }
 
+export const enum ReadingStrategy {
+    OnlyCache,
+    PreferCache,
+    PreferNetwork,
+}
+
 /*
  * Service to manage and interact with sites.
  * It allows creating tables in the databases of all sites. Each service or component should be responsible of creating
@@ -1730,4 +1736,28 @@ export class CoreSitesProvider {
 
         return reset;
     }
+
+    /**
+     * Returns presets for a given reading strategy.
+     *
+     * @param strategy Reading strategy.
+     * @return PreSets options object.
+     */
+    getReadingStrategyPreSets(strategy: ReadingStrategy): CoreSiteWSPreSets {
+        switch (strategy) {
+            case ReadingStrategy.PreferCache:
+                return {
+                    omitExpires: true,
+                };
+            case ReadingStrategy.OnlyCache:
+                return {
+                    omitExpires: true,
+                    forceOffline: true,
+                };
+            case ReadingStrategy.PreferNetwork:
+            default:
+                return {};
+        }
+    }
+
 }