Merge pull request #19 from yringler/8-prompt-for-data-usage

8: make service for net permission/ability.

Author: yringler

.vscode/launch.json

@@ -0,0 +1,73 @@
+{
+	// Use IntelliSense to learn about possible attributes.
+	// Hover to view descriptions of existing attributes.
+	// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+	"version": "0.2.0",
+	"configurations": [
+		{
+			"name": "Launch on iOS",
+			"type": "nativescript",
+			"request": "launch",
+			"platform": "ios",
+			"appRoot": "${workspaceRoot}",
+			"sourceMaps": true,
+			"watch": true
+		},
+		{
+			"name": "Test on iOS",
+			"type": "nativescript",
+			"request": "launch",
+			"platform": "ios",
+			"appRoot": "${workspaceRoot}",
+			"sourceMaps": true,
+			"watch": false,
+			"stopOnEntry": true,
+			"launchTests": true,
+			"tnsArgs": [
+				"--justlaunch"
+			]
+		},
+		{
+			"name": "Attach on iOS",
+			"type": "nativescript",
+			"request": "attach",
+			"platform": "ios",
+			"appRoot": "${workspaceRoot}",
+			"sourceMaps": true,
+			"watch": false
+		},
+		{
+			"name": "Launch on Android",
+			"type": "nativescript",
+			"request": "launch",
+			"platform": "android",
+			"appRoot": "${workspaceRoot}",
+			"sourceMaps": true,
+			"watch": true,
+			"tnsArgs": ["--debug-brk", "--bundle"]
+		},
+		{
+			"name": "Test on Android",
+			"type": "nativescript",
+			"request": "launch",
+			"platform": "android",
+			"appRoot": "${workspaceRoot}",
+			"sourceMaps": true,
+			"watch": false,
+			"stopOnEntry": true,
+			"launchTests": true,
+			"tnsArgs": [
+				"--justlaunch"
+			]
+		},
+		{
+			"name": "Attach on Android",
+			"type": "nativescript",
+			"request": "attach",
+			"platform": "android",
+			"appRoot": "${workspaceRoot}",
+			"sourceMaps": true,
+			"watch": false,
+		}
+	]
+}

App_Resources/Android/src/main/AndroidManifest.xml

@@ -13,6 +13,7 @@
 	<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
 	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
 	<uses-permission android:name="android.permission.INTERNET"/>
+	<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
 
 	<application
 		android:name="com.tns.NativeScriptApplication"

src/app/home/home.component.html

@@ -1,9 +1,14 @@
 <ActionBar class="action-bar">
-    <Label class="action-bar-title" text="Home"></Label>
+	<ActionItem ios.systemicon="2" android.systemicon="ic_menu_preferences" (tap)="updatePermissionSetting()"></ActionItem>
 </ActionBar>
 
 <StackLayout class="page">
     <daily-lesson
     [track]="track"
-    *ngFor="let track of todaysLessons$ | async"></daily-lesson>
+	*ngFor="let track of todaysLessons$ | async"></daily-lesson>
+	<Progress
+	*ngIf="currentProgress > 0 && currentProgress < 100"
+	[value]="currentProgress"
+	maxvalue="100"
+	></Progress>
 </StackLayout>

src/app/home/home.component.ts

@@ -1,25 +1,51 @@
-import { Component, OnInit } from "@angular/core";
+import { Component, OnInit, NgZone } from "@angular/core";
 import { DailyLessonTrack } from "../shared/models/dailyLessons";
 import { Observable } from "rxjs";
 import { DailyLessonService } from "../shared/services/daily-lesson.service";
-import { map, tap } from "rxjs/operators";
+import { map } from "rxjs/operators";
+import { RequestNetworkPermissionService } from "../shared/services/request-network-permission.service";
+import { NetworkPermissionService } from "../shared/services/network-permission.service";
+import { DownloadProgressService, DownloadProgress } from "../shared/services/download-progress.service";
 
 @Component({
-    selector: "Home",
-    moduleId: module.id,
-    templateUrl: "./home.component.html"
+	selector: "Home",
+	moduleId: module.id,
+	templateUrl: "./home.component.html"
 })
 export class HomeComponent implements OnInit {
 
-    todaysLessons$: Observable<DailyLessonTrack[]>;
+	todaysLessons$: Observable<DailyLessonTrack[]>;
 
-    constructor(private lessonService: DailyLessonService) { }
+	/** @description How far along an ongoing download is. */
+	currentProgress: number;
+
+	constructor(
+		private lessonService: DailyLessonService,
+		private networkPermission: NetworkPermissionService,
+		private requestPermission: RequestNetworkPermissionService,
+		private downloadProgress: DownloadProgressService,
+		private zone: NgZone
+	) { }
 
 	ngOnInit(): void {
 		this.todaysLessons$ = this.lessonService.getLibrary().pipe(
 			map(library => {
-                return library.query({ date: 0 })
-            })
-        );
-    }
+				return library.query({ date: 0 })
+			})
+		);
+
+		// If our app ever wants to download something but can't because we don't know if user
+		// allows mobile data downloads, ask.
+		this.networkPermission.getPermissionRequestCheck().subscribe(
+			() => this.requestPermission.requestPermission()
+		)
+
+		this.downloadProgress.getProgress().subscribe(progress => {
+			this.zone.run(() => this.currentProgress = progress.progress);
+		})
+	}
+
+	updatePermissionSetting() {
+		this.requestPermission.requestPermission();
+	}
 }

src/app/shared/services/download-progress.service.spec.ts

@@ -0,0 +1,12 @@
+import { TestBed } from '@angular/core/testing';
+
+import { DownloadProgressService } from './download-progress.service';
+
+describe('DownloadProgressService', () => {
+  beforeEach(() => TestBed.configureTestingModule({}));
+
+  it('should be created', () => {
+    const service: DownloadProgressService = TestBed.get(DownloadProgressService);
+    expect(service).toBeTruthy();
+  });
+});

src/app/shared/services/download-progress.service.ts

@@ -0,0 +1,25 @@
+import { Injectable } from '@angular/core';
+import { Subject, Subscribable } from 'rxjs';
+import { distinct, debounceTime } from 'rxjs/operators';
+
+export class DownloadProgress {
+	url: string;
+	progress: number;
+}
+
+@Injectable({
+	providedIn: 'root'
+})
+export class DownloadProgressService {
+	private progress$: Subject<DownloadProgress> = new Subject;
+
+	constructor() { }
+
+	getProgress(): Subscribable<DownloadProgress> {
+		return this.progress$.asObservable();
+	}
+
+	setProgress(progress: DownloadProgress) {
+		this.progress$.next(progress);
+	}
+}

src/app/shared/services/lesson-media.service.ts

@@ -1,11 +1,13 @@
 import { Injectable } from '@angular/core';
 import { Lesson, LessonQuery } from '../models/dailyLessons';
-import { Observable, from, ReplaySubject, of, Subject, timer, throwError, defer } from 'rxjs';
-import { map, catchError, tap, mergeMap, concatMap, retryWhen, take, delay, retry } from 'rxjs/operators';
-import { path, knownFolders, File } from 'tns-core-modules/file-system/file-system';
+import { Observable,  ReplaySubject, of, Subject, throwError, defer, concat } from 'rxjs';
+import { map, catchError, tap, mergeMap, concatMap, retry, switchMap, skipWhile, first } from 'rxjs/operators';
+import { path, knownFolders, File, } from 'tns-core-modules/file-system/file-system';
 import { DownloadProgress } from "nativescript-download-progress"
 import { DailyLessonService } from './daily-lesson.service';
 import { MediaManifestService } from './media-manifest.service';
+import { NetworkPermissionService, PermissionReason } from './network-permission.service';
+import { DownloadProgressService } from './download-progress.service';
 
 /**
  * @description The folder where media is downloaded to.
@@ -21,17 +23,17 @@ export class LessonMediaService {
 
 	constructor(
 		private dailyLessonService: DailyLessonService,
-		private mediaManifestService: MediaManifestService
+		private mediaManifestService: MediaManifestService,
+		private networkPermissionService: NetworkPermissionService,
+		private downloadProgress: DownloadProgressService
 	) {
 		// #11, #12: The current downloader seems to have issues with concurrent downloads.
 		// so wait until all pending downloads are completed before doing the next one.
 		this.loadRequest$.pipe(
 			concatMap(([lesson, subject]) => {
-				this.loadMedia(lesson).subscribe(
-					path => subject.next(path)
+				return this.loadMedia(lesson).pipe(
+					tap(path => path && subject.next(path))
 				);
-
-				return of(null);
 			})
 		).subscribe();
 	}
@@ -78,22 +80,59 @@ export class LessonMediaService {
 				if (downloadItem != null) {
 					return of(downloadItem.path);
 				} else {
-					return this.downloadLesson(lesson);
+					return this.downloadLessonWithPermission(lesson);
 				}
 			})
 		);
 	}
 
+	/** @description Waits for permission, then downloads the lesson. */
+	private downloadLessonWithPermission(lesson: Lesson): Observable<string> {
+		return this.networkPermissionService.getPermission().pipe(
+			// Ask for permission from user, if that's the only reason can't download.
+			tap(permission => {
+				if (!permission.canDownload && permission.reason == PermissionReason.unknown) {
+					this.networkPermissionService.requestPermission();
+				}
+			}),
+			// Don't do anything until can download.
+			skipWhile(permission => !permission.canDownload),
+			first(),
+			switchMap(() => this.downloadLesson(lesson))
+		);
+	}
+
+	/** @description Downloads the lesson. */
 	private downloadLesson(lesson: Lesson): Observable<string> {
-		const filePath = path.join(downloadFolder, `${lesson.id}.mp3`);
-		
-		return defer(() => new DownloadProgress().downloadFile(lesson.source, filePath)).pipe(
-			tap(() => console.log(`Attempting download: ${filePath} from ${lesson.source}`)),
+		const filePath = path.join(downloadFolder, `${lesson.id}`);
+
+		return defer(() => {
+			console.log(`Attempting download: ${lesson.source}`);
+
+			let downloader = new DownloadProgress();
+			downloader.addProgressCallback(progress => {
+				this.downloadProgress.setProgress({
+					progress: progress * 100,
+					url: lesson.source
+				});
+			});
+
+			return downloader.downloadFile(lesson.source, filePath);
+		}).pipe(
 			// Known bug: sometimes download fails.
 			catchError(err => {
 				// I observed that err is -always- usually an empty object.
 				console.log(`Download error (from ${lesson.source}): ${JSON.stringify(err)}`);
-				return throwError(err);
+
+				if (File.exists(filePath)) {
+					return concat(
+						// If there's a partial, invalid file, delete it.
+						File.fromPath(filePath).remove(),
+						throwError(err)
+					)
+				} else {
+					return throwError(err);
+				}
 			}),
 			retry(3),
 			tap(file => console.log(`downloaded to: ${file && file.path}`)),

src/app/shared/services/network-permission.service.spec.ts

@@ -0,0 +1,12 @@
+import { TestBed } from '@angular/core/testing';
+
+import { NetworkPermissionService } from './network-permission.service';
+
+describe('NetworkPermissionService', () => {
+  beforeEach(() => TestBed.configureTestingModule({}));
+
+  it('should be created', () => {
+    const service: NetworkPermissionService = TestBed.get(NetworkPermissionService);
+    expect(service).toBeTruthy();
+  });
+});