ios, android: background refresh

ios/Podfile

@@ -1,5 +1,5 @@
 # Uncomment this line to define a global platform for your project
-# platform :ios, '9.0'
+platform :ios, '10.0'
 
 # CocoaPods analytics sends network stats synchronously affecting flutter build latency.
 ENV['COCOAPODS_DISABLE_STATS'] = 'true'

ios/Podfile.lock

@@ -28,6 +28,8 @@ PODS:
     - Flutter
   - webview_flutter (0.0.1):
     - Flutter
+  - workmanager (0.0.1):
+    - Flutter
 
 DEPENDENCIES:
   - device_info (from `.symlinks/plugins/device_info/ios`)
@@ -43,6 +45,7 @@ DEPENDENCIES:
   - video_player (from `.symlinks/plugins/video_player/ios`)
   - wakelock (from `.symlinks/plugins/wakelock/ios`)
   - webview_flutter (from `.symlinks/plugins/webview_flutter/ios`)
+  - workmanager (from `.symlinks/plugins/workmanager/ios`)
 
 SPEC REPOS:
   trunk:
@@ -75,6 +78,8 @@ EXTERNAL SOURCES:
     :path: ".symlinks/plugins/wakelock/ios"
   webview_flutter:
     :path: ".symlinks/plugins/webview_flutter/ios"
+  workmanager:
+    :path: ".symlinks/plugins/workmanager/ios"
 
 SPEC CHECKSUMS:
   device_info: d7d233b645a32c40dfdc212de5cf646ca482f175
@@ -91,7 +96,8 @@ SPEC CHECKSUMS:
   video_player: 9cc823b1d9da7e8427ee591e8438bfbcde500e6e
   wakelock: b0843b2479edbf6504d8d262c2959446f35373aa
   webview_flutter: 9f491a9b5a66f2573946a389b2677987b0ff8c0b
+  workmanager: 0afdcf5628bbde6924c21af7836fed07b42e30e6
 
-PODFILE CHECKSUM: aafe91acc616949ddb318b77800a7f51bffa2a4c
+PODFILE CHECKSUM: fe0e1ee7f3d1f7d00b11b474b62dd62134535aea
 
 COCOAPODS: 1.10.1

ios/Runner.xcodeproj/project.pbxproj

@@ -339,7 +339,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
 				SUPPORTED_PLATFORMS = iphoneos;
@@ -358,6 +358,7 @@
 				DEVELOPMENT_TEAM = AHDHW7HK24;
 				ENABLE_BITCODE = NO;
 				INFOPLIST_FILE = Runner/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -417,7 +418,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
 				MTL_ENABLE_DEBUG_INFO = YES;
 				ONLY_ACTIVE_ARCH = YES;
 				SDKROOT = iphoneos;
@@ -466,7 +467,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
 				SUPPORTED_PLATFORMS = iphoneos;
@@ -487,6 +488,7 @@
 				DEVELOPMENT_TEAM = AHDHW7HK24;
 				ENABLE_BITCODE = NO;
 				INFOPLIST_FILE = Runner/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -510,6 +512,7 @@
 				DEVELOPMENT_TEAM = AHDHW7HK24;
 				ENABLE_BITCODE = NO;
 				INFOPLIST_FILE = Runner/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -548,4 +551,4 @@
 /* End XCConfigurationList section */
 	};
 	rootObject = 97C146E61CF9000F007C117D /* Project object */;
-}
+}

ios/Runner/AppDelegate.swift

@@ -1,13 +1,27 @@
 import UIKit
 import Flutter
+import workmanager
 
 @UIApplicationMain
 @objc class AppDelegate: FlutterAppDelegate {
-  override func application(
-    _ application: UIApplication,
-    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
-  ) -> Bool {
-    GeneratedPluginRegistrant.register(with: self)
-    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
-  }
+    override func application(
+        _ application: UIApplication,
+        didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
+    ) -> Bool {
+        GeneratedPluginRegistrant.register(with: self)
+        UNUserNotificationCenter.current().delegate = self
+
+        WorkmanagerPlugin.setPluginRegistrantCallback { registry in
+            // registry in this case is the FlutterEngine that is created in Workmanager's performFetchWithCompletionHandler
+            // This will make other plugins available during a background fetch
+            GeneratedPluginRegistrant.register(with: registry)
+        }
+        UIApplication.shared.setMinimumBackgroundFetchInterval(TimeInterval(60 * 15))
+
+        return super.application(application, didFinishLaunchingWithOptions: launchOptions)
+    }
+
+    override func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
+        completionHandler(.alert) // shows banner even if app is in foreground
+    }
 }

ios/Runner/Info.plist

@@ -27,6 +27,10 @@
 	<string>$(FLUTTER_BUILD_NUMBER)</string>
 	<key>LSRequiresIPhoneOS</key>
 	<true/>
+	<key>UIBackgroundModes</key>
+	<array>
+		<string>fetch</string>
+	</array>
 	<key>UILaunchStoryboardName</key>
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>

lib/aggregation.dart

@@ -8,29 +8,15 @@ import 'package:kanbasu/models/brief_info.dart';
 import 'package:kanbasu/utils/courses.dart';
 import 'package:easy_localization/easy_localization.dart';
 import 'package:kanbasu/utils/html.dart';
+import 'package:kanbasu/utils/stream_op.dart';
 import 'package:pedantic/pedantic.dart';
 import 'package:rxdart/rxdart.dart';
 
-Future<List<T>> getListDataFromApi<T>(
-    List<Stream<T>> stream, bool useOnlineData) async {
-  if (useOnlineData) {
-    return await stream.last.toList();
-  } else {
-    return await stream.first.toList();
-  }
-}
-
-Future<T> getItemDataFromApi<T>(
-    List<Future<T>> stream, bool useOnlineData) async {
-  if (useOnlineData) {
-    return (await stream.last);
-  } else {
-    return (await stream.first);
-  }
-}
-
-Stream<BriefInfo> aggregate(CanvasBufferClient api,
-    {bool useOnlineData = false}) async* {
+Stream<BriefInfo> aggregate(
+  CanvasBufferClient api, {
+  bool useOnlineData = false,
+  bool dryRun = false,
+}) async* {
   final latestCourses = toLatestCourses(
       await getListDataFromApi(api.getCourses(), useOnlineData));
   final idToCourse = {
@@ -41,28 +27,40 @@ Stream<BriefInfo> aggregate(CanvasBufferClient api,
   Future<List<BriefInfo>> processCourse(Course course) async {
     final aggregations = <BriefInfo?>[];
 
-    final assignments =
-        await getListDataFromApi(api.getAssignments(course.id), useOnlineData);
-    for (final assignment in assignments) {
-      final newAgg = aggregateFromAssignment(assignment, course);
-      aggregations.add(newAgg);
+    final assignments = await getListDataFromApi(
+      api.getAssignments(course.id),
+      useOnlineData,
+    );
+    if (!dryRun) {
+      for (final assignment in assignments) {
+        final newAgg = aggregateFromAssignment(assignment, course);
+        aggregations.add(newAgg);
 
-      final newAgg2 = aggregateFromAssignmentDue(assignment, course);
-      aggregations.add(newAgg2);
+        final newAgg2 = aggregateFromAssignmentDue(assignment, course);
+        aggregations.add(newAgg2);
+      }
     }
 
-    final submissions =
-        await getListDataFromApi(api.getSubmissions(course.id), useOnlineData);
-    for (final submission in submissions) {
-      final newAgg = aggregateFromSubmission(submission, course);
-      aggregations.add(newAgg);
+    final submissions = await getListDataFromApi(
+      api.getSubmissions(course.id),
+      useOnlineData,
+    );
+    if (!dryRun) {
+      for (final submission in submissions) {
+        final newAgg = aggregateFromSubmission(submission, course);
+        aggregations.add(newAgg);
+      }
     }
 
-    final files =
-        await getListDataFromApi(api.getFiles(course.id), useOnlineData);
-    for (final file in files) {
-      final newAgg = aggregateFromFile(file, course);
-      aggregations.add(newAgg);
+    final files = await getListDataFromApi(
+      api.getFiles(course.id),
+      useOnlineData,
+    );
+    if (!dryRun) {
+      for (final file in files) {
+        final newAgg = aggregateFromFile(file, course);
+        aggregations.add(newAgg);
+      }
     }
 
     return aggregations.whereType<BriefInfo>().toList();
@@ -72,13 +70,18 @@ Stream<BriefInfo> aggregate(CanvasBufferClient api,
   Future<List<BriefInfo>> processAnnouncements() async {
     final aggregations = <BriefInfo?>[];
 
-    final planners = await getListDataFromApi(api.getPlanners(), useOnlineData);
-    for (final planner in planners) {
-      if (planner.plannableType != 'announcement') continue;
-      final course = idToCourse[planner.courseId];
-      if (course != null) {
-        final newAgg = aggregateFromPlanner(planner, course);
-        aggregations.add(newAgg);
+    final planners = await getListDataFromApi(
+      api.getPlanners(),
+      useOnlineData,
+    );
+    if (!dryRun) {
+      for (final planner in planners) {
+        if (planner.plannableType != 'announcement') continue;
+        final course = idToCourse[planner.courseId];
+        if (course != null) {
+          final newAgg = aggregateFromPlanner(planner, course);
+          aggregations.add(newAgg);
+        }
       }
     }
 
@@ -87,17 +90,18 @@ Stream<BriefInfo> aggregate(CanvasBufferClient api,
 
   final subject = PublishSubject<List<BriefInfo>>();
 
-  unawaited(Future.wait(
-    [
+  unawaited(() async {
+    await Future.wait([
       for (final course in latestCourses)
         processCourse(course).then((d) => subject.add(d)),
       processAnnouncements().then((d) => subject.add(d)),
-    ],
-  ).then((_) => subject.close()));
+    ]);
+    await subject.close();
+  }());
 
   final stream = subject.stream.flatMap((value) => Stream.fromIterable(value));
-  await for (final items in stream) {
-    yield items;
+  await for (final item in stream) {
+    yield item;
   }
 }