🆒 Parse json in a seperate isolate with compute

.codecov.yml

@@ -1,2 +1,12 @@
+coverage:
+  precision: 2
+  round: down
+  range: "70...100"
+
+  status:
+    project: no
+    patch: no
+    changes: no
+
 ignore:
   - "**/*.g.dart"

README.md

@@ -4,7 +4,11 @@
 [![codecov](https://codecov.io/gh/toureh/flutter_workshop/branch/master/graph/badge.svg)](https://codecov.io/gh/toureh/flutter_workshop)
 [![Lint](https://img.shields.io/badge/style-pedantic-blue.svg)](https://github.com/dart-lang/pedantic)
 
-This repository contains a sample app that I use to give workshops geared towards beginners to Flutter. I've made an effort to keep the git history clean by doing cohesive commits that each represent a teachable building block in the app.
+This repository contains a sample app that I use to give workshops geared towards beginners to Flutter.
+
+The commit history contains multiple ways of doing the same thing. For example, in one commit we manually spawn an isolate to do work in the background and in a later commit we use use Flutter's handy `compute` function to do the job. In one commit we manually parse and serialize json and in a later commit we do it with code generation.
+
+I've made an effort to squash changes into cohesive commits that each represent a teachable building block in the app.
 
 
 ## Contains examples of:
@@ -14,6 +18,7 @@ This repository contains a sample app that I use to give workshops geared toward
 * Navigation & routing
 * Networking
 * JSON parsing and serialization
+* Moving work to a background isolate
 * BLoC pattern
 * Storing key-value data on disk
 * Dependency injection with InheritedWidget

lib/model/donation/donation_api.dart

@@ -1,38 +1,23 @@
 import 'dart:convert';
-import 'dart:isolate';
 
 import 'package:flutter/foundation.dart';
 import 'package:flutter_workshop/base/base_api.dart';
 import 'package:flutter_workshop/model/donation/donation.dart';
 import 'package:flutter_workshop/model/donation/donation_api_response.dart';
-import 'package:flutter_workshop/util/concurrency.dart';
 import 'package:http/http.dart' as http;
 import 'package:meta/meta.dart';
 
+DonationApiResponse parseDonations(Map<String, dynamic> json) =>
+    DonationApiResponse.fromJson(json);
+
 class DonationApi extends BaseApi {
   DonationApi({@required http.Client client}) : super(client: client);
 
   Future<List<Donation>> getDonations() async {
     final String url = '${baseUrl}listings/categories/33';
     final http.Response response = await get(url);
     final Map<String, dynamic> json = jsonDecode(response.body);
-    final dto =
-        await computeInIsolate<DonationApiResponse>(parseDonations, json);
+    final DonationApiResponse dto = await compute(parseDonations, json);
     return dto.donations;
   }
 }
-
-void parseDonations(SendPort sendPort) async {
-  final port = ReceivePort();
-  sendPort.send(port.sendPort);
-
-  await for (var message in port) {
-    if (message is RespondableMessage) {
-      final json = message.data;
-      final result = DonationApiResponse.fromJson(json);
-      message.sendPort.send(result);
-    }
-
-    port.close();
-  }
-}