aws_appsync 0.1.0

A new Flutter package project.

example/lib/main.dart

import 'dart:async';
import 'dart:convert';

import 'package:aws_appsync/aws_appsync.dart';
import 'package:flutter/material.dart';
import 'package:flutter_json_widget/flutter_json_widget.dart';
import 'package:sembast/sembast_io.dart';
import 'package:super_logging/super_logging.dart';

import 'progress_mixin.dart';

void main() async {
  await SuperLogging.main();
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        fontFamily: 'Courier',
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage>
    with ProgressMixin<MyHomePage> {
  final endpoint = TextEditingController(
    text:
        'https://kdsnweku3zbufknjcyda4arel4.appsync-api.ap-south-1.amazonaws.com/graphql',
  );
  final query = TextEditingController(
    text: r'''
query ListLessons(
  $filter: TableLessonFilterInput
  $limit: Int
  $nextToken: String
) {
  listLessons(filter: $filter, limit: $limit, nextToken: $nextToken) {
    items {
      sourceId
      chapterId
      chapterName
      chapterNumber
      colour
      curriculum
      grade
      lessonName
      lessonNumber
      pages
      pdfLanguage
      s3Key
      slides
      semester
      subject
      subjectSubtypes
      subjectSubtype
      updatedAt
      tags
      metadataOK
      potentialDuplicate
      duplicate
      password
    }
    nextToken
  }
}
''',
  );
  final variables = TextEditingController(text: '{}');
  final accessToken = TextEditingController();

  var results;
  var cacheEnabled = true;
  var priority = CachePriority.network;
  Duration timeTaken;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('AWS AppSync example'),
      ),
      body: SafeArea(
        child: Stack(
          children: <Widget>[
            ListView(
              padding: const EdgeInsets.all(16),
              children: <Widget>[
                TextField(
                  controller: endpoint,
                  decoration: InputDecoration(
                    labelText: 'endpoint',
                  ),
                ),
                TextField(
                  controller: query,
                  decoration: InputDecoration(
                    labelText: 'query',
                  ),
                  maxLines: null,
                ),
                TextField(
                  controller: variables,
                  decoration: InputDecoration(
                    labelText: 'variables',
                  ),
                  maxLines: null,
                ),
                TextField(
                  controller: accessToken,
                  decoration: InputDecoration(
                    labelText: 'accessToken',
                    hintText: 'You can copy this from flutter_cognito_plugin',
                  ),
                ),
                Divider(),
                CheckboxListTile(
                  value: cacheEnabled,
                  onChanged: (value) {
                    setState(() {
                      cacheEnabled = value;
                    });
                  },
                  title: Text('cache enabled'),
                ),
                if (cacheEnabled)
                  DropdownButton(
                    value: priority,
                    onChanged: (value) {
                      setState(() {
                        priority = value;
                      });
                    },
                    items: [
                      DropdownMenuItem(
                        value: CachePriority.network,
                        child: Text('${CachePriority.network}'),
                      ),
                      DropdownMenuItem(
                        value: CachePriority.cache,
                        child: Text('${CachePriority.cache}'),
                      )
                    ],
                  ),
                Divider(),
                Wrap(
                  alignment: WrapAlignment.center,
                  spacing: 16,
                  children: <Widget>[
                    RaisedButton(
                      child: Text('execute'),
                      onPressed: createOnPressed(execute),
                    ),
                    RaisedButton(
                      child: Text('paginate'),
                      onPressed: createOnPressed(paginate),
                    ),
                    RaisedButton(
                      child: Text('delete db'),
                      onPressed: createOnPressed(deleteDB),
                    ),
                  ],
                ),
                Divider(),
                Center(
                    child: Text(
                  'Results',
                  style: Theme.of(context).textTheme.title,
                )),
                if (timeTaken != null) Center(child: Text('(took $timeTaken)')),
                if (results is Map)
                  JsonViewerWidget(results)
                else if (results is List)
                  for (var result in results) JsonViewerWidget(result)
                else
                  Text("$results"),
              ],
            ),
            buildProgressStackWidget(),
          ],
        ),
      ),
    );
  }

  final appSync = AppSync();

  Future<dynamic> execute() async {
    return await appSync.execute(
      endpoint: endpoint.text.trim(),
      query: query.text,
      variables: jsonDecode(variables.text.trim()),
      accessToken: accessToken.text,
      cache: cacheEnabled ? await appSync.getCacheDatabase() : null,
      priority: priority,
    );
  }

  Future<dynamic> paginate() async {
    return appSync.paginate(
      endpoint: endpoint.text.trim(),
      query: query.text,
      variables: jsonDecode(variables.text.trim()),
      accessToken: accessToken.text,
      cache: cacheEnabled ? await appSync.getCacheDatabase() : null,
      priority: priority,
    );
  }

  Future<void> deleteDB() async {
    var db = await appSync.getCacheDatabase();
    await db.close();
    await databaseFactoryIo.deleteDatabase(db.path);
  }

  ProgressMixinTaskWrapper createOnPressed(ProgressMixinTask fn) {
    return wrapTask(() async {
      var s = DateTime.now();
      setState(() {
        timeTaken = null;
      });

      try {
        var data = await fn();
        if (data is Stream) {
          results = [];
          await for (var page in data) {
            if (!mounted) return;
            setState(() {
              results.add(page);
            });
          }
        } else {
          setState(() {
            results = data;
          });
        }
      } catch (e) {
        if (mounted) {
          setState(() {
            results = e;
          });
        }
      }

      setState(() {
        var e = DateTime.now();
        timeTaken = e.difference(s);
      });
    });
  }
}