Set up Amplify REST API

amplify add api

? Please select from one of the below mentioned services: 
    `REST`
? Provide a friendly name for your resource to be used as a label for this category in the project: 
    `api`
? Provide a path (e.g., /book/{isbn}): 
    `/todo`
? Choose a Lambda source 
    `Create a new Lambda function`
? Provide a friendly name for your resource to be used as a label for this category in the project: 
    `todo`
? Provide the AWS Lambda function name: 
    `todo`
? Choose the function runtime that you want to use: 
    `NodeJS`
? Choose the function template that you want to use: 
    `Serverless ExpressJS function (Integration with API Gateway)`
? Do you want to access other resources created in this project from your Lambda function? 
    `No`
? Do you want to invoke this function on a recurring schedule? 
    `No`
? Do you want to edit the local lambda function now?
    `No`
? Restrict API access 
    `No`
? Do you want to add another path? 
    `No`

amplify push

dependencies:
  flutter:
    sdk: flutter
  amplify_flutter: ^1.0.0
  amplify_api: ^1.0.0
  amplify_auth_cognito: ^1.0.0

import 'package:amplify_flutter/amplify_flutter.dart';
import 'package:amplify_api/amplify_api.dart';
import 'package:amplify_auth_cognito/amplify_auth_cognito.dart';
import 'package:flutter/material.dart';

import 'amplifyconfiguration.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  @override
  void initState() {
    super.initState();
    _configureAmplify();
  }

  Future<void> _configureAmplify() async {
    // Add the following line to add API plugin to your app.
    // Auth plugin needed for IAM authorization mode, which is default for REST API.
    final auth = AmplifyAuthCognito();
    final api = AmplifyAPI();
    await Amplify.addPlugins([api, auth]);

    try {
      await Amplify.configure(amplifyconfig);
    } on AmplifyAlreadyConfiguredException {
      safePrint(
          'Tried to reconfigure Amplify; this can occur when your app restarts on Android.');
    }
  }

  Future<void> onTestApi() async {
    // Edit this function with next steps.
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Padding(
          padding: const EdgeInsets.all(20.0),
          child: ElevatedButton(
            onPressed: onTestApi,
            child: const Text('Rest API'),
          ),
        ),
      ),
    );
  }
}

Future<void> postTodo() async {
  try {
    final restOperation = Amplify.API.post(
      'todo',
      body: HttpPayload.json({'name': 'Mow the lawn'}),
    );
    final response = await restOperation.response;
    print('POST call succeeded');
    print(response.decodeBody());
  } on ApiException catch (e) {
    print('POST call failed: $e');
  }
}