line_bot 0.0.2

Library of the LINE Messaging API for Dart. The Library follows the LINE official Messaging API document and helps you to build your Bot much simpler and easier.

example/main.dart

import 'dart:convert';
import 'dart:io';

import 'package:line_bot/line_bot.dart';

Future main() async {
  var envVars = Platform.environment;
  var lineChannelSecret = envVars['LINE_CHANNEL_SECRET'];
  var lineChannelAccessToken = envVars['LINE_CHANNEL_ACCESS_TOKEN'];
  var lineBotApi = LineBotApi(lineChannelAccessToken);
  var webhookParser = WebhookParser(lineChannelSecret);
  var server = await HttpServer.bind(
    InternetAddress.loopbackIPv4,
    8080,
  );
  await for (var request in server) {
    if (request.method == 'POST' && request.uri.path == '/callback') {
      handleRequest(request, webhookParser, lineBotApi);
    } else {
      handleUnSupportedRequest(request);
    }
  }
}

void handleRequest(HttpRequest request, WebhookParser webhookParser,
    LineBotApi lineBotApi) async {
  WebhookEvent message;
  var response = request.response;
  var content = await utf8.decoder.bind(request).join();
  try {
    message = webhookParser.parser(
        content.toString(), request.headers['x-line-signature'][0]);
  } on InvalidSignatureError {
    await response
      ..statusCode = HttpStatus.badRequest
      ..write('InvalidSignatureError')
      ..close();
    return;
  }
  if (message.events.isNotEmpty) {
    var messages = [
      Message(type: 'text', text: message.events[0].message.text)
    ];
    await lineBotApi.replyMessage(message.events[0].replyToken, messages);
  }
  response
    ..statusCode = HttpStatus.ok
    ..write('Request Accepted.')
    ..close();
}

void handleUnSupportedRequest(HttpRequest request) {
  var response = request.response;
  response
    ..statusCode = HttpStatus.methodNotAllowed
    ..write('Unsupported request: ${request.method}.')
    ..close();
}