typetalk api use php (guzzle)

typetalk.php

<?php

/**
 * 前準備
 * 1.Composer をインストールする(https://getcomposer.org/doc/00-intro.md)
 * 2.Guzzle をインストール
  {
    "require": {
      "guzzle/guzzle": "dev-master"
    }
  }
 */
require_once './vendor/autoload.php';

use Guzzle\Http\Client;

$clientId = 'xxxxxxxxxxxxxxxxxxxx';
$clientSecret = 'xxxxxxxxxxxxxxxxxxxx';
$topicId = 'xxx';

$msg = 'Hello, Typetalk!';

$client = new Client;

$res = $client->post('https://typetalk.in/oauth2/access_token', null, [
        'client_id' => $clientId,
        'client_secret' => $clientSecret,
        'grant_type' => 'client_credentials',
        'scope' => 'topic.post',
    ])->send();

$accessToken = json_decode($res->getBody('true'), true)['access_token'];

$client->post(
    "https://typetalk.in/api/v1/topics/{$topicId}", ['Authorization' => 'Bearer ' . $accessToken], ['message' => $msg]
)->send();