It is necessary to make access right to s3 bucket beforehand with IAM.
Use php library to upload to s3. Here is code.
require 'vendor/autoload.php';
if(file_exists($_FILES['upfile']['tmp_name'])){
	$ext = substr($_FILES['upfile']['name'], strrpos($_FILES['upfile']['name'],'.') + 1);
	echo $ext."<br>";
	if(strtolower($ext) !== 'png' && strtolower($ext) !== 'jpg' && strtolower($ext) !== 'jpeg' && strtolower($ext) !== 'gif'){
		echo '画像以外のファイルが指定されています。画像ファイル(png/jpg/jpeg/gif)を指定して下さい';
		exit();
	}
	$tmpname = str_replace('/tmp/', '', $_FILES['upfile']['tmp_name']);
	echo $tmpname;
	$s3client = new Aws\S3\S3Client([
			'credentials' => [
					'key' => '',
					'secret' => ''
			],
			'region' => 'ap-northeast-1',
			'version' => 'latest',
	]);
	$result = $s3client->putObject([
			'Bucket' => 'zeus-image',
			'Key' => 'test.png',
			'SourceFile' => $_FILES['upfile']['tmp_name'],
			'Content-Type' => mime_content_type($_FILES['upfile']['tmp_name']),
	]);
}
?>
<div id="content">
<h2>画像管理</h2>
<hr>
<form action="#" method="POST" enctype="multipart/form-data">
<div id="drag-drop-area">
 <div class="drag-drop-inside">
  <p class="drag-drop-info">ここにファイルをアップロード</p>
  <p>または</p>
  <!-- <input type="file" value="ファイルを選択" name="image"> -->
  <p class="drag-drop-buttons"><input id="fileInput" type="file" value="ファイルを選択" name="upfile"></p>
      <input type="submit" value="送信">
   </div>
  </div>
</form>
HTML form view

s3

You can confirm that it is being uploaded properly.
 
					 
