/li3_aws

Lithium plugin for accessing Amazon Web Services

Primary LanguagePHP

li3_aws

Lithium plugin for accessing Amazon Web Services. Current services to use:

  • Amazon S3

How to install?

Clone the plugin into the libraries folder of your lithium application.

git clone git://github.com/Daikoun/li3_aws.git my_lithium_app/libraries

Enable the plugin in my_lithium_app/app/config/bootstrap/libraries.php.

Libraries::add('li3_aws');

Setup the connection to Amazon S3 in my_lithium_app/app/config/bootstrap/connections.php.

Connections::add('amazon_s3', array(
	'type'    => 'http',
	'adapter' => 'AmazonS3',
	'key'	  => 'my_key',
	'secret'  => 'my_secret',
));

The key and secret you need to copy from your AWS account.

Go to the AWS Management Console -> S3 and create a new bucket.

Create a new Model in lithium and setup the bucket name in the meta array.

<?php

namespace app\models;

class Pictures extends \lithium\data\Model {

	protected $_meta = array(
		'source' => 'myBucketName',
		'connection' => 'amazon_s3',
	);
	
	public $validates = array();
}

?>

And you are ready to go.

Create Buckets:

Use the AWS Management Console (preferred).

Delete Buckets:

Use the AWS Management Console (preferred).

Store files in your bucket:

In your controller, you can do file uploads the same way you do that in MongoDB-GridFs.

	public function add() {
		$picture = Pictures::create();

		if (($this->request->data) && $picture->save($this->request->data)) {
			return $this->redirect(array('Pictures::view', 'args' => array($picture->_id)));
		}
		return compact('picture');
	}

Where the request can contain an uploaded file by using a HTML form.

Store files encrypted in S3.

	public function add() {
		$picture = Pictures::create();

		if (($this->request->data) && $picture->save($this->request->data, array('encryption' => 'AES256'))) {
			return $this->redirect(array('Pictures::view', 'args' => array($picture->_id)));
		}
		return compact('picture');
	}

List files in your bucket:

Currently you can only list the first 1000 files in the bucket. (Will be updated soon) You can use the already generated index function in your lithium controller, e.g.:

	public function index() {
		$pictures = Pictures::all();
		return compact('pictures');
	}

Download files from your bucket:

The structure is similar to use Mongo-GridFs, so that you can easily exchange the storage without changing any source code, just by set the connection in bootstrap. For optimizing downloads from S3, an additional Streamwrapper-Method is implemented.

a) Without StreamWrapper:

Using this method, the file contents are buffered in the PHP memory before you can access them. This can cause memory exceptions, if file size exceeds the PHP memory and also slows down the download process because you have to wait till the whole file is buffered.

	public function view() {
		$picture = Pictures::first($this->request->id);
		$this->_render['auto'] = false;
		$this->response->headers('Content-Type', $picture->headers['Content-Type']);
		$this->response->headers('Content-Length', $picture->headers['Content-Length']);
		$this->response->body = $picture->file;
		return $this->response;
	}

$picture->file contains the file-contents stored as plain text or binary image data.

b) With StreamWrapper:

By using the StreamWrapper you can avoid buffering the file contents. The StreamWrapper helps you to directly pipe the file contents to the output. Another benefit, you can soon provide the download response.

	public function view() {
		$id = $this->request->id;
		$picture = Pictures::first(array('conditions' => array('_id' => $id), 'return' => 'stream'));
		$this->_render['auto'] = false;
		$this->response->headers('Content-Type', $picture->headers['Content-Type']);
		$this->response->headers('Content-Length', $picture->headers['Content-Length']);
		$this->response->body = $picture->file->getBytes();
		return $this->response;
	}

In this case $picture->file is the StreamWrapper-Class li3_aws/data/AmazonS3File.php and provides two functions:

  • getBytes() gives you a string with the whole contents of the file. Actually the contents are also buffered in the PHP memory.
  • getResource() gives you a stream object to control the content stream by hand, e.g.:
	public function view() {
		$id = $this->request->id;
		$picture = Pictures::first(array('conditions' => array('_id' => $id), 'return' => 'stream'));
		$this->_render['auto'] = false;
		header("Content-Type: {$picture->headers['Content-Type']}");
		header("Content-Length: {$picture->headers['Content-Length']}");
		$stream = $picture->file->getResource();
		while (!feof($stream)) {
			echo fgets($stream, 16384);
		} 
		fclose($stream);
		$this->response = null;
		return;
	}

By using getResource() you can minimize buffering and pipe the contents to output soon.

Delete Files from your Bucket:

a) Use Entity:

If you use entity, you need two requests to S3. By using the StreamWrapper you can optimize the first request a little bit.

	public function delete() {
		if (!$this->request->is('post') && !$this->request->is('delete')) {
			$msg = "Pictures::delete can only be called with http:post or http:delete.";
			throw new DispatchException($msg);
		}
		$id = $this->request->id;		
		Pictures::first(array('conditions' => array('_id' => $id), 'return' => 'stream'))->delete();
		return $this->redirect('Pictures::index');
	}

b) Use Model:

The preferred way is to use Model directly to delete the File where only one request is needed.

	public function delete() {
		if (!$this->request->is('post') && !$this->request->is('delete')) {
			$msg = "Pictures::delete can only be called with http:post or http:delete.";
			throw new DispatchException($msg);
		}
		$id = $this->request->id;		
		Pictures::remove(array('_id' => $this->request->id));
		return $this->redirect('Pictures::index');
	}

Using the Model allows you to delete multiple files in one request.

	Pictures::remove(array('_id' => array('foo.jpg', 'bar.jpg'));

Test Cases:

The li3_aws plugin provides you with a mock class simulating an Amazon S3 storage. You can setup your environment, that you access local Mongo-GridFs on development, the AmazonS3-Mock on testing and real Amazon S3 on production. For this use case, you need to move the source setup from the model into the connection. An easy way to achieve this is to create a base model and inherit from that base model.

use \lithium\data\Connections;

class BaseModel extends \lithium\data\Model {

	public static function __init() {
		parent::__init();
		$conn = static::meta('connection');
		$config = Connections::get($conn, array('config' => true));
		if (isset($config['source'])) {
			static::meta('source', $config['source']);
		}
	}
}

Now you can optionally set the source in the connections.

Connections::add('amazon_s3', array(
	'development' => array(
		'type'     => 'MongoDb',
		'host'     => 'localhost',
		'database' => 'picturefs',
		'source'   => 'fs.files',
    ), 
	'test' => array(
		'type'    => 'http',
		'adapter' => 'AmazonS3',
		'key'	  => 'foo',
		'secret'  => 'bar',
		'socket'  => 'li3_aws\tests\mocks\extensions\adapter\data\source\http\MockAmazonSocket'
	),
	'production' => array(
		'type'    => 'http',
		'adapter' => 'AmazonS3',
		'key'	  => 'my_key',
		'secret'  => 'my_secret',
		'source'  => 'myBucketName',
    ),
));

In development environment, you use Mongo-GridFs and in production environment, you use AmazonS3 without changing anything in the source code, because both Stream-Wrapper, MongoGridFSFile and AmazonS3File have the same functions getBytes() and getResource().