Doctrine Key Value Stores

The Persistence interfaces are rather overkill for many implementations in the NoSQL world that are only key-value stores with some additional features on top. Doctrine Key Value Store to the rescue. This project offers a much simpler lightweight API that is centered on a key-value API to fetch/save objects.

Single- or multi-value primary keys
Unstructured/schema-less values that are mapped onto objects
Depending on the implementation embedded values/objects are supported
No complex mapping necessary, just put @Entity on the class and all properties are automatically mapped unless @Transient is given. At least one property has to be @Id. Depends on the underlying vendor though.
Properties dont have to exist on the class, public properties are created for missing ones.
No support for references to other objects
EventListener for ODM/ORM that allows to manage key-value entities and collections of them as properties (postLoad, postUpdate, postPersist, postRemove)
Stripped down Object Manager Interface
Data-mapper as any other Doctrine library and persistence and data-objects are separated.
Inheritance (Single- or Multiple-Storage)

Implementations

Following vendors are targeted:

Microsoft Azure Table (Implemented)
Doctrine\Common\Cache provider (Implemented)
RDBMS (Implemented)
Couchbase (Implemented)
Amazon DynamoDB (Implemented)
CouchDB (Implemented)
Cassandra
MongoDB (Implemented)
Riak (Implemented)
Redis (Implemented)

We happily accept contributions for any of the drivers.

Example

Suppose we track e-mail campaigns based on campaign id and recipients.

<?php
use Doctrine\KeyValueStore\Mapping\Annotations as KeyValue;

/**
 * @KeyValue\Entity(storageName="responses")
 */
class Response
{
    const RECEIVE = 0;
    const OPEN = 10;
    const CLICK = 20;
    const ACTION = 30;

    /** @KeyValue\Id */
    private $campaign;
    /** @KeyValue\Id */
    private $recipient;
    private $status;
    private $date;

    public function __construct($campaign, $recipient, $status)
    {
        $this->campaign = $campaign;
        $this->recipient = $recipient;
        $this->status = $status;
    }
}

Create

<?php
$response = new Response("1234", "kontakt@beberlei.de", Response::RECEIVE);

$entityManager->persist($response);
//.... persists as much as you can :-)

$entityManager->flush();

Read

<?php
$response = $entityManager->find("Response",array("campaign" => "1234","recipient" => "kontakt@beberlei.de"));

Update

same as create, just reuse the same id.

Delete

<?php
$response = $entityManager->find("Response",array("1234","kontakt@beberlei.de"));
$entityManager->remove($response);
$entityManager->flush();

Configuration

There is no factory yet that simplifies the creation process, here is the full code necessary to instantiate a KeyValue EntityManager with a Doctrine Cache backend:

<?php
use Doctrine\KeyValueStore\EntityManager;
use Doctrine\KeyValueStore\Configuration;
use Doctrine\KeyValueStore\Mapping\AnnotationDriver;
use Doctrine\KeyValueStore\Storage\DoctrineCacheStorage;
use Doctrine\Common\Cache\ArrayCache;
use Doctrine\Common\Annotations\AnnotationReader;

$cache = new ArrayCache;
$storage = new DoctrineCacheStorage($cache);

$reader = new AnnotationReader();
$metadata = new AnnotationDriver($reader);
$config = new Configuration();
$config->setMappingDriverImpl($metadata);
$config->setMetadataCache($cache);

$entityManager = new EntityManager($storage, $config);

If you want to use WindowsAzure Table you can use the following configuration to instantiate the storage:

use Doctrine\KeyValueStore\Storage\AzureSdkTableStorage;
use WindowsAzure\Common\ServicesBuilder;

$connectionString = ""; // Windows Azure Connection string
$builder = ServicesBuilder::getInstance();
$client = $builder->createTableService($connectionString);

$storage = new AzureSdkTableStorage($client);

If you want to use Doctrine DBAL as backend:

$params = array();
$tableName = "storage";
$idColumnName = "id";
$dataColumnName = "serialized_data";

$conn = DriverManager::getConnection($params);
$storage = new DBALStorage($conn, $tableName, $idColumnName, $dataColumnName);

doctrine/KeyValueStore