store.md

Store

In the end, the events have to be saved somewhere. The library is based on doctrine dbal and offers two different store strategies.

But it is also possible to develop your own store by implementing the Store interface.

Create DBAL connection

The first thing we need for our store is a DBAL connection:

use Doctrine\DBAL\DriverManager;

$connection = DriverManager::getConnection([
    'url' => 'mysql://user:secret@localhost/app'
]);

📖 You can find out more about how to create a connection here

Store types

We offer two store strategies that you can choose as you like.

Single Table Store

With the SingleTableStore everything is saved in one table. The dbal connection is needed, a mapping of the aggregate class and aggregate name and, last but not least, the table name.

use Patchlevel\EventSourcing\Store\SingleTableStore;

$store = new SingleTableStore(
    $connection,
    [
        Profile::class => 'profile'
    ],
    'eventstore'
);

📖 You can switch between strategies using the pipeline.

Multi Table Store

With the MultiTableStore a separate table is created for each aggregate type. In addition, a meta table is created by referencing all events in the correct order. The dbal connection is needed, a mapping of the aggregate class and table name and, last but not least, the table name for the metadata.

use Patchlevel\EventSourcing\Store\MultiTableStore;

$store = new MultiTableStore(
    $connection,
    [
        Profile::class => 'profile'
    ],
    'eventstore'
);

📖 You can switch between strategies using the pipeline.

Schema Manager

With the help of the SchemaManager, the database structure can be created, updated and deleted.

Create schema

use Patchlevel\EventSourcing\Schema\DoctrineSchemaManager;

(new SchemaManager())->create($store);

Update schema

use Patchlevel\EventSourcing\Schema\DoctrineSchemaManager;

(new SchemaManager())->update($store);

Drop schema

use Patchlevel\EventSourcing\Schema\DoctrineSchemaManager;

(new SchemaManager())->drop($store);

Migration

You can also manage your schema with doctrine migrations.

In order to be able to use doctrine/migrations, you have to install the associated package.

composer require doctrine/migrations

We have added a schema provider for doctrine migrations so that you just have to plug the whole thing together.

use Patchlevel\EventSourcing\Schema\MigrationSchemaProvider;

$schemaProvider = new MigrationSchemaProvider($store);

You can plug this together, for example, as follows to create CLI applications like cli.php:

use Doctrine\DBAL\DriverManager;
use Doctrine\Migrations\DependencyFactory;
use Doctrine\Migrations\Configuration\Migration\PhpFile;
use Doctrine\Migrations\Configuration\Connection\ExistingConnection;
use Doctrine\Migrations\Tools\Console\Command;
use Symfony\Component\Console\Application;

$connection = DriverManager::getConnection([
    'url' => 'mysql://user:secret@localhost/app'
]);

$config = new PhpFile('migrations.php');

$dependencyFactory = DependencyFactory::fromConnection(
    $config, 
    new ExistingConnection($connection)
);

$store = /* define your doctrine store */;

$dependencyFactory->setService(
    SchemaProvider::class, 
    new MigrationSchemaProvider($store)
);

$cli = new Application('Doctrine Migrations');
$cli->setCatchExceptions(true);

$cli->addCommands(array(
    new Command\ExecuteCommand($dependencyFactory),
    new Command\GenerateCommand($dependencyFactory),
    new Command\LatestCommand($dependencyFactory),
    new Command\ListCommand($dependencyFactory),
    new Command\MigrateCommand($dependencyFactory),
    new Command\DiffCommand($dependencyFactory),
    new Command\StatusCommand($dependencyFactory),
    new Command\VersionCommand($dependencyFactory),
));

$cli->run();

📖 Here you can find more information on how to configure doctrine migration.

Now you can execute commands like:

cli.php migrations:diff
cli.php migrations:migrate