# Package and bundle structure and namespaces

All code contributions to Ibexa DXP must follow package and bundle structure and namespace standards.

If you wish to contribute to Ibexa DXP development, you need to adhere to the package and bundle structure and namespace standards.

The following conventions apply to contributions to Ibexa core code, not to third party packages.

> **Note: Note**
>
> New code needs to follow the rules outlined here. They're being applied progressively to existing code.

## Root PHP namespace

Define Ibexa DXP core PHP code in a namespace with the following prefix:

```php
namespace Ibexa;
```

A package which groups some DXP features can use an additional prefix, for example:

```php
namespace Ibexa\Commerce;
```

```php
namespace Ibexa\Personalization;
```

## Packages

The general package directory structure and corresponding PHP namespace mapping are:

```text
.
+-- src
|   +-- bundle (`Ibexa\Bundle\<PackageName>`)
|   +-- contracts (`Ibexa\Contracts\<PackageName>`)
|   +-- lib (`Ibexa\<PackageName>`)
+-- tests
|   +-- bundle (`Ibexa\Tests\Bundle\<PackageName>`)
|   +-- integration (`Ibexa\Tests\Integration\<PackageName>`)
|   +-- lib (`Ibexa\Tests\<PackageName>`)
```

If a package doesn't contain some of the described parts, you can skip those directories.

### Implementation (lib)

The `src/lib` directory and its corresponding `Ibexa\<PackageName>` namespace are meant for internal implementation not tied to the Symfony Framework.

Examples:

```php
namespace Ibexa\Search;
```

```php
namespace Ibexa\Commerce\Shop;
```

### Bundles

The bundle class definition in the `src/bundle` directory must be:

```php
namespace Ibexa\Bundle\<PackageName>;

class Ibexa[ProductGroup]<PackageName>Bundle // ...
```

Examples:

```php
namespace Ibexa\Bundle\Search;

class IbexaSearchBundle // ...
```

```php
namespace Ibexa\Bundle\Commerce\Shop;

class IbexaCommerceShopBundle // ...
```

### Contracts

A package may introduce a namespace for contracts, to be consumed by first and third party packages and projects, which must be prefixed as:

```php
namespace Ibexa\Contracts;
```

Examples:

```php
namespace Ibexa\Contracts\Kernel;
```

```php
namespace Ibexa\Contracts\SiteFactory;
```

```php
namespace Ibexa\Contracts\Commerce\Shop;
```

That namespace needs to be mapped to the `src/contracts` directory of a package.

> **Note: Note**
>
> Backward compatibility for interfaces and objects defined in the `Contracts` namespace is guaranteed.