balfour/eloquent-dynamic-relationships

A library for monkey patching relationships between Eloquent models at runtime.

You can use this library inside any Laravel application or stand-alone application which uses the Eloquent ORM.

This library is in early release and is pending unit tests.

Use Case

We developed this library when a need arose to bond models separated across multiple packages (and repositories) in an internal modular system.

Let's consider a system such as the following:

• The framework - the brain which glues modules together.
• A user module - a package which allows users to login, register, etc.
• A sms module - a package which allows users to send text messages.

These are 3 separate packages stored in independent repositories which have the bare minimum knowledge of each other.

• The framework knows about both user and sms modules.
• The user module has no dependencies.
• The sms module knows about the user module.

In this system, the Message model can define it's many to one relationship to the User model; however the User model has no context of the sms package and is therefore not capable of defining the inverse one to many relationship back.

eg: $message->user would succeed, but $user->messages or $user->messages()->paginate() would cause an error.

The responbility therefore falls on the framework to monkey patch this inverse relationship on the User model.

Installation

composer require balfour/eloquent-dynamic-relationships

This package only needs to be installed in the repository (or repositories) containing models you want to make monkey patachable.

Usage

Configuring Monkey Patachable Model

The model which you want to make monkey patchable needs to either extend our base model, or use the HasDynamicRelationships trait.

Method 1 (preferred)

namespace SMSModule;

use Balfour\EloquentDynamicRelationships\HasDynamicRelationships;
use Illuminate\Database\Eloquent\Model;

class Message extends Model
{
    use HasDynamicRelationships;
    
    //
}

Method 2

namespace SMSModule;

use Balfour\EloquentDynamicRelationships\Model;

class Message extends Model
{
    //   
}

Creating Dynamic Relationship

In your framework codebase which glues everything together, you'll need to bond the two models together. This should typically be done at a bootstrap stage, such as when your app's AppServiceProvider is booted.

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use SMSModule\Message;
use UserModule\User;

class AppServiceProvider extends ServiceProvider
{
    /**
     * Register any application services.
     *
     * @return void
     */
    public function register()
    {
        //
    }

    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        UserModule::bond('messages', function () {
            return $this->hasMany(Message::class);
        });
    }
}

With the bond established between the 2 models, you can now use relationship calls as per normal.

eg:

use SMSModule\Message;
use UserModule\User;

$user = User::find(1);

// retrieve a user's messages
$messages = $user->messages;

// retrieve and sort a user's messages by send date
$messages = $user->messages()
    ->latest('send_date')
    ->get();
    
// paginate a user's messages
$messages = $user->messages()
    ->paginate();

// get the user who sent the message
$message = Message::first();
$user = $message->user;

Other Methods

use UserModule\User;

// destroy a bond between 2 models
User::breakup('activities');

// retrieve all dynamic bonds
$bonds = User::getBonds();

// determine if a model is bonded with another
User::isBondedWith('activities');