Implementing Repositories

Overview

Repositories abstract persistence behind domain contracts. The contract interface lives in Domain/Contracts/; the Eloquent implementation lives in Infrastructure/Persistence/. Repositories handle persistence only — they never publish events (that's the use case's job).

Repository Contract

Every aggregate root has a repository contract with four standard methods:

declare(strict_types=1);

namespace App\CustomerRelationshipManagement\Contacts\Domain\Contracts;

use App\CustomerRelationshipManagement\Contacts\Domain\Contact;
use ComplexHeart\Domain\Criteria\Criteria;
use Illuminate\Pagination\LengthAwarePaginator;

interface ContactRepository
{
    public function find(string $id): ?Contact;

    public function match(Criteria $criteria): LengthAwarePaginator;

    public function save(Contact $contact): Contact;

    public function delete(Contact $contact): void;
}

Rules:

• Named {Entity}Repository — always an interface
• Four standard methods: find, match, save, delete
• find() returns nullable entity — never throws (the use case handles not-found logic)
• match() accepts Criteria and returns LengthAwarePaginator for paginated results
• save() returns the persisted entity
• delete() returns void
• No custom query methods (e.g., findByEmail()) — use match() with criteria instead
• Placement: {Module}/Domain/Contracts/

Read-Only Contract

When an entity is a read projection or lookup-only, omit save() and delete():

interface ManagerRepository
{
    public function find(string $id): ?Manager;

    public function match(Criteria $criteria): LengthAwarePaginator;
}

Eloquent Implementation

Standard Implementation

declare(strict_types=1);

namespace App\CustomerRelationshipManagement\Contacts\Infrastructure\Persistence;

use App\CustomerRelationshipManagement\Contacts\Domain\Contact;
use App\CustomerRelationshipManagement\Contacts\Domain\Contracts\ContactRepository;
use ComplexHeart\Domain\Criteria\Criteria;
use ComplexHeart\Infrastructure\Laravel\EloquentCriteriaParser;
use Illuminate\Pagination\LengthAwarePaginator;

class EloquentContactRepository implements ContactRepository
{
    public function find(string $id): ?Contact
    {
        return Contact::find($id);
    }

    public function match(Criteria $criteria): LengthAwarePaginator
    {
        $parser = new EloquentCriteriaParser([], true);

        return $parser->applyCriteria(Contact::query(), $criteria);
    }

    public function save(Contact $contact): Contact
    {
        $contact->save();

        return $contact;
    }

    public function delete(Contact $contact): void
    {
        $contact->delete();
    }
}

With Eager Loading

Load relationships when needed for performance:

public function find(string $id): ?Visa
{
    return Visa::with('applicant')->find($id);
}

public function match(Criteria $criteria): LengthAwarePaginator
{
    $parser = new EloquentCriteriaParser([], true);

    return $parser->applyCriteria(
        Visa::query()->with('applicant'),
        $criteria
    );
}

With Field Mapping

Map domain field names to database column names in the criteria parser:

public function match(Criteria $criteria): LengthAwarePaginator
{
    $parser = new EloquentCriteriaParser([
        'name' => 'first_name',
        'account' => 'account_id',
    ], true);

    return $parser->applyCriteria(Contact::query(), $criteria);
}

With Cross-Table Joins

When filtering requires data from related tables:

public function match(Criteria $criteria): LengthAwarePaginator
{
    $query = Visa::with('applicant')
        ->select('vm_visas.*')
        ->join('crm_contacts', 'vm_visas.applicant_id', '=', 'crm_contacts.id');

    $parser = new EloquentCriteriaParser([
        'id' => 'vm_visas.id',
        'account' => 'crm_contacts.account_id',
        'applicant' => 'vm_visas.applicant_id',
    ], true);

    return $parser->applyCriteria($query, $criteria);
}

With Delete Cleanup

When deletion requires cleaning up related data:

public function delete(User $user): void
{
    $user->deleteProfilePhoto();
    $user->tokens->each->delete();
    $user->delete();
}

public function delete(CustomAttributeGroup $group): void
{
    $group->attributes()->delete();
    $group->delete();
}

With Exception Translation

Convert database exceptions to domain exceptions:

use App\CustomerRelationshipManagement\Documents\Domain\Exceptions\DocumentException;
use App\CustomerRelationshipManagement\Documents\Domain\Exceptions\InvalidOwnerReference;
use PDOException;

public function save(Document $document): Document
{
    try {
        $document->save();

        return $document;
    } catch (PDOException $e) {
        match ($e->getCode()) {
            '23000' => throw new InvalidOwnerReference('Invalid owner reference.'),
            default => throw new DocumentException("Unable to persist the document due to: {$e->getMessage()}"),
        };
    }
}

Placement: {Module}/Infrastructure/Persistence/

Criteria System

The match() method uses ComplexHeart\Domain\Criteria\Criteria with EloquentCriteriaParser to translate domain queries into Eloquent queries.

EloquentCriteriaParser

$parser = new EloquentCriteriaParser(
    fieldMapping: ['domainField' => 'database_column'],
    paginate: true,
);

return $parser->applyCriteria($query, $criteria);

Constructor parameters:

What the parser handles automatically:

• Filtering (where clauses from criteria filters)
• Sorting (order by from criteria order)
• Pagination (page + per-page from criteria)

Field Mapping Examples

// No mapping needed — domain and database names match
new EloquentCriteriaParser([], true);

// Simple renames
new EloquentCriteriaParser([
    'name' => 'first_name',
    'account' => 'account_id',
], true);

// Qualified columns for joins
new EloquentCriteriaParser([
    'id' => 'vm_visas.id',
    'account' => 'crm_contacts.account_id',
], true);

ServiceProvider Binding

Repository contracts are bound to implementations in the bounded context's ServiceProvider via the $bindings array:

class CustomerRelationshipManagementServiceProvider extends ServiceProvider
{
    public array $bindings = [
        ContactRepository::class => EloquentContactRepository::class,
        ManagerRepository::class => EloquentManagerRepository::class,
        DocumentRepository::class => EloquentDocumentRepository::class,
    ];
}

Laravel resolves these automatically via constructor injection in use cases. See configuring-bounded-contexts for full ServiceProvider details.

Common Mistakes

Pre-flight Checklist

• Contract interface in {Module}/Domain/Contracts/{Entity}Repository.php?
• Four standard methods: find, match, save, delete?
• find() returns nullable entity (never throws)?
• match() uses Criteria and returns LengthAwarePaginator?
• Eloquent implementation in {Module}/Infrastructure/Persistence/?
• EloquentCriteriaParser configured with field mapping?
• No event publishing in repository methods?
• Delete method cleans up related data if needed?
• Contract bound in the context's ServiceProvider $bindings?

Laravel Reference

This skill uses Laravel-specific features. Consult the official Laravel documentation (via Context7 or web search) for details on:

• Illuminate\Pagination\LengthAwarePaginator — paginated query results
• Illuminate\Database\Eloquent\Builder — Eloquent query builder (query(), with(), find(), where())
• Illuminate\Database\Eloquent\Model::save() — persisting model state
• complexheart/laravel-criteria — Criteria pattern for domain-driven querying (see package docs)