ManagesManyToMany Trait - Rest Generic Class

Overview

The ManagesManyToMany trait provides complete CRUD functionality for many-to-many (BelongsToMany) relationships with support for:

Reading related records with filtering, pagination, and sorting
Creating related records through the relationship
Updating related records and pivot data
Deleting related records and pivot associations
Attaching/detaching existing records
Syncing and toggling associations
Bulk operations for all mutation methods
Excel/PDF export of related data

Namespace: Ronu\RestGenericClass\Core\Traits\ManagesManyToMany Location: /src/Core/Traits/ManagesManyToMany.php:40

Configuration

Basic Setup

Add the trait to your controller and define $manyToManyConfig:

use Ronu\RestGenericClass\Core\Traits\ManagesManyToMany;

class UserController extends RestController
{
    use ManagesManyToMany;
    
    protected array $manyToManyConfig = [
        'addresses' => [
            'relationship'  => 'array_address',      // BelongsToMany method on parent
            'relatedModel'  => Address::class,
            'pivotModel'    => UserAddress::class,
            'parentModel'   => User::class,
            'parentKey'     => 'user_id',
            'relatedKey'    => 'address_id',
            
            'mutation' => [
                'dataKey'       => ['Addresses', 'addresses'],
                'deleteRelated' => true,
                'pivotColumns'  => ['is_primary', 'label'],
            ],
        ],
    ];
}

Configuration Options

Required

relationship (string) - Name of the BelongsToMany method on the parent model
relatedModel (string) - Fully qualified class name of the related model
pivotModel (string) - Pivot table model class
parentModel (string) - Parent model class name
parentKey (string) - Foreign key column in pivot table for parent
relatedKey (string) - Foreign key column in pivot table for related model

Optional (mutation)

dataKey (array|string) - Request keys to extract data from (default: [])
deleteRelated (bool) - Delete related model on deleteRelation (default: true)
pivotColumns (array) - Whitelist of allowed pivot columns (default: [] = all)

Read Operations

listRelation

List related entities with filtering, pagination, and sorting.

public function listRelation(Request $request, mixed $parentId = null): LengthAwarePaginator|array

Parameters

Request $request - HTTP request with query parameters
mixed $parentId - Parent ID (null = auth user)

Query Parameters

select - Columns to select (default: ['*'])
relations - Relations to eager-load
eq/attr - Equality filters
oper - Complex filters (see Filtering)
orderby - Sort order
pagination - Pagination settings

Example

GET /api/users/1/addresses?select=id,street,city&orderby={"city":"asc"}&pagination={"page":1,"pageSize":20}

Response:

{
  "current_page": 1,
  "data": [
    {
      "id": 5,
      "street": "123 Main St",
      "city": "Boston",
      "pivot": {
        "user_id": 1,
        "address_id": 5,
        "is_primary": true,
        "label": "Home"
      }
    }
  ],
  "per_page": 20,
  "total": 3
}

showRelation

Retrieve a single related entity.

public function showRelation(
    Request $request, 
    mixed $parentIdOrRelatedId, 
    mixed $relatedId = null
): mixed

Parameters

Request $request - HTTP request
mixed $parentIdOrRelatedId - Parent ID (admin) or related ID (site/mobile)
mixed $relatedId - Related ID (admin only)

Route Shapes

// Site/Mobile: uses auth user as parent
GET /addresses/5

// Admin: explicit parent ID
GET /users/1/addresses/5

Returns

Related model instance on success
404 JSON response if not found

Example Response (Not Found)

{
  "success": false,
  "error": {
    "message": "Address with id 99 not found in relation 'addresses'",
    "relation": "addresses",
    "id": 99,
    "suggested_fix": "Verify the resource exists via GET on the 'addresses' endpoint before performing write operations on it."
  }
}

Create Operations

createRelation

Create new related entities through the relationship.

public function createRelation(Request $request, mixed $parentId = null): JsonResponse

Single Mode

Route: POST /users/1/addresses Request:

{
  "addresses": {
    "street": "456 Oak Ave",
    "city": "Chicago",
    "is_primary": false
  }
}

Response (201):

{
  "success": true,
  "model": {
    "id": 10,
    "street": "456 Oak Ave",
    "city": "Chicago"
  }
}

Bulk Mode

Set _scenario to any value containing “bulk”: Route: POST /users/1/addresses?_scenario=bulk_create Request:

{
  "addresses": [
    {"street": "789 Elm St", "city": "Austin"},
    {"street": "321 Pine Rd", "city": "Denver"}
  ]
}

Response (201):

{
  "success": true,
  "models": [
    {"id": 11, "street": "789 Elm St", "city": "Austin"},
    {"id": 12, "street": "321 Pine Rd", "city": "Denver"}
  ]
}

Update Operations

updateRelation

Update related entities.

public function updateRelation(
    Request $request, 
    mixed $parentIdOrRelatedId = null, 
    mixed $relatedId = null
): JsonResponse

Single Mode

Route: PUT /users/1/addresses/5 Request:

{
  "street": "Updated Street",
  "city": "New City"
}

Response:

{
  "success": true,
  "model": {
    "id": 5,
    "street": "Updated Street",
    "city": "New City"
  }
}

Bulk Mode

Route: PUT /users/1/addresses?_scenario=bulk_update Request:

{
  "addresses": [
    {"id": 5, "city": "Boston"},
    {"id": 6, "city": "Seattle"}
  ]
}

Response:

{
  "success": true,
  "models": [
    {"id": 5, "city": "Boston"},
    {"id": 6, "city": "Seattle"}
  ]
}

Delete Operations

deleteRelation

Delete related entities and optionally detach pivot.

public function deleteRelation(
    Request $request, 
    mixed $parentIdOrRelatedId = null, 
    mixed $relatedId = null
): JsonResponse

Configuration

'mutation' => [
    'deleteRelated' => true,  // Delete model + detach pivot
    // OR
    'deleteRelated' => false, // Only detach pivot (keep model)
]

Single Mode

Route: DELETE /users/1/addresses/5 Response:

{
  "success": true,
  "model": {
    "id": 5,
    "street": "123 Main St"
  }
}

Bulk Mode

Route: DELETE /users/1/addresses?_scenario=bulk_delete Request:

{
  "address_ids": [5, 6, 7]
}

Or flat array:

[5, 6, 7]

Response:

{
  "success": true,
  "models": [
    {"id": 5},
    {"id": 6},
    {"id": 7}
  ]
}

Attach/Detach Operations

attachRelation

Attach existing related entities (pivot-only operation).

public function attachRelation(Request $request, mixed $parentId = null): JsonResponse

Scenarios

attach - Single ID with optional pivot data
bulk_attach - Multiple IDs with optional pivot data
sync - Replace entire relationship set
toggle - Toggle specific IDs

Single Attach

Route: POST /users/1/addresses/attach?_scenario=attach Request:

{
  "address_id": 10,
  "is_primary": true,
  "label": "Work"
}

Response:

{
  "attached": [10]
}

Bulk Attach

Route: POST /users/1/addresses/attach?_scenario=bulk_attach Request (with pivot data):

{
  "addresses": [
    {"address_id": 11, "is_primary": false, "label": "Home"},
    {"address_id": 12, "is_primary": false, "label": "Office"}
  ]
}

Or flat IDs:

{
  "addresses": [11, 12, 13]
}

Response:

{
  "attached": [11, 12, 13]
}

Sync

Replaces all associations: Route: POST /users/1/addresses/attach?_scenario=sync Request:

{
  "addresses": [
    {"address_id": 5, "is_primary": true},
    {"address_id": 8, "is_primary": false}
  ]
}

Response:

{
  "attached": [8],
  "detached": [6, 7],
  "updated": [5]
}

Toggle

Attach if not present, detach if present: Route: POST /users/1/addresses/attach?_scenario=toggle Request:

{
  "addresses": [5, 10, 15]
}

Response:

{
  "attached": [10],
  "detached": [5, 15]
}

detachRelation

Detach related entities (pivot-only removal).

public function detachRelation(
    Request $request, 
    mixed $parentIdOrRelatedId = null, 
    mixed $relatedId = null
): JsonResponse

Single Detach

Route: DELETE /users/1/addresses/5/detach Response:

{
  "detached": 1
}

Bulk Detach

Route: DELETE /users/1/addresses/detach?_scenario=bulk_detach Request:

[5, 6, 7]

Response:

{
  "detached": 3
}

updatePivotRelation

Update pivot table fields without modifying related model.

public function updatePivotRelation(
    Request $request, 
    mixed $parentIdOrRelatedId = null, 
    mixed $relatedId = null
): JsonResponse

Single Mode

Route: PUT /users/1/addresses/5/pivot Request:

{
  "is_primary": true,
  "label": "Primary Address"
}

Response:

{
  "id": 5,
  "street": "123 Main St",
  "pivot": {
    "is_primary": true,
    "label": "Primary Address"
  }
}

Bulk Mode

Route: PUT /users/1/addresses/pivot?_scenario=bulk_update_pivot Request:

{
  "addresses": [
    {"address_id": 5, "is_primary": true},
    {"address_id": 6, "is_primary": false}
  ]
}

Export Operations

exportRelationExcel

Export related data to Excel.

public function exportRelationExcel(Request $request, mixed $parentId = null): mixed

Parameters

filename (string) - Output filename (default: 'export.xlsx')
columns (array|CSV) - Explicit columns for spreadsheet
select, eq, oper, orderby, relations - Same as listRelation

Example

GET /users/1/addresses/export/excel?filename=user-addresses.xlsx&columns=street,city,postal_code

Requires: maatwebsite/excel package

exportRelationPdf

Export related data to PDF.

public function exportRelationPdf(Request $request, mixed $parentId = null): mixed

Parameters

filename (string) - Output filename (default: 'export.pdf')
template (string) - Blade view name (default: 'pdf')
columns, select, eq, oper, orderby, relations - Same as listRelation

Example

GET /users/1/addresses/export/pdf?filename=addresses.pdf&template=reports.address

Requires: barryvdh/laravel-dompdf package

Pivot Data Handling

The trait supports three input shapes for pivot data:

Shape 1: Flat ID List

[1, 2, 3]

Normalized to:

[1 => [], 2 => [], 3 => []]

Shape 2: Object List

[
  {"address_id": 1, "is_primary": true, "label": "Home"},
  {"address_id": 2, "is_primary": false, "label": "Work"}
]

Normalized to:

[
  1 => ["is_primary" => true, "label" => "Home"],
  2 => ["is_primary" => false, "label" => "Work"]
]

Shape 3: Laravel-Native Map

{
  "1": {"is_primary": true},
  "2": {"is_primary": false}
}

Passed through unchanged.

Pivot Column Whitelist

'mutation' => [
    'pivotColumns' => ['is_primary', 'label', 'order'],
]

Only these columns are accepted. Others are silently ignored.

Error Handling

Not Found (Single)

Returns 404 JSON:

{
  "success": false,
  "error": {
    "message": "Address with id 99 not found in relation 'addresses'",
    "relation": "addresses",
    "id": 99,
    "suggested_fix": "Verify the resource exists via GET on the 'addresses' endpoint before performing write operations on it."
  }
}

Not Found (Bulk)

Partial success with error details:

{
  "success": false,
  "models": [
    {"id": 5, "street": "Found Address"}
  ],
  "error": {
    "message": "2 Address record(s) not found in relation 'addresses': [99, 100]",
    "relation": "addresses",
    "not_found_ids": [99, 100],
    "suggested_fix": "Fetch the current list via GET on the 'addresses' endpoint to obtain valid IDs, then retry with only the existing records."
  }
}

Relation Not Configured

// Throws BadRequestHttpException
"Many-to-many relation 'invalid' is not configured on UserController"

Parent Not Found

// Throws NotFoundHttpException
"User with id 9999 not found"

Query Optimization

The trait implements several optimizations:

Batch loading: Bulk operations load all entities in one query
Batch updates: Uses single detach()/delete() for multiple IDs
Batch refresh: Refreshes all updated entities in one query
Minimal queries: Typical bulk update = 3 queries (load, N updates, refresh)

ManagesOneToMany Trait - One-to-many operations
Relation Loading - Eager-loading relations
Many-to-Many Guide - Detailed usage guide
Bulk Operations Guide - Bulk CRUD examples

Core Classes

Traits

Middleware

Validation Rules

Helpers

​Overview

​Configuration

​Basic Setup

​Configuration Options

​Required

​Optional (mutation)

​Read Operations

​listRelation

​Parameters

​Query Parameters

​Example

​showRelation

​Parameters

​Route Shapes

​Returns

​Example Response (Not Found)

​Create Operations

​createRelation

​Single Mode

​Bulk Mode

​Update Operations

​updateRelation

​Single Mode

​Bulk Mode

​Delete Operations

​deleteRelation

​Configuration

​Single Mode

​Bulk Mode

​Attach/Detach Operations

​attachRelation

​Scenarios

​Single Attach

​Bulk Attach

​Sync

​Toggle

​detachRelation

​Single Detach

​Bulk Detach

​updatePivotRelation

​Single Mode

​Bulk Mode

​Export Operations

​exportRelationExcel

​Parameters

​Example

​exportRelationPdf

​Parameters

​Example

​Pivot Data Handling

​Shape 1: Flat ID List

​Shape 2: Object List

​Shape 3: Laravel-Native Map

​Pivot Column Whitelist

​Error Handling

​Not Found (Single)

​Not Found (Bulk)

​Relation Not Configured

​Parent Not Found

​Query Optimization

​Related Documentation

Build docs developers (and LLMs) love

Overview

Configuration

Basic Setup

Configuration Options

Required

Optional (mutation)

Read Operations

listRelation

Parameters

Query Parameters

Example

showRelation

Parameters

Route Shapes

Returns

Example Response (Not Found)

Create Operations

createRelation

Single Mode

Bulk Mode

Update Operations

updateRelation

Single Mode

Bulk Mode

Delete Operations

deleteRelation

Configuration

Single Mode

Bulk Mode

Attach/Detach Operations

attachRelation

Scenarios

Single Attach

Bulk Attach

Sync

Toggle

detachRelation

Single Detach

Bulk Detach

updatePivotRelation

Single Mode

Bulk Mode

Export Operations

exportRelationExcel

Parameters

Example

exportRelationPdf

Parameters

Example

Pivot Data Handling

Shape 1: Flat ID List

Shape 2: Object List

Shape 3: Laravel-Native Map

Pivot Column Whitelist

Error Handling

Not Found (Single)

Not Found (Bulk)

Relation Not Configured

Parent Not Found

Query Optimization

Related Documentation