Repeatable has many relationship. How do I set this up?

[NuktukDev]

My client wants to be able to add many "items" to an entity.

Think about an invoice, and invoice lines. The invoice has many lines.

Invoice:

• id
• client_name
• client_email

Invoice Lines:

• id
• invoice_id
• service (ie: Web Services)
• price

I have a repeatable field that lets you add the service text ("Web Services" for example) and the price, and then you can add another line with the same fields.

I'm trying to get it to save these lines on the invoice model, as well as display them in the update operation.

My invoice model has a hasMany relationship with the lines.

Here is how I'm trying to set it up:

CRUD::field([ 
            'name'  => 'lines',
            'label' => 'Invoice Items',
            'type'  => 'repeatable',
            'subfields' => [
                [
                   'name' => 'service',
                    'allows_null' => false,
                    'label' => 'Service',
                    'type' => 'text',
                ],
                 [
                   'name' => 'price',
                    'allows_null' => false,
                    'label' => 'Price',
                    'type' => 'number',
                ],
            ],
        
            // optional
            'new_item_label'  => 'Add Invoice Item', // customize the text of the button
            'init_rows' => 1, // number of empty rows to be initialized, by default 1
            // allow reordering?
        ]);

[backpack-ai-bot[bot]]

To set up a repeatable field for a "has many" relationship like invoice lines in Backpack, you should use the relationship field type instead of the repeatable field type. The relationship field type with subfields is designed specifically for this kind of scenario.

Here's how you can set it up:

CRUD::field([
    'name' => 'lines',
    'label' => 'Invoice Items',
    'type' => 'relationship',
    'subfields' => [
        [
            'name' => 'service',
            'type' => 'text',
            'label' => 'Service',
            'wrapper' => ['class' => 'form-group col-md-6'],
        ],
        [
            'name' => 'price',
            'type' => 'number',
            'label' => 'Price',
            'attributes' => ["step" => "any"],
            'wrapper' => ['class' => 'form-group col-md-6'],
        ],
    ],
    'new_item_label' => 'Add Invoice Item',
]);

This setup will allow you to add, edit, and delete invoice lines directly within the invoice form. The relationship field type will handle saving the related models (invoice lines) when the parent model (invoice) is saved.

Here are some key points to note:

1. The type is set to relationship instead of repeatable.
2. The name should match the relationship method name in your Invoice model (e.g., lines()).
3. The subfields define the fields for each invoice line.
4. You can customize the layout using wrapper classes for each subfield.

Make sure you have properly set up the relationship in your Invoice model:

public function lines()
{
    return $this->hasMany(InvoiceLine::class);
}

And in your InvoiceLine model:

public function invoice()
{
    return $this->belongsTo(Invoice::class);
}

This setup will automatically handle saving the related invoice lines when you save the invoice, and it will also display the existing lines in the update operation.

Source: Backpack Docs - Relationship Field

Remember that you cannot use a repeatable field inside another repeatable or relationship field, as mentioned in the Backpack documentation.

Relevant sources:

Github Issue (open): [Bug] Upload subfield contains wrong url in repeteable relationship field
Github Issue (closed): [4.2][Bug] Relationships don't get saved for subfields
Fields|repeatable PRO Part 1
Fields|Manage related entries in the same form (create, update, delete) Part 1
Github Issue (closed): [Bug] Repeatable field with belongsToMany relationship not saving data
Github Issue (closed): [Feature Request] [4.1.0] Repeatable field (non-pivot) - save in database
Github Issue (closed): [4.2][Bug] Relationships don't get saved for subfields
Github Issue (closed): [Bug] Error when trying to save a subfield in a relationship field
Use of Repeatable inside Relationship
Github Issue (closed): [Bug] error with null relationships
Github Issue (closed): [Feature or Documentation Request] - CrudField JavaScript Library with relationship/subfield fields
Multiple relationship fields
Github Issue (closed): [Bug] Repeatable field with belongsToMany relationship not saving data
Github Issue (closed): [Bug] Repeatable with field select2_multiple and relations
Use of Repeatable inside Relationship