Foreign key configuration for BelongsTo or HasMany relationship.

[scaabel]

Description

To have a centralized foreign key configuration for relationships. In the tenancy config, we can add a key to specify the value of the foreign key to reference the tenant's column.

// tenancy.php

'foreign_keys'  => [
    'tenant' => 'tenant_id'
]

Why this should be added

I'm currently using uuid as the primary key for tenants and based on the documentation to override the default tenant_id foreign key, we need to change BelongsToTenant::$tenantIdColumn. I noticed that the HasDomains trait is specifically defining the foreign key as tenant_id.

// Concerns/HasDomains
/**
 * @property-read Domain[]|\Illuminate\Database\Eloquent\Collection $domains
 */
trait HasDomains
{
    public function domains()
    {
        return $this->hasMany(config('tenancy.domain_model'), 'tenant_id') <---- specifying tenant_id ;
    }

// ...rest of code
}

If we were to implement a configurable foreign key in the tenancy config file. We can perhaps do something like.

// Concerns/HasDomains
/**
 * @property-read Domain[]|\Illuminate\Database\Eloquent\Collection $domains
 */
trait HasDomains
{
    public function domains()
    {
        return $this->hasMany(config('tenancy.domain_model'), config('tenancy.foreign_keys.tenant');
    }

// ...rest of code
}

// Concerns/BelongsToTenant
/**
 * @property-read Tenant $tenant
 */
trait BelongsToTenant
{
    public function tenant()
    {
        return $this->belongsTo(config('tenancy.tenant_model'), config('tenancy.foreign_keys.tenant'));
    }

    public static function bootBelongsToTenant()
    {
        static::addGlobalScope(new TenantScope);

        static::creating(function ($model) {
            if (! $model->getAttribute(config('tenancy.foreign_keys.tenant')) && ! $model->relationLoaded('tenant')) {
                if (tenancy()->initialized) {
                    $model->setAttribute(config('tenancy.foreign_keys.tenant'), tenant()->getTenantKey());
                    $model->setRelation('tenant', tenant());
                }
            }
        });
    }
}

[stancl]

I see, seems like the HasDomains trait should be using something like BelongsToTenant::$tenantIdColumn as well instead of the literal tenant_id string.

We changed this in v4 to use a config key instead of a trait property, since PHP 8.1 shows deprecation notices when you try to access trait properties (#854): 24146b2

But I see your point that this relates to HasDomains as well, and not just single-db Tenancy traits/columns.

The change you proposed to BelongsToTenant seems to be fully implemented here already (correct me if I'm wrong): 24146b2#diff-3f95188061d3fafb597105f47adbb923c98d5b4da9a9839c4a944627c5277981R17-R27

And for the HasDomains trait, you can currently just override the method, but I agree that we should add a config key.

[stancl]

Thanks for opening the issue!

[scaabel]

I see, seems like the HasDomains trait should be using something like BelongsToTenant::$tenantIdColumn as well instead of the literal tenant_id string.

We changed this in v4 to use a config key instead of a trait property, since PHP 8.1 shows deprecation notices when you try to access trait properties (#854): 24146b2

But I see your point that this relates to HasDomains as well, and not just single-db Tenancy traits/columns.

The change you proposed to BelongsToTenant seems to be fully implemented here already (correct me if I'm wrong): 24146b2#diff-3f95188061d3fafb597105f47adbb923c98d5b4da9a9839c4a944627c5277981R17-R27

And for the HasDomains trait, you can currently just override the method, but I agree that we should add a config key.

Thanks @stancl .