Not able to get protected `_junctionTableName`

[mehov]

Description

I have a belongsToMany association in TagsTable.php. In case it's important, it happens to be an association with itself. (Please don't ask why.)

$this->belongsToMany('Tags', [
    'foreignKey' => 'tag_id',
    'targetForeignKey' => 'tag_id',
    'joinTable' => 'tags_tags',
]);

Inside some method in the same TagsTable class I need to know the database name of the table they are associated through (tags_tags).

debug($this->getAssociation('Tags'));

object(Cake\ORM\Association\BelongsToMany) id:0 {
    protected _joinType => 'INNER'
    protected _strategy => 'select'
    protected _junctionTable => null
    protected _junctionTableName => 'tags_tags'
    protected _junctionAssociationName => null
    protected _junctionProperty => '_joinData'
    protected _saveStrategy => 'replace'
    protected _targetForeignKey => 'tag_id'
    protected _through => null
    protected _validStrategies => [ ]
    protected _dependent => true
    protected _targetConditions => null
    protected _junctionConditions => null
    protected _sort => null
    protected _name => 'Tags'
    protected _className => 'Tags'
    protected _bindingKey => null
    protected _foreignKey => 'tag_id'
    protected _conditions => [ ]
    protected _cascadeCallbacks => false
    protected _sourceTable => object(App\Model\Table\TagsTable) id:1 { }
    protected _targetTable => null
    protected _propertyName => null
    protected _finder => 'all'
    protected defaultTable => null
    protected _tableLocator => object(Cake\ORM\Locator\TableLocator) id:2 { }
}

So I need what's inside _junctionTableName, but I can't get it. There's no method to access that protected property listed on https://api.cakephp.org/4.4/class-Cake.ORM.Association.BelongsToMany.html and trying all combinations of $this->getAssociation('Tags')->junctionTableName() and $this->getAssociation('Tags')->getJunctionTableName() result in an error saying Unknown method.

CakePHP Version

4.4.14

PHP Version

No response

[kojot1234]

There's a public function junction, that's probably what you are looking for. $this->getAssociation('Tags')->junction()

[mehov]

@kojot1234 thank you for replying.

I did try it, but I got another error

The Tags association on Tags cannot target the same table. InvalidArgumentException

Another problem with it is that over the last few years CakePHP has been moving to setSomething()/getSomething() and deprecating something(), so to me junction() felt like a candidate for deprecation that shouldn't be used anyway. So I didn't even mention it here

[kojot1234]

Sounds to me like you need to provide a different alias for your association.

$this->belongsToMany('ChildTags', [
    'className' => 'Tags',
    'foreignKey' => 'tag_id',
    'targetForeignKey' => 'tag_id',
    'joinTable' => 'tags_tags',
]);

[mehov]

That worked. Thank you!