Devise\Pages\Collections\CollectionsManager::createNewInstanceField PHP Method

    public function createNewInstanceField($instance, $fieldInput)
    {
        $field = $this->Field->newInstance();
        $field->collection_instance_id = $instance->id;
        $field->page_version_id = $instance->page_version_id;
        $field->type = $fieldInput['type'];
        $field->key = $fieldInput['key'];
        $field->human_name = $fieldInput['human_name'];
        $field->json_value = array_get($fieldInput, 'json_value', '{}');
        $field->content_requested = array_get($fieldInput, 'content_requested', false) == 1;
        $field->save();
        return $field;
    }