角色和权限多对多查询出关联的问题?

角色模型:

Position.php

/**
 * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
 */
public function permissions()
{
    return $this->belongsToMany(Permission::class,'position_permission_ref','position_id','permission_id')->withTimestamps();
}

权限模型:

Permission.php

public function positions()
{
    return $this->belongsToMany(Position::class,'position_permission_ref','permission_id','position_id')->withTimestamps();
}

我现在是获取所有的角色列表.需要查询出关联表的权限名称.

使用你说的方法

<?php

namespace App\Transformers;

use App\Models\Position;
use League\Fractal\TransformerAbstract;

class PositionTransformer extends TransformerAbstract {

    protected $availableIncludes = ['permissions'];

    public function transform(Position $position)
    {
        return [
            'id'          => $position->id,
            'name'        => $position->name,
            'description' => $position->description,
            'status'      => $position->status,
            'created_at'  => $position->created_at->toDateTimeString(),
            'updated_at'  => $position->updated_at->toDateTimeString(),
        ];
    }

    public function includePermissions(Position $position)
    {
        return $this->item($position->permissions, new PermissionTransformer());
    }

}

报错如下: