MySQL嵌套资源（数据透视表）查看/更新/管理的权限 [英] MySQL nested resources (pivot tables) permission to view/update/manage
问题描述
users transactions tasks
+----+--------+ +----+---------------+ +----+--------+
| id | name | | id | name | | id | name |
+----+--------+ +----+---------------+ +----+--------+
| 1 | User 1 | | 1 | Transaction 1 | | 1 | Task 1 |
| 2 | User 2 | | 2 | Transaction 2 | | 2 | Task 2 |
+----+--------+ +----+---------------+ +----+--------+
templates transaction_user task_transaction
+----+---------------+ +---------+----------------+ +---------+----------------+
| id | name | | user_id | transaction_id | | task_id | transaction_id |
+----+---------------+ +---------+----------------+ +---------+----------------+
| 1 | Template 1 | | 1 | 1 | | 1 | 1 |
| 2 | Template 2 | | 2 | 2 | +---------+----------------+
+----+---------------+ +---------+----------------+
task_template
+---------+-------------+
| task_id | template_id |
+---------+-------------+
| 2 | 2 |
+---------+-------------+
动机：
如果有登录用户，说ID为1的用户，他/她想要查看任务ID 1），然后我想确保ID 1 属于 c>的用户之前，我让他查看它的任务。另外，我需要一些显示属于他的所有任务的用户。任务只是一个模型..我需要处理这一切的所有模型。我在下面分享了我的代码，我太努力了？
Motive:
If there is a logged in user, say user with the ID 1, and he/she wants to see a task (say task with the ID 1) then i want to make sure that the task with ID 1 Belongs to the user before i let him view it. Also i need someway to show user all tasks that belong to him. Task is just one model.. i need to handle this for all models. I have shared my code below, am i trying too hard?
我可能在这里省略了一些细节，所以请随时提出问题。
谢谢。
I may have omitted some details here so please feel free to ask questions. Thanks.
代码
<?php namespace SomeProject\Repositories;
use User;
use Account;
use Task;
use Document;
use Transaction;
use Property;
use DB;
use Respond;
abstract class DbRepository
{
/**
* The many to many relationships are handeled using pivot tables
* We will use this array to figure out relationships and then get
* a particular resource's owner / account
*/
public $pivot_models = array(
'Task' => array(
'Transaction' => 'task_transaction'
),
'Transaction' => array(
'User' => 'transaction_user'
),
'Document' => array(
'Property' => 'document_property',
'Task' => 'document_task',
'Message' => 'document_message'
)
);
public $entity_ids;
public function getOwnersByEntity(array $ids, $entity)
{
$this->entity_ids = [];
$user_ids = [];
$entity = ucfirst(strtolower($entity)); // arrays keys are case sensitive
if( $this->getPivotIds($ids, $entity) )
{
foreach ($this->entity_ids as $entity_name => $entity_ids_arr)
{
$entity_name_lowercase = strtolower($entity_name);
if($entity_name_lowercase != 'user')
{
$user_ids_from_entity = $entity_name::whereIn('id', $entity_ids_arr)
->lists('user_id');
}
else
{
// We already have the IDs if the entity is User
$user_ids_from_entity = $entity_ids_arr;
}
array_push($user_ids, $user_ids_from_entity);
}
$merged_user_ids = call_user_func_array('array_merge', $user_ids);
return array_unique($merged_user_ids);
}
else
{
return $entity::whereIn('id', $ids)->lists('user_id');
}
}
public function getPivotIds(array $ids, $entity)
{
$entity_lowercase = strtolower($entity);
if( array_key_exists($entity, $this->pivot_models) )
{
// Its a pivot model
foreach ($this->pivot_models[$entity] as $related_model => $table) // Transaction, Template
{
$related_model_lowercase = strtolower($related_model);
$this->entity_ids[$related_model] = DB::table($table)
->whereIn($entity_lowercase . '_id', $ids)
->lists($related_model_lowercase . '_id');
if( $this->getPivotIds($this->entity_ids[$related_model], $related_model) )
{
unset($this->entity_ids[$related_model]);
}
}
return true;
}
return false;
}
}
推荐答案
检查如果给定的模型与另一个相关，这是你想要的如果我得到你的权利，所有你需要的是这个微小的方法，使最大的 Eloquent ：
To check if given model is related to another one, which is what you want if I get you right, all you need is this tiny method making the most of Eloquent:
（在 BaseModel ， Entity 适合您）
// usage
$task->isRelatedTo('transactions.users', $id);
// or
$template->isRelatedTo('tasks.transactions.users', Auth::user());
// or any kind of relation:
// imagine this: User m-m Transaction 1-m Item m-1 Group
$group->isRelatedTo('items.transaction.users', $id);
奇怪的事情发生在这里：
The magic happens here:
/**
* Check if it is related to any given model through dot nested relations
*
* @param string $relations
* @param int|\Illuminate\Database\Eloquent\Model $id
* @return boolean
*/
public function isRelatedTo($relations, $id)
{
$relations = explode('.', $relations);
if ($id instanceof Model)
{
$related = $id;
$id = $related->getKey();
}
else
{
$related = $this->getNestedRelated($relations);
}
// recursive closure
$callback = function ($q) use (&$callback, &$relations, $related, $id)
{
if (count($relations))
{
$q->whereHas(array_shift($relations), $callback);
}
else
{
$q->where($related->getQualifiedKeyName(), $id);
}
};
return (bool) $this->whereHas(array_shift($relations), $callback)->find($this->getKey());
}
protected function getNestedRelated(array $relations)
{
$models = [];
foreach ($relations as $key => $relation)
{
$parent = ($key) ? $models[$key-1] : $this;
$models[] = $parent->{$relation}()->getRelated();
}
return end($models);
}
-
检查是否通过 $ id 是一个模型或只是一个id，并准备 $ related 模型及其 $ id 用于回调。如果你没有传递一个对象，Eloquent需要实例化 $ relation （ relation1.relation2.relation3 ... ）链得到我们感兴趣的一个 - 这是在 getNestedRelated（），很简单。
check if passed $id is a model or just an id, and prepares $related model and its $id for use in the callback. If you don't pass an object then Eloquent needs to instantiate all the related models on the $relations (relation1.relation2.relation3...) chain to get the one we are interested in - that's what happens in getNestedRelated(), pretty straightforward.
检查是否通过 $ id 是一个模型或只是一个id，并准备 $ related 模型及其 $ id 用于回调。如果你没有传递一个对象，Eloquent需要实例化 $ relation （ relation1.relation2.relation3 ... ）链得到我们感兴趣的一个 - 这是在 getNestedRelated（），很简单。
check if passed $id is a model or just an id, and prepares $related model and its $id for use in the callback. If you don't pass an object then Eloquent needs to instantiate all the related models on the $relations (relation1.relation2.relation3...) chain to get the one we are interested in - that's what happens in getNestedRelated(), pretty straightforward.
那么我们需要这样做：
// assuming relations 'relation1.relation2.relation3'
$this->whereHas('relation1', function ($q) use ($id) {
$q->whereHas('relation2', function ($q) use ($id) {
$q->whereHas('relation3', function ($q) use ($id) {
$q->where('id', $id);
});
});
})->find($this->getKey());
// returns new instance of current model or null, thus cast to (bool)
因为我们不知道关系是如何嵌套的，所以我们需要使用递归。然而，我们传递一个Closure到 whereHas ，所以我们需要使用一点技巧，以便在它的身体内调用自己（事实上我们不叫它，而是传递它作为 $ callback 到 whereHas 方法，因为后者期望Closure作为第二参数） - this可能对那些不熟悉的匿名递归PHP函数非常有用：
since we don't know how deeply the relation is nested, we need to use recurrency. However we pass a Closure to the whereHas, so we need to use little trick in order to call itself inside its body (in fact we don't call it, but rather pass it as $callback to the whereHas method, since the latter expects a Closure as 2nd param) - this might be useful for those unfamiliar Anonymous recursive PHP functions:
// save it to the variable and pass it by reference
$callback = function () use (&$callback) {
if (...) // call the $callback again
else // finish;
}
我们也传递给闭包 $关系（作为数组现在）通过引用为了不移动其元素，当我们得到它们所有（意味着我们嵌套 whereHas ）最后把放在而不是另一个 whereHas 来搜索我们的 $ related 模型。
we also pass to the closure $relations (as an array now) by reference in order to unshift its elements, and when we got them all (meaning we nested whereHas), we finally put the where clause instead of another whereHas, to search for our $related model.
最后让我们返回 bool
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