Php 如何向Laravel中雄辩的模型对象集合添加元字段
我有一个设备模型和一个读数模型,它们通过多对多关系连接起来。我正在开发一个API,它将所有注册设备的数组返回给特定用户。我想要的是响应中的一个字段,它显示读数表中的最后一个条目 这是返回响应的方法。Php 如何向Laravel中雄辩的模型对象集合添加元字段,php,json,laravel,laravel-5,eloquent,Php,Json,Laravel,Laravel 5,Eloquent,我有一个设备模型和一个读数模型,它们通过多对多关系连接起来。我正在开发一个API,它将所有注册设备的数组返回给特定用户。我想要的是响应中的一个字段,它显示读数表中的最后一个条目 这是返回响应的方法。 public function getUserDevices($user_id){ $devices = Device::where('user_id',$user_id)->get(); return response()->json($devices); } [
public function getUserDevices($user_id){
$devices = Device::where('user_id',$user_id)->get();
return response()->json($devices);
}
[
{
"id": 2,
"user_id": 1,
"device_name": "My Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:39:35",
"updated_at": "2018-05-13 17:56:56",
"device_key": "60:01:94:37:D1:34",
"actuator": 0,
"mode": 1
},
{
"id": 3,
"user_id": 1,
"device_name": "Home Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:40:25",
"updated_at": "2018-05-12 13:42:00",
"device_key": "60:01:94:37:D1:35",
"actuator": 0,
"mode": 0
}
]
[
{
"id": 2,
"user_id": 1,
"device_name": "My Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:39:35",
"updated_at": "2018-05-13 17:56:56",
"device_key": "60:01:94:37:D1:34",
"actuator": 0,
"mode": 1
"reading":{ <--- This is what i want in every item of the collection
"temp": 45,
"hum" : 60
}
},
{
"id": 3,
"user_id": 1,
"device_name": "Home Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:40:25",
"updated_at": "2018-05-12 13:42:00",
"device_key": "60:01:94:37:D1:35",
"actuator": 0,
"mode": 0
"reading":{ <--- This is what i want in every item of the collection
"temp": 35,
"hum" : 76
}
}
]
我目前得到的回应。
public function getUserDevices($user_id){
$devices = Device::where('user_id',$user_id)->get();
return response()->json($devices);
}
[
{
"id": 2,
"user_id": 1,
"device_name": "My Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:39:35",
"updated_at": "2018-05-13 17:56:56",
"device_key": "60:01:94:37:D1:34",
"actuator": 0,
"mode": 1
},
{
"id": 3,
"user_id": 1,
"device_name": "Home Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:40:25",
"updated_at": "2018-05-12 13:42:00",
"device_key": "60:01:94:37:D1:35",
"actuator": 0,
"mode": 0
}
]
[
{
"id": 2,
"user_id": 1,
"device_name": "My Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:39:35",
"updated_at": "2018-05-13 17:56:56",
"device_key": "60:01:94:37:D1:34",
"actuator": 0,
"mode": 1
"reading":{ <--- This is what i want in every item of the collection
"temp": 45,
"hum" : 60
}
},
{
"id": 3,
"user_id": 1,
"device_name": "Home Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:40:25",
"updated_at": "2018-05-12 13:42:00",
"device_key": "60:01:94:37:D1:35",
"actuator": 0,
"mode": 0
"reading":{ <--- This is what i want in every item of the collection
"temp": 35,
"hum" : 76
}
}
]
我想要的回应。
public function getUserDevices($user_id){
$devices = Device::where('user_id',$user_id)->get();
return response()->json($devices);
}
[
{
"id": 2,
"user_id": 1,
"device_name": "My Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:39:35",
"updated_at": "2018-05-13 17:56:56",
"device_key": "60:01:94:37:D1:34",
"actuator": 0,
"mode": 1
},
{
"id": 3,
"user_id": 1,
"device_name": "Home Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:40:25",
"updated_at": "2018-05-12 13:42:00",
"device_key": "60:01:94:37:D1:35",
"actuator": 0,
"mode": 0
}
]
[
{
"id": 2,
"user_id": 1,
"device_name": "My Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:39:35",
"updated_at": "2018-05-13 17:56:56",
"device_key": "60:01:94:37:D1:34",
"actuator": 0,
"mode": 1
"reading":{ <--- This is what i want in every item of the collection
"temp": 45,
"hum" : 60
}
},
{
"id": 3,
"user_id": 1,
"device_name": "Home Device",
"device_type": "Sensor",
"status": 1,
"created_at": "2018-05-01 14:40:25",
"updated_at": "2018-05-12 13:42:00",
"device_key": "60:01:94:37:D1:35",
"actuator": 0,
"mode": 0
"reading":{ <--- This is what i want in every item of the collection
"temp": 35,
"hum" : 76
}
}
]
[
{
“id”:2,
“用户id”:1,
“设备名称”:“我的设备”,
“设备类型”:“传感器”,
“地位”:1,
“创建时间”:“2018-05-01 14:39:35”,
“更新时间”:“2018-05-13 17:56:56”,
“设备密钥”:“60:01:94:37:D1:34”,
“执行器”:0,
“模式”:1
“阅读”:{你可以通过以下方式做到这一点:
public function getUserDevices($user_id){
$devices = Device::with('reading')->where('user_id',$user_id)->get();
return response()->json($devices);
}
您应该能够创建一个将结果限制为最新结果的关系,如下所示
public function latestReading()
{
return $this->belongsToMany('Reading')
->orderBy('created_at', 'DESC')
->limit(1)
->first();
}
$devices = Device::with('latestReading')->where('user_id',$user_id)->get();
或: