範圍功能Laravel ORM調用關係

Question

我想從我的客戶表的關係加載到我的訂單表，但每一次我嘗試我不斷收到此錯誤：

Symfony \ Component \ Debug \ Exception \ FatalErrorException Call to a member function where() on a non-object

這裏是我的訂單模式

class Orders extends Eloquent 
{ 
    protected $softDelete = true; 

    public function order_items() 
    { 
     return $this->hasMany('Order_item'); 
    } 

    public function customer() 
    { 
     return $this->hasOne('Customer', 'id', 'customer_id'); 
    } 

    public function client() 
    { 
     return $this->hasOne('Client', 'id', 'client_id'); 
    } 

    public function billingAddress() 
    { 
     if($this->client()->first() != null) 
     { 
      return $this->client()->getBillingAddress($this->billing_address_id); 
     } 
     else 
     { 
      return $this->customer()->getBillingAddress($this->billing_address_id); 
     } 
    } 
} 

這裏是我的客戶模型

class Customer extends Eloquent 
{ 
    protected $softDelete = true; 

    public function order() 
    { 
     $this->belongsTo('Orders'); 
    } 

    public function addresses() 
    { 
     $this->hasMany('Customeraddress', 'id', 'customer_id'); 
    } 

    public function scopeGetBillingAddress($query, $addressId) 
    { 
     return $this->addresses() 
        ->where('id', '=', $addressId) 
        ->where('type', '=', 'billing'); 
    } 

    public function scopeGetShippingAddress($query, $addressId) 
    { 
     return $this->addresses() 
        ->where('id', '=', $addressId) 
        ->where('type', '=', 'shipping'); 
    } 
} 

最後這裏是我的customeraddress型號：

class Customeraddress extends Eloquent 
{ 
    protected $table = "customer_addresses"; 
    protected $softDelete = true; 

    public function customer() 
    { 
     $this->belongsTo('Customer'); 
    } 
} 

現在，我想我的控制器上運行該工具來獲取訂單地址，但我不斷收到錯誤。我如何能夠通過雄辯的關係和範圍功能來做到這一點？

$address = Orders::find(21)->billingAddress()->first(); 
echo $address->street; 

Answer 1

變化這一個：

public function addresses() 
{ 
    // $this->hasMany('Customeraddress', 'id', 'customer_id'); // wrong order of keys 
    return $this->hasMany('Customeraddress', 'customer_id', 'id'); 
} 

這兩個

// edit: Order is a child of customer and client so: 
public function customer() 
{ 
    //return $this->hasOne('Customer', 'customer_id', 'id'); 
    return $this->belongsTo('Customer', 'customer_id', 'id'); // customer_id and id are redundant bu I leave it for clarity 
} 

public function client() 
{ 
    //return $this->hasOne('Client', 'client_id', 'id'); 
    return $this->belongsTo('Client', 'client_id', 'id'); // same here 
} 

順便說一下，這個人是危險的:)

public function billingAddress() 
{ 
    // This line results in db query everytime you call billingAddress 
    // Unless you cache the query, it's overkill 
    if($this->client()->first() != null) 

    // instead use: 
    if($this->client != null) 

    { 
     return $this->client()->getBillingAddress($this->billing_address_id); 
    } 
    else 
    { 
     return $this->customer()->getBillingAddress($this->billing_address_id); 
    } 
} 

變化範圍來存取：

public function getBillingAddressAttribute($addressId) 
{ 
    return $this->addresses() 
       ->where('id', '=', $addressId) 
       ->where('type', '=', 'billing')->first(); 
} 

public function getShippingAddressAttribute($addressId) 
{ 
    return $this->addresses() 
       ->where('id', '=', $addressId) 
       ->where('type', '=', 'shipping')->first(); 
} 

// then you can call it like $customer->shippingAddress etc