You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
151 lines
4.7 KiB
151 lines
4.7 KiB
10 years ago
|
响应格式
|
||
|
===================
|
||
|
|
||
|
当处理一个 RESTful API 请求时, 一个应用程序通常需要如下步骤
|
||
|
来处理响应格式:
|
||
|
|
||
|
1. 确定可能影响响应格式的各种因素, 例如媒介类型, 语言, 版本, 等等。
|
||
|
这个过程也被称为 [content negotiation](http://en.wikipedia.org/wiki/Content_negotiation)。
|
||
|
2. 资源对象转换为数组, 如在 [Resources](rest-resources.md) 部分中所描述的。
|
||
|
通过 [[yii\rest\Serializer]] 来完成。
|
||
|
3. 通过内容协商步骤将数组转换成字符串。
|
||
|
[yii\web\ResponseFormatterInterface|response formatters]] 通过
|
||
|
[yii\web\Response::formatters|response]] 应用程序组件来注册完成。
|
||
|
|
||
|
|
||
|
## 内容协商 <a name="content-negotiation"></a>
|
||
|
|
||
|
Yii 提供了通过 [[yii\filters\ContentNegotiator]] 过滤器支持内容协商。RESTful API 基于
|
||
|
控制器类 [[yii\rest\Controller]] 在 `contentNegotiator` 下配备这个过滤器。
|
||
|
文件管理器提供了涉及的响应格式和语言。 例如, 如果一个 RESTful
|
||
|
API 请求中包含以下 header,
|
||
|
|
||
|
```
|
||
|
Accept: application/json; q=1.0, */*; q=0.1
|
||
|
```
|
||
|
|
||
|
将会得到JSON格式的响应,如下:
|
||
|
|
||
|
```
|
||
|
$ curl -i -H "Accept: application/json; q=1.0, */*; q=0.1" "http://localhost/users"
|
||
|
|
||
|
HTTP/1.1 200 OK
|
||
|
Date: Sun, 02 Mar 2014 05:31:43 GMT
|
||
|
Server: Apache/2.2.26 (Unix) DAV/2 PHP/5.4.20 mod_ssl/2.2.26 OpenSSL/0.9.8y
|
||
|
X-Powered-By: PHP/5.4.20
|
||
|
X-Pagination-Total-Count: 1000
|
||
|
X-Pagination-Page-Count: 50
|
||
|
X-Pagination-Current-Page: 1
|
||
|
X-Pagination-Per-Page: 20
|
||
|
Link: <http://localhost/users?page=1>; rel=self,
|
||
|
<http://localhost/users?page=2>; rel=next,
|
||
|
<http://localhost/users?page=50>; rel=last
|
||
|
Transfer-Encoding: chunked
|
||
|
Content-Type: application/json; charset=UTF-8
|
||
|
|
||
|
[
|
||
|
{
|
||
|
"id": 1,
|
||
|
...
|
||
|
},
|
||
|
{
|
||
|
"id": 2,
|
||
|
...
|
||
|
},
|
||
|
...
|
||
|
]
|
||
|
```
|
||
|
|
||
|
幕后,执行一个 RESTful API 控制器动作之前,[[yii\filters\ContentNegotiator]]
|
||
|
filter 将检查 `Accept` HTTP header 在请求时和配置 [[yii\web\Response::format|response format]]
|
||
|
为 `'json'`。 之后的动作被执行并返回得到的资源对象或集合,
|
||
|
[[yii\rest\Serializer]] 将结果转换成一个数组。最后,[[yii\web\JsonResponseFormatter]]
|
||
|
该数组将序列化为JSON字符串,并将其包括在响应主体。
|
||
|
|
||
|
默认, RESTful APIs 同时支持JSON和XML格式。为了支持新的格式,你应该
|
||
|
在 `contentNegotiator` 过滤器中配置 [[yii\filters\ContentNegotiator::formats|formats]] 属性,
|
||
|
类似如下 API 控制器类:
|
||
|
|
||
|
```php
|
||
|
use yii\web\Response;
|
||
|
|
||
|
public function behaviors()
|
||
|
{
|
||
|
$behaviors = parent::behaviors();
|
||
|
$behaviors['contentNegotiator']['formats']['text/html'] = Response::FORMAT_HTML;
|
||
|
return $behaviors;
|
||
|
}
|
||
|
```
|
||
|
|
||
|
`formats` 属性的keys支持 MIME 类型,而 values 必须在 [[yii\web\Response::formatters]]
|
||
|
中支持被响应格式名称。
|
||
|
|
||
|
|
||
|
## 数据序列化 <a name="data-serializing"></a>
|
||
|
|
||
|
正如我们上面所描述的,[[yii\rest\Serializer]] 负责转换资源的中间件
|
||
|
对象或集合到数组。它将对象 [[yii\base\ArrayableInterface]] 作为
|
||
|
[[yii\data\DataProviderInterface]]。 前者主要由资源对象实现, 而
|
||
|
后者是资源集合。
|
||
|
|
||
|
你可以通过设置 [[yii\rest\Controller::serializer]] 属性和一个配置数组。
|
||
|
例如,有时你可能想通过直接在响应主体内包含分页信息来
|
||
|
简化客户端的开发工作。这样做,按照如下规则配置 [[yii\rest\Serializer::collectionEnvelope]]
|
||
|
属性:
|
||
|
|
||
|
```php
|
||
|
use yii\rest\ActiveController;
|
||
|
|
||
|
class UserController extends ActiveController
|
||
|
{
|
||
|
public $modelClass = 'app\models\User';
|
||
|
public $serializer = [
|
||
|
'class' => 'yii\rest\Serializer',
|
||
|
'collectionEnvelope' => 'items',
|
||
|
];
|
||
|
}
|
||
|
```
|
||
|
|
||
|
那么你的请求可能会得到的响应如下 `http://localhost/users`:
|
||
|
|
||
|
```
|
||
|
HTTP/1.1 200 OK
|
||
|
Date: Sun, 02 Mar 2014 05:31:43 GMT
|
||
|
Server: Apache/2.2.26 (Unix) DAV/2 PHP/5.4.20 mod_ssl/2.2.26 OpenSSL/0.9.8y
|
||
|
X-Powered-By: PHP/5.4.20
|
||
|
X-Pagination-Total-Count: 1000
|
||
|
X-Pagination-Page-Count: 50
|
||
|
X-Pagination-Current-Page: 1
|
||
|
X-Pagination-Per-Page: 20
|
||
|
Link: <http://localhost/users?page=1>; rel=self,
|
||
|
<http://localhost/users?page=2>; rel=next,
|
||
|
<http://localhost/users?page=50>; rel=last
|
||
|
Transfer-Encoding: chunked
|
||
|
Content-Type: application/json; charset=UTF-8
|
||
|
|
||
|
{
|
||
|
"items": [
|
||
|
{
|
||
|
"id": 1,
|
||
|
...
|
||
|
},
|
||
|
{
|
||
|
"id": 2,
|
||
|
...
|
||
|
},
|
||
|
...
|
||
|
],
|
||
|
"_links": {
|
||
|
"self": "http://localhost/users?page=1",
|
||
|
"next": "http://localhost/users?page=2",
|
||
|
"last": "http://localhost/users?page=50"
|
||
|
},
|
||
|
"_meta": {
|
||
|
"totalCount": 1000,
|
||
|
"pageCount": 50,
|
||
|
"currentPage": 1,
|
||
|
"perPage": 20
|
||
|
}
|
||
|
}
|
||
|
```
|