2.请求头
### 请求头
|参数名|描述|
|-|-|-|
|Content-Type|内容类型|
|appKey|授权Key|
|signature|签名值|
|timestamp|时间戳|
### 示例
<table>
<tr>
<td>Content-Type</td>
<td>application/json</td>
</tr>
<tr>
<td>appKey</td>
<td>testOnlyAppKey</td>
</tr>
<tr>
<td>signature</td>
<td>89037df84706b6e4eb58fde9d8f0cf94560b438</td>
</tr>
<tr>
<td>timestamp</td>
<td>1635478320000</td>
</tr>
</table>