Update: README

Author: Openset

README.md

@@ -1,2 +1,68 @@
-# http
+## http
 Http request for php
+
+### Requirement
+
+1. PHP >= 5.6
+2. **[Composer](https://getcomposer.org/)**
+
+## Installation
+
+```shell
+$ composer require openset/http
+```
+
+### Usage
+
+```php
+<?php
+
+use Openset\HttpClient;
+
+// 修改默认配置（可选）
+HttpClient::setConfig(['debug' => false, 'verify' => true]);
+
+// 发送get请求
+$resp = HttpClient::get('https://www.example.com/');
+
+// Response对象实现了一个PSR-7接口 Psr\Http\Message\ResponseInterface ， 包含了很多有用的信息。
+
+// 你可以获取这个响应的状态码和和原因短语(reason phrase)：
+
+$code = $resp->getStatusCode(); // 200
+$reason = $resp->getReasonPhrase(); // OK
+// 你可以从响应获取头信息(header)：
+
+// Check if a header exists.
+if ($response->hasHeader('Content-Length')) {
+    echo "It exists";
+}
+
+// Get a header from the response.
+echo $response->getHeader('Content-Length');
+
+// Get all of the response headers.
+foreach ($response->getHeaders() as $name => $values) {
+    echo $name . ': ' . implode(', ', $values) . "\r\n";
+}
+// 使用 getBody 方法可以获取响应的主体部分(body)，主体可以当成一个字符串或流对象使用
+
+$body = $resp->getBody();
+// Implicitly cast the body to a string and echo it
+echo $body;
+// Explicitly cast the body to a string
+$stringBody = (string) $body;
+// Read 10 bytes from the body
+$tenBytes = $body->read(10);
+// Read the remaining contents of the body as a string
+$remainingBytes = $body->getContents();
+
+```
+
+## Contributors
+
+[Your contributions are always welcome!](https://github.com/openset/http/graphs/contributors)
+
+## LICENSE
+
+Released under [MIT](https://github.com/openset/http/blob/master/LICENSE) LICENSE