增加http代理功能 (#2988)

支持通过http代理拉流, 避免内外网复杂网络环境时需要专门配置防火墙,现在只需要配置一台代理内网的服务器.

---------

Co-authored-by: xia-chu <771730766@qq.com>

src/Http/HttpClient.h

@@ -141,6 +141,11 @@ public:
      */
     void setCompleteTimeout(size_t timeout_ms);
 
+    /**
+     * 设置http代理url
+     */
+    void setProxyUrl(std::string proxy_url);
+
 protected:
     /**
      * 收到http回复头
@@ -181,11 +186,16 @@ protected:
     void onFlush() override;
     void onManager() override;
 
+    void clearResponse();
+
+    bool checkProxyConnected(const char *data, size_t len);
+    bool isUsedProxy() const;
+    bool isProxyConnected() const;
+
 private:
     void onResponseCompleted_l(const toolkit::SockException &ex);
     void onConnect_l(const toolkit::SockException &ex);
     void checkCookie(HttpHeader &headers);
-    void clearResponse();
 
 private:
     //for http response
@@ -215,6 +225,13 @@ private:
     toolkit::Ticker _wait_header;
     toolkit::Ticker _wait_body;
     toolkit::Ticker _wait_complete;
+
+    bool _used_proxy = false;
+    bool _proxy_connected = false;
+    uint16_t _proxy_port;
+    std::string _proxy_url;
+    std::string _proxy_host;
+    std::string _proxy_auth;
 };
 
 } /* namespace mediakit */