如何在typescript中通过ssdp发送http请求

Question

我正在学习本教程：https://sdkdocs.roku.com/display/sdkdoc/External+Control+API ...trying，通过ssdp / http get获取设备列表。

​

        let query: string = "M-SEARCH * HTTP/1.1\r\n" +
            "HOST: 239.255.255.250:1900\r\n" +
            "MAN: \"ssdp:discover\"\r\n" +
            "ST: roku: ecp\r\n\r\n";

        this.http
            .get(query)
            .map(res => res.json())
            .subscribe(
            (data) => this.devices = data,
            (err) => this.error = err);

​

..。但我得到了一个404错误(而且，localhost正被附加到字符串)：

Failed to load resource: the server responded with a status of 404 (Not Found)

​

​

http://localhost:52125/M-SEARCH%20*%20HTTP/1.1HOST:%20239.255.255.250:1900MAN:%20%22ssdp:discover%22ST:%20roku:%20ecp

​

Answer 1

SSDP使用HTTPU或UDP上的HTTP。节点的HTTP客户端仅通过TCP发送数据。您将需要使用udp套接字手动发送此消息并侦听数据，或者使用预先存在的库，如node-ssdp。