提供本地文件
问题
您希望创建一个 HTTP 端点，该端点响应 GET 请求，并提供来自本地文件的内容，例如 PNG 图像。
解决方案
使用 File In 节点加载所需内容，并将 Content-Type 设置为与返回文件类型相应的适当值。
示例
[{"id":"c7e341a0.381cc","type":"http in","z":"3045204d.cfbae","name":"","url":"/hello-file","method":"get","swaggerDoc":"","x":110,"y":720,"wires":[["2fb1c354.d04e3c"]]},{"id":"2fb1c354.d04e3c","type":"file in","z":"3045204d.cfbae","name":"","filename":"/tmp/node-red.png","format":"","x":290,"y":720,"wires":[["c9e28681.361d78"]]},{"id":"c9e28681.361d78","type":"change","z":"3045204d.cfbae","name":"Set Headers","rules":[{"t":"set","p":"headers","pt":"msg","to":"{}","tot":"json"},{"t":"set","p":"headers.content-type","pt":"msg","to":"image/png","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":470,"y":720,"wires":[["88974243.7768c"]]},{"id":"88974243.7768c","type":"http response","z":"3045204d.cfbae","name":"","x":610,"y":720,"wires":[]}]
[~]$ curl https://:1880/hello-file > file.png
讨论
加载非文本文件（如图像）时，必须将 File In 节点配置为返回 Buffer 对象。
为了让接收方知道如何处理文件，Content-Type 标头必须设置为相应的 MIME 类型。上面的示例返回一个 .png 文件，它将 Content-Type 标头设置为 image/png。
