nhooyr.io/websocket 前端发送消息报错 failed to read JSON message: failed to unmarshal JSON: invalid ch

## 问题描述 使用 nhooyr.io/websocket 起了websocket 服务 前端使用 ws.send 发送消息 ``` js ws.onopen = function () { // Web Socket 已连接上，使用 send() 方法发送数据 ws.send('msg'); }; ``` websocket 服务会报错 ## 报错内容 ``` shell 2021/04/29 14:41:11 read from client error: failed to read JSON message: failed to unmarshal JSON: invalid character 'xxx' looking for beginning of value ``` ## 解决办法 原因在于 nhooyr.io/websocket 的 wsjson.Read 只能接受 json 格式的字符串 源码 ```go // Read reads a JSON message from c into v. // It will reuse buffers in between calls to avoid allocations. func Read(ctx context.Context, c *websocket.Conn, v interface{}) error { return read(ctx, c, v) } func read(ctx context.Context, c *websocket.Conn, v interface{}) (err error) { defer errd.Wrap(&err, "failed to read JSON message") _, r, err := c.Reader(ctx) if err != nil { return err } b := bpool.Get() defer bpool.Put(b) _, err = b.ReadFrom(r) if err != nil { return err } err = json.Unmarshal(b.Bytes(), v) if err != nil { c.Close(websocket.StatusInvalidFramePayloadData, "failed to unmarshal JSON") return fmt.Errorf("failed to unmarshal JSON: %w", err) } return nil } ``` 前端改成json格式发送 ```js ws.onopen = function () { let msg = JSON.stringify({ "content": "连接成功" }); ws.send(msg); }; ```