feat: add onError cb (cudr#15)

Author: cudr

README.md

@@ -30,6 +30,7 @@ Check [detailed example](https://github.com/cudr/slate-collaborative/blob/master
   cursorData?: any // any data passed to cursor
   onConnect?: () => void // connect callback
   onDisconnect?: () => void // disconnect callback
+  onError?: (reason: string) => void // error callback
 }
 ```
 

packages/client/src/withSocketIO.ts

@@ -11,6 +11,8 @@ export interface SocketIOPluginOptions {
 
   onConnect?: () => void
   onDisconnect?: () => void
+
+  onError?: (msg: string) => void
 }
 
 export interface WithSocketIOEditor {
@@ -35,7 +37,14 @@ const withSocketIO = <T extends AutomergeEditor>(
 ) => {
   const e = editor as T & WithSocketIOEditor
 
-  const { onConnect, onDisconnect, connectOpts, url, autoConnect } = options
+  const {
+    onConnect,
+    onDisconnect,
+    onError,
+    connectOpts,
+    url,
+    autoConnect
+  } = options
 
   /**
    * Connect to Socket.
@@ -54,6 +63,10 @@ const withSocketIO = <T extends AutomergeEditor>(
       })
     }
 
+    e.socket.on('error', (msg: string) => {
+      onError && onError(msg)
+    })
+
     e.socket.on('msg', (data: CollabAction) => {
       e.receive(data)
     })