Implement http based callback

bin/utils.js

@@ -7,6 +7,14 @@ const decoding = require('lib0/dist/decoding.cjs')
 const mutex = require('lib0/dist/mutex.cjs')
 const map = require('lib0/dist/map.cjs')
 
+const debounce = require('lodash.debounce')
+
+const callbackHandler = require('./callback.js').callbackHandler
+const isCallbackSet = require('./callback.js').isCallbackSet
+
+const CALLBACK_DEBOUNCE_WAIT = process.env.CALLBACK_DEBOUNCE_WAIT || 2000
+const CALLBACK_DEBOUNCE_MAXWAIT = process.env.CALLBACK_DEBOUNCE_MAXWAIT || 10000
+
 const wsReadyStateConnecting = 0
 const wsReadyStateOpen = 1
 const wsReadyStateClosing = 2 // eslint-disable-line
@@ -110,6 +118,13 @@ class WSSharedDoc extends Y.Doc {
     }
     this.awareness.on('update', awarenessChangeHandler)
     this.on('update', updateHandler)
+    if (isCallbackSet()) {
+      this.on('update', debounce(
+        callbackHandler,
+        CALLBACK_DEBOUNCE_WAIT,
+        { maxWait: CALLBACK_DEBOUNCE_MAXWAIT }
+      ))
+    }
   }
 }