I'm using PDF.JS for loading pdfs. While loading pdf, i'm getting this error,

ERROR Error: Unknown action from worker: undefined
    at Worker.MessageHandler._onComObjOnMessage (pdf.js:6846)
    at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (zone.js:421)
    at Object.onInvokeTask (core.js:28122)
    at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (zone.js:420)
    at Zone.push../node_modules/zone.js/dist/zone.js.Zone.runTask (zone.js:188)
    at ZoneTask.push../node_modules/zone.js/dist/zone.js.ZoneTask.invokeTask [as invoke] (zone.js:503)
    at invokeTask (zone.js:1671)
    at Worker.globalZoneAwareCallback (zone.js:1697)

undefined es from actionHandler

In pdf.js:6846

 const action = this.actionHandler[data.action];

      if (!action) {
        throw new Error(`Unknown action from worker: ${data.action}`);
      }

I took reference from here, ponent.ts

I'm using the worker from .worker.min.js

pdfjsLib.GlobalWorkerOptions.workerSrc = 'assets/js/pdf.worker.min.js';

I'm using PDF.JS for loading pdfs. While loading pdf, i'm getting this error,

ERROR Error: Unknown action from worker: undefined
    at Worker.MessageHandler._onComObjOnMessage (pdf.js:6846)
    at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (zone.js:421)
    at Object.onInvokeTask (core.js:28122)
    at ZoneDelegate.push../node_modules/zone.js/dist/zone.js.ZoneDelegate.invokeTask (zone.js:420)
    at Zone.push../node_modules/zone.js/dist/zone.js.Zone.runTask (zone.js:188)
    at ZoneTask.push../node_modules/zone.js/dist/zone.js.ZoneTask.invokeTask [as invoke] (zone.js:503)
    at invokeTask (zone.js:1671)
    at Worker.globalZoneAwareCallback (zone.js:1697)

undefined es from actionHandler

In pdf.js:6846

 const action = this.actionHandler[data.action];

      if (!action) {
        throw new Error(`Unknown action from worker: ${data.action}`);
      }

I took reference from here, https://github./jzgoda/ng-pdfjs/blob/master/src/app/app.ponent.ts

I'm using the worker from https://github./jzgoda/ng-pdfjs/blob/master/src/assets/pdf.worker.min.js

pdfjsLib.GlobalWorkerOptions.workerSrc = 'assets/js/pdf.worker.min.js';

• javascript
• pdf.js

1 Answer 1

i got this same error before:

ERROR Error: Unknown action from worker: undefined

and my code is

var pdfjsLib = require("pdfjs-dist/build/pdf.js");
pdfjsLib.GlobalWorkerOptions.workerSrc = 'assets/js/pdf.worker.min.js';

The code does not a problem. My work as upgrading the pdf.js to latest version. During my own operation error, i copied the different version of pdf.js and pdf.worker.min.js, then came out above error. After i prepared a matching version between pdf.js and pdf.worker.min.js. Then this error disappears. This is for your reference.