PSaaS Appliance: Webtasks

Beginning with Build 7247, you may use the PSaaS Appliance's version of Webtasks to execute your rules and custom database logic.


Prior to working with Webtasks, please ensure that you have configured the:


Auth0 provides different stages (which are known as sandboxes) on which you may run your rules and custom database logic:

  • node_sandbox (default): while more secure than eval, node_sandbox is more resource intensive;
  • eval: provides the best performance, but is the least secure of the three available modes;
  • auth0-sandbox: provides better performance that node_sandbox, improved isolation over eval, and offers a greater number of Node.js modules for use with your custom code.

Only one sandbox mode may be selected at any given time (for example, you may not run selected rules in one sandbox and other rules in another sandbox). If you would like to change the sandbox mode, please discuss this with your Auth0 Customer Success Engineer.

Code Compatibility

Code that you have written for use with node-sandbox or eval will work in auth0-sandbox. However, code that is written for auth0-sandbox may not be compatible with node-sandbox or eval, especially if your code uses modules.

The auth0-sandbox is the recommended method for running your custom code.

Working with Webtasks

You may use Webtasks by calling its endpoints directly. This can be done using the Webtask Command Line Interface (wt-cli) and specifying the --url "https://webtask.<a0url>.com" parameter (where a0url is the address of the PSaaS Appliance node). For additional information on setting up the wt-cli, please see Getting Started with Webtasks.

Node.js Modules

Currently, not all of the Node.js modules available for the Auth0 Cloud Environment are available for the PSaaS Appliance.

To see which modules are available for Webtasks running on PSaaS Appliance instances, execute the List Modules Webtask using the appropriate sandbox on your PSaaS Appliance instance.

First, copy locally the List Modules Webtask, either by downloading the file or by copying this code:

'use npm';
const Fs = require('fs');
const Verquire = require('verquire');
const _ = require('lodash@4.8.2');

const abcsort = function (a, b) {
  if ( < {
      return -1;

  if ( > {
      return 1;

  return 0;

const natives = Object.keys(process.binding("natives"))
    .filter(nativeDep => nativeDep[0] !== '_')
    .map(dep => ({name: dep, version: 'native'}))

const modules = _.flatMap(Verquire.modules, (versions, module_name) => {
   return => {
       const moduleObj = {
         name: module_name,
         version: version

       return moduleObj;

module.exports = cb => {
    cb(null, {
        node_version: process.version,
        modules: natives.concat(modules)

Afterwards, create a webtask profile using wt-cli, if you don't already have one.

wt init --container "YOUR_TENANT_NAME" --url "WEBTASK_URL" --token "eyJhbGci..." -p "a``YOUR_TENANT_NAME-default"

Now you are ready to register your webtask, using the wt create command. This command receives as input a path or URL of the webtask's code and provides as output the URL where the webtask is available.

If you saved the file under a my-webtasks directory as list_modules.js you would use the following:

wt create ./my-webtasks/list_modules.js

You should get a message that the webtask was created, alongside with the URL to access it. The response is a JSON object.


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