For Actionhero v21.x.x

Why Typescript?

Actionhero is moving to Typescript.

Typescript is a language that compiles to javascript that makes the developer experience much nicer. It includes features like type checking, sharing interfaces and modules, and generally other "quality of life" features found in other languages to help you write better javascript code.

For Actionhero, that means we can now provide:

Type Hinting

Module definitions

Automatic Documentation directly from the code

Visit docs.actionherojs.com to see this live!

...and an overall more pleasant developer experience!

Note: You do not have to use Typescript to use Actionhero! Other than some layout changes to your project, you can continue to use Actionhero with regular javascript node.js projects. We will always ship compiled javascript files to NPM so that actionhero will still work with the most recent versions of Node.js. That said, the generators will favor Typescript projects moving forward, creating Typescript files

Actionhero will create and install everything you need for a pleasant typescript experience, including a tsconfig file, node's @types and development tools already linked into your package.json

Upgrading Packages & Package.json

If you are upgrading an existing Actionhero project, the first thing to do is install the related packages and create new files:

npm install --save actionhero@next
npm install --save-dev @types/node prettier
npm uninstall standard

Update your scripts in package.json

"scripts": {
  "dev": "ts-node-dev --transpile-only src/server.ts",
  "start": "node dist/server.js",
  "actionhero": "actionhero",
  "test": "jest",
  "pretest": "npm run build && npm run lint",
  "postinstall": "npm run build",
  "build": "tsc --declaration",
  "lint": "prettier --check src/*/** __test__/*/**",
  "pretty": "prettier --write src/*/** __test__/*/**"

and your jest config as well, also in package.json

"jest": {
  "testEnvironment": "node",
  "transform": {
    "^.+\\.ts?$": "ts-jest"

Remove the block about standard from your package.json. We are switching to prettier because it has better typescript support.

Remember - you will be using npm run dev now when developing locally.

Typescript Configuration

Typescript is managed by a tsconfig.json file at the root of your project. Create one now with the following content:

  "compilerOptions": {
    "outDir": "./dist",
    "allowJs": true,
    "module": "commonjs",
    "target": "es2018"
  "include": ["./src/**/*"]

Project Structure

  1. Create the src and dist directories
  2. Move Actions, Tasks, Initializers, Servers, and Config into src
  3. Create a new modules directory

Your project should now look like this:

|- src
|  - server.ts
|  - config
|    - (project settings)
|  - actions
|    -- (your actions)
|  - initializers
|    -- (any additional initializers you want)
|  - servers
|    -- (custom servers you may make)
|  - tasks
|    -- (your tasks)
|  - bin
|    -- (your custom CLI commands)
|- locales
|-- (translation files)
|- __tests__
|-- (tests for your API)
| - log
|-- (default location for logs)
|- node_modules
|-- (your modules, actionhero should be npm installed in here)
|- pids
|-- (pidfiles for your running servers)
|- public
|-- (your static assets to be served by /file)

Create server.ts

Create server.ts at /src/server.ts

import { Process } from "actionhero";

// load any custom code, configure the env, as needed

async function main() {
  // create a new actionhero process
  const app = new Process();

  // handle unix signals and uncaught exceptions & rejections

  // start the app!
  // you can pass custom configuration to the process as needed
  await app.start();


Update JS to TS syntax

Typescript uses the latest ES6-style syntax for importing and exporting things. You do not need to use babel to get this to work... Typescript does it for you!

  • Rename all the files you just moved into src from *.js to *.ts files
    • A Helpful rename command for unix/osx computers to do this is -> for f in _.js; do mv -- "$f" "${f%.js}.ts"; done
  • Change the imports from Require-style const {thing} = require('thing') to Import-style import { thing } from 'thing'
  • Change all the exports from Module-style module.exports = ... or exports.thing = ... to ES6-style export const thing = ...

For example:


const { Action } = require("actionhero");

exports.default = class MyAction extends Action {
  constructor() {
    this.name = "hello";
    this.description = "an actionhero action";
    this.outputExample = { message: "hello" };

  async run() {
    return { message: "hello" };


import { Action } from "actionhero";

export class MyAction extends Action {
  constructor() {
    this.name = "hello";
    this.description = "an actionhero action";
    this.outputExample = { message: "hello" };

  async run() {
    response.message = "hello";


The config module (it is a module now!) produces a static object with your configuration. This means that it can be required via import {config} from 'actionhero' at any point in your project's life cycle... you no longer need to wait for the initialization process to complete. However, this required some changes:

  • The config methods no longer provide api, they provide config. Only other information from other config files is available to you, nothing from the rest of the application.

To upgrade your config:

  • Change all of the exports, per above. When exporting the default config, use DEFAULT (all caps), ie: export const DEFAULT = {config: { ... }}
  • Update your paths in config/general , ie:
paths: {
  action: [path.join(__dirname, "..", "actions")],
  task: [path.join(__dirname, "..", "tasks")],
  server: [path.join(__dirname, "..", "servers")],
  cli: [path.join(__dirname, "..", "bin")],
  initializer: [path.join(__dirname, "..", "initializers")],
  public: [path.join(process.cwd(), "public")],
  pid: [path.join(process.cwd(), "pids")],
  log: [path.join(process.cwd(), "log")],
  plugin: [path.join(process.cwd(), "node_modules")],
  locale: [path.join(process.cwd(), "locales")],
  test: [path.join(process.cwd(), "__tests__")],
  src: path.join(process.cwd(), "src"),
  dist: path.join(process.cwd(), "dist")

Don’t forget any paths you might have in other environments (like test)!

Middleware and Sessions

Now with Typescript, you’ll get an error if you try to set arbitrary properties on the data object either within an Action or Middleware. We need a place to pass data from the middleware to the action.

// in an initializer
import { action } from "actionhero";
import { models } from "./../models"; // in your project

const authenticatedTeamMemberMiddleware = {
  name: "authenticated-team-member",
  global: false,
  priority: 1000,
  preProcessor: async (data) => {
    const { Team, TeamMember } = models;
    const sessionData = await api.session.load(data.connection);
    if (!sessionData) {
      throw new Error("Please log in to continue");
    } else if (
      !data.params.csrfToken ||
      data.params.csrfToken !== sessionData.csrfToken
    ) {
      throw new Error("CSRF error");
    } else {
      const teamMember = await TeamMember.findOne({
        where: { guid: sessionData.guid },
        include: Team,
      data.session.data = sessionData; /// <--- HERE/
      data.session.teamMember = teamMember; /// <--- HERE/


Modules and Initializers

A number of things have been moved out of the API object to simplify their use by creating import/export modules you can require directly. In this way, you can get type hinting for various parts of Actionhero! This is a logical separation between initializers - code that executes when your server boots up and loads or connects vs modules which provide an API for you to use in your code.

For example, the task system has been split into 2 parts - both a module and initializer. The initializer continues to load your tasks into api.tasks.tasks, but doesn’t expose any methods for you to use. Now, when you want to enqueue a task, you call task.enqueue() you load it from the module via import {task} from 'actionhero'

The initialize, start, and stop methods of your initializers will now be passed config. This is helpful in the off chance you are modifying config and cannot rely on the static export of that information (this is rare).

Removed from the API object and are now directly exported by Actionhero as modules:

ie: import { log, config } from 'actionhero'

  • log (the method to write to the logs)
  • config (the config object hash)
  • action (addMiddleware)
  • task (addMiddleware)
  • cache
  • task
  • i18n
  • specHelper
  • id (the server’s id)
  • env (development, staging, production)
  • localize (method that accepts a string and a connection)

The API object

what remains on the API object are truly things about your API - actions, tasks, servers, initializers. And now these elements are very typesafe. You can no longer add and remove things randomly to the API object. This means that in your project, you should create imports and exports directly and share them with your actions and tasks.


A polyfill will be included in the first few releases of Actionhero in typescript to port the new exports back to the api object. A warning will be displayed.

A new config setting to enable or disable the polyfill is located at config.general.legacyApiPolyfill


  • config.general.id: can no longer be set
  • config.i18n.determineConnectionLocale: this method should be set on the i18n object exported by Actionhero.


  • chatRoom.sanitizeMemberDetails() is no longer overrideable/customizable.


We have removed the custom module loaders for Actionhero's development mode, watchFileAndAct. Now that we need to transpile our applications from typescript to javascript, we can rely on some of the excellent packages already developed for this purpose. Newly generated Actionhero projects will make use of node-ts-dev (https://github.com/whitecolor/ts-node-dev) to boot and reload your projects when running in typescript mode.

Javascript projects can do a similar thing via the nodemon (https://nodemon.io/) package


    Actionhero was built from the ground up to include all the features you expect from a modern API framework.

    Open Source

    The Actionhero server is open source, under the Apache-2 license

    Actionhero runs on Linux, OS X, and Windows

    You always have access to the Actionhero team via Slack and Github

    Premium Training & Review

    We provide support for corporate & nonprofit customers starting at a flat rate of $150/hr. Our services include:

    • Remote training for your team
    • Code Reviews
    • Best Practices Audits
    • Custom plugin & Feature Development

    We have packages appropriate for all company sizes. Contact us to learn more.

    Premium Training & Review

    We provide support for corporate & nonprofit customers starting at a flat rate of $150/hr. Our services include:

    • Remote training for your team
    • Code Reviews
    • Best Practices Workshops
    • Custom plugin & Feature Development

    We have packages appropriate for all company sizes. Contact us to learn more.


    For larger customers in need of a support contract, we offer an enterprise plan including everything in the Premium plan plus:

    • 24/7 access to core members of the Actionhero Team
    • Emergency response packages
    • Deployment support
    • ...and custom development against Actionhero’s core as needed.