Deploying to Google App Engine with Typescript/Node

A guide to get you up and running on the Google App Engine using Typescript targetting Node.

Table of Contents

• Deploying to Google App Engine with Typescript/Node
  • Table of Contents
  • Lexicon
  • Prerequisites
  • Steps to MVP
    • Create an app.yaml
    • Create a Typescript Project
    • Customize the tsconfig.json
    • Install Some Project Dependencies
      • Dependencies
      • Dev Dependencies
    • Add NPM Scripts
    • Add Some Code
    • Add .gcloudignore
    • Deploy

Lexicon

• .gcloudignore: files to ignore when uploading to Google Cloud. Uses the same syntax as .gitignore.
• gcloud: CLI interface for Google Cloud, can be obtained here.
• app.yaml: Configuration for your Google Cloud App Engine app. Reference here.
• gcp-build: Special node script that Google Cloud runs before it calls npm start.

Prerequisites

• Cloud SDK CLI tool installed (gcloud)
• Node installed (10.x+ for this repo)

Steps to MVP

To deploy to Google App Engine with your Typescript project, use the following steps:

Create an app.yaml

The app.yaml contains some infrastructure information for your deployment. You may use something like this:

runtime: nodejs10
instance_class: F1
automatic_scaling:
  max_instances: 1

Note: as of writing, the only node runtimes supported are nodejs10 and nodejs8.

The settings I have chosen keep me within free tier. You may customize it to your liking.

Create a Typescript Project

Create the inital tsconfig.json to get started with Typescript:

tsc --init

Customize the tsconfig.json

We should make a couple modifications to the tsconfig.json. We will want to specify the directory where our code will lie using the rootDir field, and we need to specify a directory to output js files to using outDir. You may output js beside the ts files by not specifying anything, but that gets a little too messy.

Install Some Project Dependencies

Dependencies

npm i express

Dev Dependencies

npm i -D typescript @types/express

Add NPM Scripts

Your package.json should at minimum have these scripts:

"scripts": {
    "start": "node ./dist/index.js",
    "gcp-build": "tsc -p ."
  }

Google Cloud will run your gcp-build script if specified, and use npm start to run your application. Use gcp-build to run your Typescript compiler, or use your own build script. npm start must be able to get into the index.js created by tsc.

Add Some Code

Make a src directory:

mkdir src

Then add some basic server code:

// src/index.ts

import express = require('express');

const port = Number(process.env.PORT) || 8080;

const app = express();
app.enable('trust proxy');


const server = app.use('/', (req, res, next) => {
    res.status(200).send('Hello Google App Engine');
}).listen(port);

Add .gcloudignore

Ignore files you don't want to upload to Google Cloud:

.gcloudignore
.git
.gitignore
node_modules/
scripts
dist

Deploy

You may deploy your app to the Google App Engine using the following:

gcloud app deploy

Note: For this to work, you had to have gone through the process of installing the Cloud SDK CLI. Instructions for setting up the Cloud SDK can be found here.