How to Deploy Koa Applications to GCP with Nanobox

Koa is a new web framework, built on Node.js, and designed by the team behind Express, which aims to be a smaller, more expressive, and more robust foundation for web applications and APIs. Google Cloud Platform (GCP) is a robust collection of cloud-based tools and services covering everything from Infrastructure as a Service (IaaS) to machine learning and security.

In this article, I'm going to walk through deploying a Koa application to GCP using Nanobox. Nanobox uses Docker to build local development and staging environments, as well as scalable, highly-available production environments on GCP.

Before You Begin

If you haven't already, create a free Nanobox account and download Nanobox Desktop.

Setup A Koa Project

Prerequisite: This guide assumes you already have Node and NPM installed. If not, you can quickly install Node (which includes NPM) and return.

Where to start:

Starting From Scratch

From the directory where you want your project to live, create a new project folder with a package.json file and install Koa:

# create a new project directory and change into it
mkdir nanobox-koa && cd nanobox-koa

# init a new project
npm init

# install Koa and save it as a dependency:
npm i koa --save

Create a file at the root of your new project called index.js with the following:

const Koa = require('koa');
const app = new Koa();

app.use(async ctx => {
  ctx.body = 'Hello Nanobox!';
});

app.listen(3000, () => console.log('App listening on port 3000!'))

Configure Your App

Nanobox uses a simple yaml config file called the boxfile.yml to build and configure your app's environment.

Add a boxfile.yml

Create a boxfile.yml in the root of your project with the following:

run.config:
  engine: nodejs
  extra_packages:
    - nginx

web.main:
  start:
    nginx: nginx -c /app/etc/nginx.conf
    koa: node index.js

data.db:
  image: nanobox/postgresql:9.5

NOTE: You may need to modify some boxfile configurations specific to your project (such as the database). You'll find more info on this in the docs and guides.

Test Your App Locally (optional)

Nanobox comes with a local development environment that allows you to run your app locally before you deploy it.

# (optional) add a DNS alias to access your app from the browser
nanobox dns add local koa.local

# start your app
nanobox run node index.js

If you added a DNS alias, access your app at koa.local:3000. If not, access it via the IP provided in the console after you've started your server.

Whenever you exit out of the Nanobox console, it'll shut down your VM and drop you back into your host OS.

Configure Koa

IMPORTANT: There are three important pieces of configuration that every application must have:

  • Your app must bind to all IP's (0.0.0.0). Why?
  • Your app must listen on port 8080. Why?
  • Your app must use environment variables (evars) to connect to Nanobox services. Why?

Koa binds to 0.0.0.0 by default, so no additional config is needed.

Update the Database Connection

When Nanobox spins up a database, it generates environment variables (evars) for the necessary connection credentials.

Koa is pretty free-form when it comes to configuring a database connection. However you choose to configure yours, you can access the following environment variables:

process.env.DATA_DB_HOST
process.env.DATA_DB_USER
process.env.DATA_DB_PASS

The following is an example database configuration using Postgres:

Install a Database Adapter

# install your database adapter (in this case postgres) and save it as a dependency
npm i pg-promise --save

NOTE: If you're using a different database (such as MongoDB) you'll need to install the corresponding adapter.

Create a Database Connection

const host = process.env.DATA_DB_HOST
const user = process.env.DATA_DB_USER
const pass = process.env.DATA_DB_PASS

const pgp = require('pg-promise')(/*options*/)
const db = pgp(`postgres://${user}:${pass}@${host}:5432/database`)

This is a very simple example of a database connection. The actual details will be up to you, based on the requirements of your application.

NOTE: Nanobox provides a default database named gonano, but you're welcome to create your own. Also, Nanobox will always use a service's default port when trying to connect. So in this example use 5432, Postgres' default.

Prepare Koa for Deploy

It's recommended to use an Nginx reverse proxy to serve static assets. Most Node frameworks are compiled and served static.

Create an etc/nginx.conf in your project with the following contents:

worker_processes 1;
daemon off;

events {
    worker_connections 1024;
}

http {
    include /data/etc/nginx/mime.types;
    sendfile on;

    gzip              on;
    gzip_http_version 1.0;
    gzip_proxied      any;
    gzip_min_length   500;
    gzip_disable      "MSIE [1-6]\.";
    gzip_types        text/plain text/xml text/css
                      text/comma-separated-values
                      text/javascript
                      application/x-javascript
                      application/atom+xml;

    # Proxy upstream to koa
    upstream koa {
        server 127.0.0.1:3000;
    }

    # Configuration for Nginx
    server {

        # Listen on port 8080
        listen 8080;

        # Settings to serve static files
        location ^~ /static/  {
            root /app/;
        }

        # Serve a static file (ex. favico)
        # outside /static directory
        location = /favico.ico  {
            root /app/favico.ico;
        }

        # Proxy connections to koa
        location / {
            proxy_pass         http://koa;
            proxy_redirect     off;
            proxy_set_header   Host $host;
        }
    }
}

That's it! On to the main event, deploying your application!

Setup Your GCP Account

If you haven't already, create a GCP account. In your admin panel's left-nav, go to "IAM & admin" > "Service Accounts" section.

GCP IAM & Admin > Service Accounts

Create a new service account with at least the following roles enabled:

  • Compute Instance Admin (v1)
  • Compute Network Admin
  • Compute Security Admin
  • Service Account Actor

GCP Service Account Roles

Select the "Furnish a new private key" option, save, and download the private key.

Add a New Provider to Your Nanobox Account

Add New Provider Account

Select Google Compute and click "Proceed."

Select Google Compute

Nanobox needs your GCP service email, service key, and project ID to authenticate with your GCP account and provision compute instances on your behalf. Paste in your key and click "Verify & Proceed."

Enter your GCP auth credentials

Name your provider and choose a default region. The name is arbitrary and only meant to help you identify it in your list of provider accounts.

Name your provider and select a default region

Launch a New App

Go to the home page of your Nanobox dashboard and click the "Launch New App" button. Select your GCP provider from the dropdown and choose the region in which you'd like to deploy your app.

Select your GCP provider

Confirm and click "Let's Go!" Nanobox will order a Compute instance under your GPC account. When the instance is up, Nanobox will provision platform components necessary for your app to run:

  • Load-Balancer: The public endpoint for your application. Routes and load-balances requests to web nodes.
  • Monitor: Monitors the health of your server(s) and application components.
  • Logger: Streams and stores your app's aggregated log stream.
  • Message Bus: Sends app information to the Nanobox dashboard.
  • Warehouse: Storage used for deploy packages, backups, etc.

Once all the platform components are provisioned and running, you're ready to deploy your app.

Stage Your App Locally

Nanobox provides "dry-run" functionality that simulates a full production deploy on your local machine. This step is optional, but recommended. If the app deploys successfully in a dry-run environment, it will work when deployed to your live environment.

nanobox deploy dry-run

More information about dry-run environments is available in the Dry-Run documentation.

Deploy

Add Your New App as a Remote

From the root of your project directory, add your newly created app as a remote.

nanobox remote add app-name

This connects your local codebase to your live app. More information about the remote command is available in the Nanobox Documentation.

Deploy to Your Live App

With your app added as a remote, you're ready to deploy.

nanobox deploy

Nanobox will compile and package your application code, send it up to your live app, provision all your app's components inside your live compute instance, network everything together, and BOOM! Your app will be live on GCP.

Manage & Scale

Once your app is deployed, Nanobox makes it easy to manage and scale your production infrastructure. In your Nanobox dashboard you'll find health metrics for all your app's instances/containers. Your application logs are streamed in your dashboard and can be streamed using the Nanobox CLI.

Although every app starts out on a single compute instance with containerized components, you can break components out into individual instances and/or scalable clusters through the Nanobox dashboard. Nanobox handles the deep DevOps stuff so you don't have to. Enjoy!

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FAQ

Why 0.0.0.0

Nanobox uses Docker to containerize your application within its own private network. Using 127.0.0.1 or localhost (the "loopback" IP) inside of a container will loopback to the container, not the host machine. In order for requests to reach your application, your application needs to listen on all available IP's.

Why Port 8080

Nanobox provides your application with a router that directs traffic through a private network created for your app. The router listens on ports 80 and 443, terminates SSL, and forwards all requests to port 8080.

Note: Your app/framework can listen on a port other than 8080, but you will need to implement a proxy that listens on 8080 and forwards to your custom port.

Why Use Environment Variables

Environment variables serve two purposes:

  • They obscure sensitive information in your codebase. Environment variables referenced in your code are populated at runtime, keeping potentially sensitive values out of your codebase.

  • Due to the dynamic nature of containerized applications, it's hard to predict the host IP of running services. These IP's are subject to change as your infrastructure changes. When creating your infrastructure, Nanobox knows what these values are and creates evars for necessary connection details.

Posted in Koa, Node.js, GCP, Deployment, Nanobox