Serverless Shopify App

This is a reference project to display how to create a Shopify App that is served from AWS using Lambda. Sound simple eh? Read on dear reader.

To build the Shopify App we'll use Node, React, Next and Koa. For the purposes of this reference app there will be very little server(less) side processing being done, but it is there so the app can be extended and made to be more useful.

The AWS side of things will be handled by serverless framework CLI and a few plugins to help us with specific functions.

Pre-requesites

An AWS account with an IAM user set up for programatic access. I started with a user with admin access (dont tell anyone) and then trimmed the access down once I determined which AWS services were being used. Seriously though, not having to fight with IAM as well as domains, certificates, cloudformation, s3, api gateway, lambda etc helped to keep me sane(ish)

Node, NVM.... It goes without saying that we'll need N# Serverless Shopify App This is a reference project to display how to create a Shopify App that is served from AWS using Lambda. Sound simple eh? Read on dear reader.

The AWS side of things will be handled by serverless framework CLI and a few plugins to help us with specific functions.

Pre-requesites

Node, NVM.... It goes without saying that we'll need Node, NVM always helps, git, editor and all of the other things.

Getting Started

Make sure that you have serverless installed. I've installed it globally here so you may need to sudo if you're on a mac or linux

$ npm i -g serverless

As serverless is a wrapper, in this instance, around AWS we'll have to give it IAM credentials. Save the key and secret when you create the IAM user, because you'll need them! Hide them somewhere safe. Set up serverless to connect to AWS using your IAM user.

$ serverless config credentials \ 
    --provider aws \ 
    --key xxxxxxxxxxxxxx \ 
    --secret xxxxxxxxxxxxxx

Next up is creating the serverless service. We'll specify that we are using Node and pass in the path where the service (and project) will live.

serverless create --template aws-nodejs --path serverless-shopify-app

Move in to the new serverless-shopify-app folder

$ cd serverless-shopify-app

and initialise it for npm

npm init -y

Now we have the packages.json file we can add some packages.

$ npm i --save \
    axios \
    koa \
    koa-session \
    @shopify/koa-shopify-auth \
    dotenv \
    isomorphic-fetch \
    next \
    react \
    react-dom \
    path-match \
    url \
    serverless-http \
    serverless-apigw-binary \
    serverless-domain-manager

While we are in the packages.json file add the following scripts. We'll use these later.

  "scripts": {
	"dev": "next",
	"build": "next build",
    "deploy": "next build && sls deploy"
  },

The serverless.yml is created with a bunch of example code. I deleted it and replaced it with this.

service: serverless-shopify-app

provider:
  name: aws
  runtime: nodejs12.x
  stage: ${self:custom.config.NODE_ENV}
  region: eu-west-2

functions:
  index:
    handler: handler.index
    events:
      - http: ANY /
      - http: ANY /{proxy+}

plugins:
  - serverless-apigw-binary
  - serverless-domain-manager

custom:
  secrets: ${file(config.json)}
  apigwBinary:
    types:
      - '*/*'
  customDomain:
    domainName: ${self:custom.config.DOMAIN}
    basePath: ''
    stage: ${self:custom.config.NODE_ENV}
    createRoute53Record: true

Add a new file config.json for our environment and domain settings

{
	"NODE_ENV": "production",
	"DOMAIN": "ssa.uark.uk"
}

A Super Simple Next App

Next create pages/index.js

const Index = () => (
	<div>
	  <p>Serverless Shopify App</p>
	</div>
  );
  
  export default Index;

Try building the next js app and check localhost:3000 in your browser

$ npm run dev

> [email protected] dev /Users/john/Code/serverless-shopify-app
> next

ready - started server on http://localhost:3000

The Shopify App

Log in to partner account
In Apps create a new app and choose Custom App
Add your name & url details
Add /auth/callback to the Allowed redirection URL(s) field
Add shopify keys to .env file

SHOPIFY_API_KEY='xxxxxxxxxxxxxxxx'
SHOPIFY_API_SECRET_KEY='xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'

Use serverless to deploy to aws

$ npm run deploy

When you first build and deploy your aws stack the subdomain that you are using may not exist. Run

$ sls create_domain

AWS Stuff

Need a domain in Route53

ode, NVM always helps, git, editor and all of the other things.