Shopify QR Code Generator App

Shopify Node app that enable merchants to create QR codes for specific products and track the number of scans for each QR code.

QR codes can include specific discounts, and can link to either the online store product page or directly to checkout with the product added to the cart.

It uses the Shopify App Template - Node

This is a template for building a Shopify app using Node and React. It contains the basics for building a Shopify app.

Rather than cloning this repo, you can use your preferred package manager and the Shopify CLI with these steps.

Benefits

Shopify apps are built on a variety of Shopify tools to create a great merchant experience. The create an app tutorial in our developer documentation will guide you through creating a Shopify app using this template.

The Node app template comes with the following out-of-the-box functionality:

• OAuth: Installing the app and granting permissions
• GraphQL Admin API: Querying or mutating Shopify admin data
• REST Admin API: Resource classes to interact with the API
• Shopify-specific tooling:
  • AppBridge
  • Polaris
  • Webhooks

Tech Stack

This template combines a number of third party open-source tools:

• Express builds the backend.
• Vite builds the React frontend.
• React Router is used for routing. We wrap this with file-based routing.
• React Query queries the Admin API.

The following Shopify tools complement these third-party tools to ease app development:

• Shopify API library adds OAuth to the Express backend. This lets users install the app and grant scope permissions.
• App Bridge React adds authentication to API requests in the frontend and renders components outside of the App’s iFrame.
• Polaris React is a powerful design system and component library that helps developers build high quality, consistent experiences for Shopify merchants.
• Custom hooks make authenticated requests to the Admin API.
• File-based routing makes creating new pages easier.

Getting started

Requirements

1. You must download and install Node.js if you don't already have it.
2. You must create a Shopify partner account if you don’t have one.
3. You must create a development store if you don’t have one.

Installing the template

This template can be installed using your preferred package manager:

Using yarn:

yarn create @shopify/app

Using npx:

npm init @shopify/app@latest

Using pnpm:

pnpm create @shopify/app@latest

This will clone the template and install the required dependencies.

Local Development

The Shopify CLI connects to an app in your Partners dashboard. It provides environment variables, runs commands in parallel, and updates application URLs for easier development.

You can develop locally using your preferred package manager. Run one of the following commands from the root of your app.

Using yarn:

yarn dev

Using npm:

npm run dev

Using pnpm:

pnpm run dev

Open the URL generated in your console. Once you grant permission to the app, you can start development.

Deployment

Application Storage

This template uses SQLite to store session data. The database is a file called database.sqlite which is automatically created in the root. This use of SQLite works in production if your app runs as a single instance.

The database that works best for you depends on the data your app needs and how it is queried. You can run your database of choice on a server yourself or host it with a SaaS company. Here’s a short list of databases providers that provide a free tier to get started:

Database	Type	Hosters
MySQL	SQL	Digital Ocean, Planet Scale, Amazon Aurora, Google Cloud SQL
PostgreSQL	SQL	Digital Ocean, Amazon Aurora, Google Cloud SQL
Redis	Key-value	Digital Ocean, Amazon MemoryDB
MongoDB	NoSQL / Document	Digital Ocean, MongoDB Atlas

To use one of these, you need to change your session storage configuration. To help, here’s a list of SessionStorage adapters.

Build

The frontend is a single page app. It requires the SHOPIFY_API_KEY, which you can find on the page for your app in your partners dashboard. Paste your app’s key in the command for the package manager of your choice:

Using yarn:

cd web/frontend/ && SHOPIFY_API_KEY=REPLACE_ME yarn build

Using npm:

cd web/frontend/ && SHOPIFY_API_KEY=REPLACE_ME npm run build

Using pnpm:

cd web/frontend/ && SHOPIFY_API_KEY=REPLACE_ME pnpm run build

You do not need to build the backend.

Hosting

When you're ready to set up your app in production, you can follow our deployment documentation to host your app on a cloud provider like Heroku or Fly.io.

When you reach the step for setting up environment variables, you also need to set the variable NODE_ENV=production.

Some things to watch out for

Using express.json middleware

If you use the express.json() middleware in your app and if you use Shopify.Webhooks.Registry.process() to process webhooks API calls from Shopify (which we recommend), the webhook processing must occur before calling app.use(express.json()). See the API documentation for more details.

Known issues

Hot module replacement and Firefox

When running the app with the CLI in development mode on Firefox, you might see your app constantly reloading when you access it. That happened in previous versions of the CLI, because of the way HMR websocket requests work.

We fixed this issue with v3.4.0 of the CLI, so after updating it, you can make the following changes to your app's web/frontend/vite.config.js file:

1. Change the definition hmrConfig object to be:

   const host = process.env.HOST
     ? process.env.HOST.replace(/https?:\/\//, "")
     : "localhost";
   
   let hmrConfig;
   if (host === "localhost") {
     hmrConfig = {
       protocol: "ws",
       host: "localhost",
       port: 64999,
       clientPort: 64999,
     };
   } else {
     hmrConfig = {
       protocol: "wss",
       host: host,
       port: process.env.FRONTEND_PORT,
       clientPort: 443,
     };
   }

2. Change the server.host setting in the configs to "localhost":

   server: {
     host: "localhost",
     ...

I can't get past the ngrok "Visit site" page

When you’re previewing your app or extension, you might see an ngrok interstitial page with a warning:

You are about to visit <id>.ngrok.io: Visit Site

If you click the Visit Site button, but continue to see this page, then you should run dev using an alternate tunnel URL that you run using tunneling software. We've validated that Cloudflare Tunnel works with this template.

To do that, you can install the cloudflared CLI tool, and run:

# Note that you can also use a different port
cloudflared tunnel --url http://localhost:3000

In a different terminal window, navigate to your app's root and call:

# Using yarn
yarn dev --tunnel-url https://tunnel-url:3000
# or using npm
npm run dev --tunnel-url https://tunnel-url:3000
# or using pnpm
pnpm dev --tunnel-url https://tunnel-url:3000

Developer resources

• Introduction to Shopify apps
• App authentication
• Shopify CLI
• Shopify API Library documentation