Medusa is an open source headless commerce platform targeted toward developers. It can be used to build fully-fledged online stores. It has a lot of essential ecommerce features including automated RMA flows, plug-and-play integrations, product and order management, and much more.
In this tutorial, you’ll learn how to create a comic book store with Medusa. You’ll also be adding important ecommerce features to your store including a search engine using MeiliSearch and a payment provider using PayPal.
You can find the full code for this tutorial on this GitHub repository.
Architecture Overview
Before getting started with the tutorial, here’s a short overview of Medusa’s architecture in case you’re not familiar with it. You can go ahead and skip to the next section if you are.
Medusa is made up of 3 primary components:
- The Headless Server is the core of your ecommerce store. It takes care of handling all logic, ecommerce features, and data. All other components connect to the server using REST APIs.
- The Medusa Admin is the user interface that store operators can use to view and manage their store’s data (for example, products and orders). Medusa provides an intuitive ready-made Admin panel that you can use. Alternatively, you can build your own and connect to the server using the REST APIs.
- The Storefront is the online store where customers view products and make purchases. Medusa provides two starter storefronts, one built with Next.js and one with Gatsby. You can also build a storefront with any framework of your choice and connect to the server using REST APIs.
In this tutorial, you’ll learn about setting up each and how to use them.
Prerequisites
Before you start you’ll need the following requirements installed:
- Node v14 or higher.
- Postgres with an empty database created.
- MeiliSearch for the search engine.
- A PayPal developer account.
- MinIO for file storage. You can alternatively use S3 or DigitalOcean Spaces.
Install Server
To install the Medusa server, you need to first install the Medusa CLI:
npm install -g @medusajs/medusa-cli
Then, run the following command to install the Medusa server in a new directory comic-store
:
medusa new comic-store
Install Plugins
The next step is to install the plugins you’ll be using on your Medusa server. For this tutorial, you need the plugins for the PayPal, MeiliSearch, and MinIO integrations.
Run the following command inside the comic-store
directory to install the 3 plugins:
npm install medusa-file-minio medusa-plugin-meilisearch medusa-payment-paypal
Replace
medusa-file-minio
with the file service you’re using if it’s not MinIO.
Make sure in package.json
that the versions for @medusajs/medusa
, medusa-interfaces
and @medusajs/medusa-cli
are greater than or equal to 1.3.0
. If not, update them with the following command:
npm install @medusajs/medusa@latest medusa-interfaces@latest @medusajs/medusa-cli@latest
Add Environment Variables
Medusa gives you the freedom to handle your environment variables based on your server. In this tutorial, you’ll be adding all environment variables in a .env
variable.
Open the .env
file. Add the following variables:
#PostgreSQL Database URL
DATABASE_URL=
#MinIO configurations
MINIO_ACCESS_KEY=
MINIO_SECRET_KEY=
MINIO_BUCKET=
MINIO_SERVER=
#PayPal Configurations
PAYPAL_SANDBOX=true
PAYPAL_CLIENT_ID=
PAYPAL_CLIENT_SECRET=
PAYPAL_AUTH_WEBHOOK_ID=
#MeiliSearch Configurations
MEILISEARCH_HOST=http://127.0.0.1:7700
MEILISEARCH_API_KEY=
These environment variables are important for configurations related to the database, MinIO, PayPal, and MeiliSearch.
DATABASE_URL
is the URL to connect to your PostgreSQL database schema. It should be of the format postgres://<USERNAME>:<PASSWORD>@<HOST>/<DB_NAME>
.
You can refer to our documentation to learn how to retrieve the necessary variables for MinIO and MeiliSearch.
If you’re using a different file service than MinIO please refer to the documentation of your file service to learn what variables you need.
For PayPal, you can refer to PayPal’s documentation to retrieve the Client ID, Client Secret, and Webhook ID. You also turned sandbox mode on for testing by setting PAYPAL_SANDBOX
to true
.
Configure Server
You need to pass these environment variables to the server configurations.
Server configurations are all in medusa-config.js
. This includes database, plugins, and more configurations.
Open medusa-config.js
. Add the following to the beginning of the file:
const dotenv = require('dotenv');
let ENV_FILE_NAME = '';
switch (process.env.NODE_ENV) {
case 'prod':
ENV_FILE_NAME = '.env';
break;
case 'test':
ENV_FILE_NAME = '.env.test';
break;
default:
ENV_FILE_NAME = '.env';
break;
}
dotenv.config({ path: process.cwd() + '/' + ENV_FILE_NAME });
This allows you to load environment variables from a .env
file.
Next, in the plugins
array, add the following 3 plugins at the end of the array:
const plugins = [
//...
{
resolve: `medusa-payment-paypal`,
options: {
sandbox: process.env.PAYPAL_SANDBOX,
client_id: process.env.PAYPAL_CLIENT_ID,
client_secret: process.env.PAYPAL_CLIENT_SECRET,
auth_webhook_id: process.env.PAYPAL_AUTH_WEBHOOK_ID
}
},
{
resolve: `medusa-file-minio`,
options: {
endpoint: process.env.MINIO_SERVER,
bucket: process.env.MINIO_BUCKET,
access_key_id: process.env.MINIO_ACCESS_KEY,
secret_access_key: process.env.MINIO_SECRET_KEY,
}
},
{
resolve: `medusa-plugin-meilisearch`,
options: {
config: {
host: process.env.MEILISEARCH_HOST,
apiKey: process.env.MEILISEARCH_API_KEY
},
settings: {
products: {
searchableAttributes: ["title", "description", "variant_sku"],
displayedAttributes: ["title", "description", "variant_sku"],
},
},
},
}
];
This loads the 3 plugins you installed earlier and passes the necessary options for each.
Finally, change the database configurations in projectConfig
in the exported function to use your PostgreSQL database instead of an SQLite database:
module.exports = {
projectConfig: {
//...
database_url: DATABASE_URL,
database_type: "postgres",
//**comment out or remove these lines:**
// database_database: "./medusa-db.sql",
// database_type: "sqlite",
},
//...
};
Migrate and Seed Database
The final step before running your server is migrating and seeding your database. Migration means adding the necessary tables into your database schema to make it work with Medusa.
Seeding means adding dummy data into your database to quickly get started.
Run the following command to migrate and seed your database:
npm run seed
This will connect to your database using the URL you passed to the environment variable DATABASE_URL
. Make sure that you already created the database before running this command.
Run the Server
Make sure that the MeiliSearch and MinIO services are running. Then, run your server with the following command:
npm start
This will run your server on the port 9000
. You should keep the server running for the entire tutorial, as the Medusa admin and storefront depend on the server.
Setup Medusa Admin
In this section, you’ll install the Medusa Admin, add products to it, and enable PayPal as a payment provider.
Install Admin
In your terminal and in a different directory than the comic-store
directory, run the following command:
git clone https://github.com/medusajs/admin comic-admin
Then, change to the newly created comic-admin
directory and install the necessary dependencies:
cd comic-admin
npm install
Make sure the Medusa server is still running. Then, run the following command to start the admin:
npm start
This will start your Medusa admin on the port 7000
by default. Open it in your browser and you should see a login screen.
You can use the default email “admin@medusa-test.com” and password “supersecret” to log in.
Add Products
After you log in, choose from the sidebar “Products”. You’ll see a few products that were added when you seeded your database.
Go ahead and delete those by clicking on the 3 dots for each one then Delete.
Next, add products to your comic book store by clicking the “New Product” button at the top right.
You need to fill out the fields related to the product info.
Add as many products as you want before moving on to the next step.
Enable PayPal
To enable PayPal as a payment provider, click on Settings, then choose Regions.
For each region you want to add PayPal as a payment provider, click on the “Payment Providers” input and choose “paypal”, then click Save.
Setup the Storefront
The last step is to set up the storefront. This section covers installing the Gatsby storefront, making some customizations to it, adding MeiliSearch bar, and adding the UI for PayPal.
Install Storefront
In your terminal and in a different directory than the comic-store
and comic-admin
directories, run the following command:
gatsby new comic-storefront https://github.com/medusajs/gatsby-starter-medusa
This will install the Gatsby storefront in a new directory comic-storefront
.
Then, change to the comic-storefront
directory and rename .env.template
to .env.development
:
mv .env.template .env.development
Add Environment Variables
You need to add environment variables to use MeiliSearch and PayPal on your storefront. In .env.development
add the following variables:
#MeiliSearch Configurations
GATSBY_MEILISEARCH_HOST=
GATSBY_MEILISEARCH_API_KEY=
#PayPal Configurations
GATSBY_PAYPAL_CLIENT_ID=
The values for these configurations are the same as those you used on your server.
Run Gatsby Storefront
Make sure that the Medusa server is running. Then run the following command to start the Gatsby storefront:
npm start
This will run your storefront on localhost:8000
. Open it in your browser. You should see a hero image and the products you added.
Customize Storefront
The hero banner is a static one that is added to the code. You’ll now customize it to show something related to your comic book store.
Open src/pages/index.js
. You should find in the returned JSX the component StaticImage
followed by a div. Change them to the following:
<StaticImage
src="../images/hero.png"
alt="A black Medusa hoodie and a white Medusa coffee mug"
placeholder="tracedSVG"
className="w-full lg:w-1/2 h-auto lg:my-5"
/>
<div className="lg:ml-7">
<h1 className="text-4xl">The Best Comic Books</h1>
<p className="mt-2 text-lg font-normal">
Buy the best Marvel and DC Comic Books!
</p>
</div>
This changes the text and image used. You can download the new image from here. Place it at src/images
with the name hero.png
.
If you open your storefront now you should see the hero image updated.
Add Search Bar
In this section, you’ll add a search bar to search products using MeiliSearch.
In your terminal, run the following command to install some necessary dependencies:
npm install react-instantsearch-dom @meilisearch/instant-meilisearch
Then, create the file src/components/header/search.jsx
with the following content:
import {
Highlight,
Hits,
InstantSearch,
SearchBox,
connectStateResults
} from "react-instantsearch-dom"
import React from "react"
import { instantMeiliSearch } from "@meilisearch/instant-meilisearch"
const searchClient = instantMeiliSearch(
process.env.GATSBY_MEILISEARCH_HOST,
process.env.GATSBY_MEILISEARCH_API_KEY
)
const Search = () => {
const Results = connectStateResults(({ searchState, searchResults, children }) =>
searchState && searchState.query && searchResults && searchResults.nbHits !== 0 ? (
<div className="absolute top-full w-full p-2 bg-gray-200 shadow-md">
{children}
</div>
) : (
<div></div>
)
);
return (
<div className="relative">
<InstantSearch indexName="products" searchClient={searchClient}>
<SearchBox submit={null} reset={null} />
<Results>
<Hits hitComponent={Hit} />
</Results>
</InstantSearch>
</div>
)
}
const Hit = ({ hit }) => {
return (
<div key={hit.id} className="relative">
<div className="hit-name">
<Highlight attribute="title" hit={hit} tagName="mark" />
</div>
</div>
)
}
export default Search;
This creates a search client using the method instantMeiliSearch
that is exported from the dependency @meilisearch/instant-meilisearch
which you just installed. You pass the method the environment variables you added earlier for the configurations.
The Search
component then displays a search bar using components from react-instantsearch-dom
. When the user enters a query and there are results, each result is rendered using the Hit
component.
If you want to learn more about how you can customize the UI of the search bar and its options you can check out the documentation of React InstantSearch by Algolia.
Next, you’ll add the search bar to the navigation bar. To do that, open index.jsx
and import the Search
component at the beginning of the file:
import Search from "./search"
Then, in the returned JSX add the Search
component before RegionPopover
:
//...
<Search />
<RegionPopover regions={mockData.regions} />
//...
Save all changes and open the storefront now. You should see a search bar in the navigation bar. Try to enter the name of one of your products and you should see it in the result.
Add PayPal UI
In this section, you’ll add the UI necessary to use PayPal as a payment method.
In your terminal use the following command to install PayPal’s React library:
npm install @paypal/react-paypal-js
Then, create the file src/components/payment/paypal-payment/index.jsx
with the following content:
import { PayPalButtons, PayPalScriptProvider } from "@paypal/react-paypal-js";
import React, { useMemo, useState } from "react";
import { navigate } from "gatsby"
import { useCart } from "../../../hooks/use-cart"
import { useMedusa } from "../../../hooks/use-medusa";
const paypalClientId = process.env.GATSBY_PAYPAL_CLIENT_ID || ""
const PaypalPayment = () => {
const {
cart,
actions: { completeCart, setPaymentSession },
} = useCart()
const [errorMessage, setErrorMessage] = useState(undefined)
const [processing, setProcessing] = useState(false)
const client = useMedusa()
const paypalSession = useMemo(() => {
if (cart.payment_sessions) {
return cart.payment_sessions.find(s => s.provider_id === "paypal")
}
return null
}, [cart.payment_sessions])
if (!paypalSession) {
return null
}
const completeOrder = async (authorizationOrder) => {
const cart = await setPaymentSession("paypal")
if (!cart) {
setProcessing(false)
return
}
await client.carts.updatePaymentSession(cart.id, "paypal", {
data: {
data: {
...authorizationOrder
}
}
});
const order = await completeCart(cart.id)
if (!order || order.object !== "order") {
setProcessing(false)
return
}
setProcessing(false)
navigate("/order-confirmed", { state: { order } })
}
const handlePayment = (data, actions) => {
actions.order.authorize().then((authorization) => {
if (authorization.status !== 'COMPLETED') {
setErrorMessage(`An error occurred, status: ${authorization.status}`);
setProcessing(false);
return;
}
completeOrder(authorization)
})
}
return (
<PayPalScriptProvider options={{
"client-id": paypalClientId,
"currency": cart.region.currency_code.toUpperCase(),
"intent": "authorize"
}}>
{errorMessage && (
<span className="text-rose-500 mt-4">{errorMessage}</span>
)}
<PayPalButtons
style={{ layout: "horizontal" }}
onApprove={handlePayment}
disabled={processing}
/>
</PayPalScriptProvider>
)
}
export default PaypalPayment;
To briefly explain this code snippet:
- You render a PayPal button that allows customers to pay with PayPal using components from
@paypal/react-paypal-js
which you just installed. You pass the componentPayPalScriptProvider
the PayPal client ID from the environment variables. - When the button is clicked, the method
handlePayment
is executed which initiates authorization with PayPal using the methodactions.order.authorize()
. This opens PayPal’s payment portal in a new window. - After the customer successfully completes payment, the fulfillment callback function passed to
then
is executed. If there are any errors in the authorization, an error message will be shown. Otherwise, thecompleteOrder
method will be called. - In the
completeOrder
method, PayPal is first set as the payment session of the current cart. Then, it is updated on the server with data that is received from PayPal after the customer authorized the payment. - Finally, the order is placed and the customer is redirected to the
order-confirmed
page where they can see a summary of their order details.
Next, in src/components/payment/index.jsx
add an import for the PaypalPayment
component at the beginning of the file:
import PaypalPayment from "./paypal-payment"
Then, in the returned JSX you’ll find a switch statement that renders components based on the ID of the payment provider. Add a new case to the switch statement before the default
case. This renders PaypalPayment
when the ID of the payment provider available for the customer is paypal
:
switch (ps.provider_id) {
case "stripe":
//...
case "manual":
//...
case "paypal":
return <PaypalPayment />
default:
return null
}
Save all changes before moving on to test the entire flow.
Test Checkout Flow
In this section, you’ll test placing an order on the storefront, then viewing the details on the admin and capturing payment.
Make sure that all 3 components (Medusa server, Medusa admin, and storefront) are running. Then, on your storefront, choose a product and it to cart.
Then, click on the cart icon and click on the “Checkout” button in the popup.
You’ll be taken to a one-page checkout where you have to enter your details and choose a shipping method.
Once you reach the last step of the checkout you should see the available payment methods in the current region including PayPal.
If you can’t see PayPal, make sure the correct region is selected at the top right of the navigation bar.
Try paying with PayPal by clicking on the first PayPal button. A new page will open where you’re asked to login to PayPal and authorize the payment.
Once you authorize the payment with a sandbox account, you’ll be taken back to the storefront. If the authorization was successful, you’ll shortly be redirected to the Order Summary page.
On your Medusa admin, click on Orders in the sidebar. You should see a new order.
Click on the order. You’ll see the order details including the items ordered and payment details.
To capture the payment, click on the “Capture payment” button.
What’s Next?
You just created a comic book store using Medusa that has a search engine using MeiliSearch and PayPal as a payment provider.
There’s much more that you can do with your ecommerce store:
- Check more plugins that you can add to add more features to your ecommerce store, including using Strapi for CMS.
- Customize your Medusa Server by adding custom endpoints.
- Deploy the server on Heroku and the Medusa Admin and Storefront on Netlify.
Should you have any issues or questions related to Medusa, then feel free to reach out to the Medusa team via Discord.