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Use Neon Postgres with Railway

Connect a Neon Postgres database to your Node application deployed with Railway

Railway is an application deployment platform that allows users to develop web applications locally, provision infrastructure and then deploy to the cloud. Railway integrates with GitHub for continuous deployment and supports a variety of programming languages and frameworks.

This guide shows how to deploy a simple Node.js application connected to a Neon Postgres database on Railway.

Prerequisites

To follow along with this guide, you will need:

  • A Neon account. If you do not have one, sign up at Neon. Your Neon project comes with a ready-to-use Postgres database named neondb. We'll use this database in the following examples.
  • A Railway account. If you do not have one, sign up at Railway to get started.
  • A GitHub account. Railway integrates with Gitub for continuous deployment. So, you'd need a GitHub account to upload your application code.
  • Node.js and npm installed on your local machine. We'll use Node.js to build and test the application locally.

Setting up your Neon database

Initialize a new project

  1. Log in to the Neon Console and navigate to the Projects section.

  2. Click the New Project button to create a new project.

  3. From your project dashboard, navigate to the SQL Editor from the sidebar, and run the following SQL command to create a new table in your database:

    CREATE TABLE plant_care_log (
        id SERIAL PRIMARY KEY,
        plant_name VARCHAR(255) NOT NULL,
        care_date DATE NOT NULL
    );

    Next, we insert some sample data into the plant_care_log table, so we can query it later:

    INSERT INTO plant_care_log (plant_name, care_date)
    VALUES
        ('Monstera', '2024-01-10'),
        ('Fiddle Leaf Fig', '2024-01-15'),
        ('Snake Plant', '2024-01-20'),
        ('Spider Plant', '2024-01-25'),
        ('Pothos', '2024-01-30');

Retrieve your Neon database connection string

Log in to the Neon Console and navigate to the Connection Details section to find your database connection string. It should look similar to this:

postgresql://alex:AbC123dEf@ep-cool-darkness-123456.us-east-2.aws.neon.tech/dbname?sslmode=require

Keep your connection string handy for later use.

Implementing the Node.js application

We'll create a simple Express application that connects to our Neon database and retrieves the list of plants tended to within the last month. Run the following commands in a terminal to set it up.

mkdir neon-railway-example && cd neon-railway-example
npm init -y && npm pkg set type="module"
npm install express pg
touch .env

We use the npm pkg set type="module" command to enable ES6 module support in our project. We also create a new .env file to store the DATABASE_URL environment variable, which we'll use to connect to our Neon database. Lastly, we install the pg library which is the Postgres driver we use to connect to our database.

# .env
DATABASE_URL=NEON_DATABASE_CONNECTION_STRING

Now, create a new file named index.js and add the following code:

import express from 'express';
import pkg from 'pg';

const app = express();
const port = process.env.PORT || 3000;

// Parse JSON bodies for this app
app.use(express.json());

// Create a new pool using your Neon database connection string
const { Pool } = pkg;
const pool = new Pool({ connectionString: process.env.DATABASE_URL });

app.get('/', async (req, res) => {
  try {
    // Fetch the list of plants from your database using the postgres connection
    const { rows } = await pool.query('SELECT * FROM plant_care_log;');
    res.json(rows);
  } catch (error) {
    console.error('Failed to fetch plants', error);
    res.status(500).json({ error: 'Internal Server Error' });
  }
});

// Start the server
app.listen(port, () => {
  console.log(`Server running on http://localhost:${port}`);
});

This code sets up an Express server that listens for requests on port 3000. When a request is made to the URL, the server queries the plant_care_log table in your Neon database and returns the results as JSON.

We can test this application locally by running:

node --env-file=.env index.js

Now, navigate to http://localhost:3000/ in your browser to check it returns the sample data from the plant_care_log table.

Push Your application to GitHub

To deploy your application to Railway, you need to push your code to a GitHub repository. Create a new repository on GitHub by navigating to GitHub - New Repo. You can then push your code to the new repository using the following commands:

echo "node_modules/" > .gitignore && echo ".env" >> .gitignore
echo "# neon-railway-example" >> README.md
git init && git add . && git commit -m "Initial commit"
git branch -M main
git remote add origin YOUR_GITHUB_REPO_URL
git push -u origin main

You can visit the GitHub repository to verify that your code has been pushed successfully.

Deploying to Railway

Creating a new Railway project

Log in to your Railway account and navigate to the dashboard. Click on the New Project button and select the Deploy from GitHub repo option. Pick the repository you created above, which sets off a Railway deployment.

Railway automatically figures out the type of application you're deploying and sets up the necessary build and start commands. However, we still need to add the DATABASE_URL environment variable to connect to our Neon database.

Select the project and navigate to the Variables tab. Add a new variable named DATABASE_URL and set its value to your Neon database connection string. You can redeploy the project by clicking on Redeploy from the context menu of the latest deployment.

Verify Deployment

Once the deployment completes and is marked as ACTIVE, Railway provides a public URL for accessing the web service. Visit the provided URL to verify that your application is running and can connect to your Neon database.

Whenever you update your code and push it to your GitHub repository, Railway will automatically build and deploy the changes to your web service.

Removing Your Application and Neon Project

To remove your application from Railway, select the project and navigate to the Settings tab. Scroll down to the end to find the "Delete Service" option.

To delete your Neon project, follow the steps outlined in the Neon documentation under Delete a project.

Source code

You can find the source code for the application described in this guide on GitHub.

Resources

Need help?

Join our Discord Server to ask questions or see what others are doing with Neon. Users on paid plans can open a support ticket from the console. For more details, see Getting Support.

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