Simple read REST API with Express.js and Node.js

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This short article shows how to create a simple read REST API with Node.js and Express.js.

Keywords: Node.js, Javascript, REST API, Express.js, Routing

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Required knowledge

In order to understand this article you will need at least basic knowledge of

• Javascript
• Linux
• Node.js
• NPM
• Express.js

Initialization

We will use the folder name rest-api-express-node. The following commands will initialize this folder for us:

mkdir rest-api-express-node
cd rest-api-express-node
npm init -y

Install express.js

npm install --save express

The implementation of a simple web server looks like the following:

Routing

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We need to specify routes for the web server. For this we will use another javascript file, routes.js.

This implementation will return the string REST API call of '/' every time the server root / is accessed. We will need to include this file in our index.js. The updated index.js looks like the following:

Route parameters

For this tutorial we will use route parameter feature of express.js. For more information see the express.js documentation. We will implement the query of a todo entry by using the following URL: /todos/:todoid. Route parameters are named URL segments that are used to capture the values specified at their position in the URL. In our example todoid is a route parameter, When this kind of URL is accessed, we will return a dummy todo entry which we will generate on the fly. We need to modify routes.js:

We can run the app:

node index.js

Enter http://localhost:3000/todos/123 to the URL in a browser.

This is just a very simple tutorial and test app to show the basics of using express routes and to return data in JSON format.

What are Future Plans for this Project?

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• Enhance with further operations: query, create, delete, update
• Enhance with database access

The final project can be accessed on my Github page:

nlharri/simple-read-rest-api-express-node