What is an API?

API or application programming interface allow two software components to communicate with one another with a set of definitions and protocols. APIs allow developers to extend current functionaity without having to start from scratch, by defining standardised ways for different software components to connect with one another.

APIs make it easy to only share the necessary information while keeping other internal system details hidden, which helps in improving system security.

How do APIs work?

Consider API communication as a  request and response between a client and server. Client is the application that makes the request, and the server responds to it. API serves as a link that connects them.

1. Request: The process starts with a request from a client. The request being made could be for data access, an action, or making use of a particular function offered by the server.
2. API Call: The client submits its request to the server through the API. This involves submitting structured data, like HTTP requests containing a set of parameters or payloads, and then directed to the specified endpoint of the API.
3. Processing: When the API receives the request, it validates according to its specified rules and regulations. This involves analysing and verifying arguments, authentication credentials, and it confirms the request made by the client meets the APIs expectations.
4. Action: After the request is validated,  API communicates with the system to perform the requested action, which includes getting data from a database, running actions, making operations or calling other services.
5. Response: Once the requested action is completed, API provides a response which contains the operations outcome, and this response will be sent back to the client.
6. Handling Response: After getting the response, client uses it in accordance with its requirements, which includes taking additional actions based on the provided information.

Types of APIs

1. REST API: Representational State Transfer{REST) APIs use HTTP methods(GET. POST, PUT and DELETE) to conduct CURD operations. They commonly use stateless communication and URI(uniform Resource Identifier) to identify resources.
2. WebSocket APIs: It allows real-time communication between the server and client, making them perfect for applications that need regular updates.
3. Public APIs: It is often used by companies or organisations to make their products and services known to the general public.
4. Private APIs: They are not available to external developers, it is an internal API used within a company to provide access to their internal data.

What is nodejs?

Node.js is an open-source, cross-platform javascript runtime environment that enables developers to execute Javascript code on the server. Executes JavaScript code outside of a web browser using V8 Javascript engine, which was designed for use in Chrome.

Features of Nodejs:

Single-Threaded: Node.js utilises a single-threaded desgin with event looping, which makes it extremely scalable. As compared to standard servers such as Apache HTTP server, Node.js utilises a single-threaded program which is capable of handling a higher number of requests.

Asynchronous and event-Driven: Node.js is non-blocking and event-driven in nature, allowing it to handle many concurrent connections. It uses a notification mechanism called events to process incoming requests asynchronously.

Scalability: node.js is highly scalable and most organisations demand scalable software.  It is capable of handling concurrent connections efficiently. It is appropriate for developing microservices and distributed systems in which scalability and performance are crucial.

Cross-Platform Compatibilty: Node.js can run on a number of opearting systems like Windows, macOS and Linux.

Uses javaScript: Most of the developers use javaScript and Node.js allows developers to use JavaScript for both client-side and server-side development.

Installing Node.js and npm

To start creating an API  with node.js, the first step is to install Node.js and npm (Node Package Manager).

Step 1: Install Node.js, visit the official Node.js website(nodejs.org)  and download the installer appropriate for your operating system.

Step 2: After the installation is completed, verify whether nodejs and npm is successfully installed on your system by opening a terminal or command prompt.

Step 3: Once it is successfully installed run the following command to check node.js version: node-v and to check npm version it is: npm –v.

Output should look like this: The versions are displayed and it confirms that the installation is successful.

Steps to create an API in nodejs:

Step 1: Create a project folder using mkdir command in your terminal. Lets name it my-api. And ype mkdir my-api in your command prompt.

Step 2: Go to the Project folder, enter the cd command followed by your project folder in your command prompt. cd my-api. This will take you to the project folder.

Step 3: Create a Node.js file in the project directory, I have created it as server.js

Step 4: Import the necessary modules.

In this I have installed express, express-winston, cors

Step 5: This code set up middleware in express.js application

Step 6: Create routes for your API, for instance:

Step 7: Start the Server and listen on a specific port.

Step 8: Run the server, open the terminal and navigate to project directory and run the server using command: node server.js

Step 9: Designing API endpoints,  define endpoints for different HTTP methods(GET, POST, PUT, DELETE), for instance:

You can access your endpoints in a web browser or via HTTP client tools like postman. To access the endpoint go to ‘http://localhost:8000’ and access hello endpoint, for example ‘http://localhost:8000/hello’.

You can define additional endpoints to access particular endpoints based on what you want to explore.

Step10: Test your API, you can use cURL or Postman.

Conclusion

In conclusion, creating an API in Node.js includes generating endpoints, using frameworks like Express.js, properly testing  and exporting to a server or a cloud platform. With Node.js cross-platform compatibility and a large environment of modules and packages, developers can create APIs that support the needs of web applications.

Contact  info@simplileap.com  for any queries.

Nirmitha

Driven by a relentless desire to learn and grow, I find myself exploring the domains of technology and web development. With boundless passion I am dedicated to progressing in my career and making significant contributions to the tech sector.