Backend 03 - REST APIs and HTTP Methods

🗓️ Day - 3: REST APIs and HTTP Methods

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🌐 What are REST APIs?

• REST (Representational State Transfer) is a type of API that follows specific rules and guidelines for communication.

• It uses HTTP methods like:

  • GET

  • POST

  • PUT

  • DELETE

• It defines fixed standards for how requests and responses should be structured.

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📨 Ways to Send Data in Requests

1. req.body

• Hidden in the request payload.

• Best for larger, sensitive, or complex data (like passwords).

• Typically used in POST, PUT, and PATCH requests.

2. req.query

• Data sent in the URL after ? as key-value pairs.

• Ideal for small, optional parameters.

• Avoid using it for sensitive or complex data.

• Example:

    GET /search?gender=male&age=24
  

3. req.params

• Data sent as part of the API path.

• Commonly used for identifying specific resources.

• Example:

    GET /user/ankur_bit_io
  

• Accessed in code as:

    req.params.username
  

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🧾 REST API Methods

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💡 Example Use Case:
A social media app like x.com may use:

• req.params to fetch user profiles (/user/:username)

• req.query to filter search results (/search?gender=male)

• req.body for login forms or post creation

const express = require("express");

const app = express(); //server is created

//this is a middleware
app.use(express.json());

let notes = []

app.post("/notes", (req, res) => {
  console.log(req.body);
  notes.push(req.body)
  res.json({
    message:"notes added successfully",
    notes:notes
  })
});


//starting the server
app.listen(3000, () => {
  console.log("server is running on port 3000");
});

npx nodemon server.js //it checks continues changes on the server