AWT-LAB-V-SEM

Lab Record: Create Different Modules Using Node.js

Setup Instructions

Step 1: Create a New Project Directory

1. Open a terminal or command prompt.

2. Create a new directory for your project:

   mkdir node-modules-example
   cd node-modules-example
   

Step 2: Initialize a New Node.js Project

1. Initialize a new Node.js project using npm:

   npm init -y
   

   This will create a package.json file with default settings.

Step 3: Create a Module

1. Create a new file named math.js to define a module:

   // math.js
   const add = (a, b) => a + b;
   const subtract = (a, b) => a - b;
   
   module.exports = { add, subtract };
   

Step 4: Create the Main Application File

1. Create another file named app.js where we will use the created module:

   // app.js
   const math = require('./math');
   
   const a = 10;
   const b = 5;
   
   console.log(`Addition of ${a} and ${b} is: ${math.add(a, b)}`);
   console.log(`Subtraction of ${a} and ${b} is: ${math.subtract(a, b)}`);
   

Step 5: Run the Application

1. In the terminal, ensure you are in the project directory.

2. Execute the app.js file with Node.js:

   node app.js
   

3. You should see the following output:

   Addition of 10 and 5 is: 15
   Subtraction of 10 and 5 is: 5
   

Additional Module Examples

You can create additional modules to explore more functionality. Here are a couple of examples:

1. String Manipulation Module (stringUtils.js):

   // stringUtils.js
   const toUpperCase = (str) => str.toUpperCase();
   const toLowerCase = (str) => str.toLowerCase();
   
   module.exports = { toUpperCase, toLowerCase };
   

2. Date Formatting Module (dateUtils.js):

   // dateUtils.js
   const formatDate = (date) => date.toISOString().split('T')[0];
   
   module.exports = { formatDate };
   

Step 6: Using Third-Party Modules

1. Install a Third-Party Module

   • We will use the lodash library as an example. Install it by running:

     npm install lodash
     

2. Create a New File to Use Lodash
   • Create a file named lodashExample.js:

   // lodashExample.js
   const _ = require('lodash');
   
   const array = [1, 2, 3, 4, 5];
   
   // Get the last element of the array
   const lastElement = _.last(array);
   console.log(`The last element of the array is: ${lastElement}`);
   
   // Create a new array with doubled values
   const doubledArray = _.map(array, (num) => num * 2);
   console.log(`Doubled array: ${doubledArray}`);
   

Step 7: Run the Lodash Example

1. In the terminal, execute the lodashExample.js file with Node.js:

   node lodashExample.js
   

2. You should see the following output:

   The last element of the array is: 5
   Doubled array: [2, 4, 6, 8, 10]