"Unlocking the Power of APIs: How to Obtain a Dropdown Menu and Store it in a Database"

In the fast-paced and interconnected digital landscape, Application Programming Interfaces (APIs) have emerged as the driving force behind seamless connectivity, collaboration, and innovation. APIs act as bridges between different software systems, allowing them to communicate, share data, and perform functions that enhance the overall user experience. As businesses strive for efficiency and adaptability, unlocking the power of APIs has become a strategic imperative.

How to Obtain a Dropdown Menu and Store it in a Database

Here, we will start how to gain dropdown menu via API nodejs express and when user choose any menu then data will store in Mongodb Database. In nodejs there is potential to make a API with the help of any End-point like you know about API how is look like !! right.

Let's define first how is Actually Nodejs, expressjs, after that we will see about mongodb and how can we store it. Okay!!!

Nodejs is a powerful, open-source, server-side runtime environment that allows developers to build scalable and high-performance network applications. It is built on the chrome V8 javascript runtime and uses an event-driven, such as web servers, chat applications, and online gaming platforms.

Here are key aspects of Node.js:

JavaScript Runtime:

Node.js allows developers to use JavaScript for server-side scripting. This unifies the language used for both client-side and server-side development, which can streamline the development process.

What is MongoDB

MongoDB is a popular open-source NoSQL (non-relational) database management system. NoSQL means no structure like it is look like an object while in SQL it is a structure query language like SELECT CustomerName, City FROM Customers; (The SELECT statement is used to select data from a database.) But NoSQL database is useless...NOT completely because of whenever we want add extra column in database then it is possible through NoSQL MongoDB.   

MongoDB installation - CLICK HERE

MongoDB Basic Command - CLICK HERE

About MongoDB vs SQL - CLICK HERE

CRUD in MongoDB - CLICK HERE

Object Like - 

{
  "_id": {
    "$oid": "659ad46e0382148123c82841"
  },
  "name": "moto G60",
  "brand": "motorola",
  "price": 16500,
  "category": "mobile"
}

MongoDB is a type of database that helps store and manage large amounts of data in a flexible and scalable way. Unlike SQL, MongoDB doesn't require a fixed structure for the data, allowing you to store information in a more versatile format.

• MongoDB is a NoSQL database.
• The data stored in a collection
• Collection don't have row and columns
• Data is stored in the form of object.

Reactjs Application

Here, we will start from reactjs application and create a new project, after that in src folder create a new folder like components and inside this components folder create a file called as Dropdown.jsx. In App.jsx file, we need to add Dropdown.jsx file add to the app.jsx file.

Now its coding time

Dropdown.jsx

import React from 'react'

function Dropdown() {
  

  return (
    
    <div>
    <p>Dropdown</p>
    </div>
  
  );
}

export default Dropdown;

Now create a three useState();

import React, { useEffect, useState } from "react";

function Dropdown() {

  const [designation, setDesignation] = useState();
  const [dropdownData, setDropdowndata] = useState([]);
  const [selectedOption, setSelectedOption] = useState("");


  return (
    
    <div>
    <p>Dropdown</p>
    </div>
  
  );
}

export default Dropdown;

now this some we are trying to create a interface of dropdown menu and submit button

import React, { useEffect, useState } from "react";

function Dropdown() {

  const [designation, setDesignation] = useState();
  const [dropdownData, setDropdowndata] = useState([]);
  const [selectedOption, setSelectedOption] = useState("");


  return (
    
    <div class="grid grid-cols-1  ml-20 mt-[50px] mr-20  ">
        <div class="flex flex-wrap -mx-3 mb-6">
          <div class="w-full md:w-1/2 px-3 mb-6 md:mb-0">
            <div class="w-full md:w-1/2 px-3 mb-6 md:mb-0">
              <label
                class="block uppercase tracking-wide text-gray-700 text-xs font-bold mb-2"
                for="Designation"
              >
                Designation
              </label>

              <select
                value={selectedOption}
                onChange={(e) => setSelectedOption(e.target.value)}
                className="dropdown-button  w-full bg-white p-2 border text-xs/[12px] py-3 px-4 "
              >
                <option
                  value={designation}
                  onChange={(e) => setDesignation(e.target.value)}
                  disabled
                >
                  Select an option
                </option>
                {dropdownData.map((option) => (
                  <option key={option} value={option}>
                    {option}
                  </option>
                ))}
              </select>

              {selectedOption && <p>You selected: {selectedOption}</p>}
            </div>

            <button
              className="bg-blue-600 text-white pt-2 pb-2 pr-3 pl-3 mt-3 ml-3"
              onClick={handleSubmit}
            >
              Add Employee
            </button>
          </div>
        </div>
      </div>
  );
}

export default Dropdown;

Handle the data but this time check our code very carefully becuase of we have to used API and fetch the Dropdown menu from API nodejs. okay!!

complete reactjs application

import axios from "axios";
import React, { useEffect, useState } from "react";

function Dropdown() {
  const [designation, setDesignation] = useState();

  const [dropdownData, setDropdowndata] = useState([]);
  const [selectedOption, setSelectedOption] = useState("");
  

  const handleSubmit = async () => {
    try {
      const response = await axios.post(
        "http://localhost:8000/createEmployee",
        {
          designation: selectedOption,
        }
      );
      if (response.status === 200) {
        console.log("Status is good");
      }
      console.log(response);
      console.log(response.data);
      setDesignation('');
    } catch (error) {
      console.log("Error adding employeeData", error.message);
    }
  };

  useEffect(() => {
    const fetchData = async () => {
      try {
        const response = await axios.get("http://localhost:8000/api/dropdown");
        setDropdowndata(response.data);
      } catch (error) {
        console.log("Error fetching dropdown data: ", error.message);
      }
    };

    fetchData();
  }, []);

  return (
    <div>
      <div class="grid grid-cols-1  ml-20 mt-[50px] mr-20  ">
        <div class="flex flex-wrap -mx-3 mb-6">
          <div class="w-full md:w-1/2 px-3 mb-6 md:mb-0">
            <div class="w-full md:w-1/2 px-3 mb-6 md:mb-0">
              <label
                class="block uppercase tracking-wide text-gray-700 text-xs font-bold mb-2"
                for="Designation"
              >
                Designation
              </label>

              <select
                value={selectedOption}
                onChange={(e) => setSelectedOption(e.target.value)}
                className="dropdown-button  w-full bg-white p-2 border text-xs/[12px] py-3 px-4 "
              >
                <option
                  value={designation}
                  onChange={(e) => setDesignation(e.target.value)}
                  disabled
                >
                  Select an option
                </option>
                {dropdownData.map((option) => (
                  <option key={option} value={option}>
                    {option}
                  </option>
                ))}
              </select>

              {selectedOption && <p>You selected: {selectedOption}</p>}
            </div>

            <button
              className="bg-blue-600 text-white pt-2 pb-2 pr-3 pl-3 mt-3 ml-3"
              onClick={handleSubmit}
            >
              Add Employee
            </button>
          </div>
        </div>
      </div>
    </div>
  );
}

export default Dropdown;

const response = await axios.post("http://localhost:8000/createEmployee");
const response = await axios.get("http://localhost:8000/api/dropdown");


NOTE :- You can add these lines only when you have created the API in NodeJS.

in App.jsx file, we will import our dropdown.jsx file.

finally run this application. By this command npm run dev

NOTE :- At this time please ignore Dropdown data as we have not created the API yet.

MongodDB Database

Why we are building mongodb database and collection(table) because we will need conection URL to connect in nodejs and also we will need database name and collection name.

after installing mongodb compass in your system simply open it and copy the url and click connect button.

After click on button then we have some command for you, by the use this command you can simply create database and its collection .

- show dbs   (database check)
- use optionmenu (create db)
- db.createCollection('employeedatas')  (create table)
- show collections (check table - by default we don't any data because of not yet wr create a any data)

Nodejs - Expressjs API

Here, first we need to install to some pkg in server side application because of we need to some pkg for make API purpose.

npm init
npm i express
npm i mongodb  (mongodb connection)
npm i cors
npm i nodemon -g (for run our server side application, -g means globaly)
npm i mongoose  (it is driver for connection of nodejs and mongodb)

Create a new folder called as server outside of reactjs application project folder and open cmd prompt in server directory and install one by one pkg.

server.js

First, we will create a folder called as mongodb and inside this folder we will create a file called as config.js

const mongoose = require('mongoose')
mongoose.connect("mongodb://127.0.0.1:27017/optionmenu")

optionmenu - it is our database name.

mongodb://127.0.0.1:27017/ - it is our connection url when open mongodb you get it.

const express = require('express');

const cors = require('cors');

const app = express();
app.use(cors());
app.use(express.json());


const DropDownOptions = ['HR', 'Manager', 'Employee'];


app.get('/api/dropdown', (req, resp) => {
    resp.json(DropDownOptions)
})

app.listen(8000, () => {
    console.log('Server is running on port 8000');
})

Then simply run nodemon server.js file in vs code terminal.

Now we will check in our postman for dropdown data is coming or not.

Yupee!! We got it.

again we will create a new API for uploading the data when user select dropdown menu options and store it. 

but before creating a new API, lets make schemas and model. For this first create a new folder called as schema and inside this folder create a file employee.js.

1. importing the mongoose.

This line imports the Mongoose library, which is a popular ODM (Object Data Modeling) library for MongoDB and Node.js. It provides a way to define schemas, interact with the MongoDB database, and perform various operations.

const mongoose = require('mongoose');

 

2. Defining a Mongoose Schema:

 const employeeSchema = new mongoose.Schema 

({

designation: String,

})

This code creates a Mongoose schema for the "employeeData" collection. The schema specifies that documents in this collection should have a field named "designation" of type String. This is a basic example, and in a real-world scenario, you would include more fields and specify their types.

 3. Exporting the Mongoose Model

module.exports = mongoose.model('employeeData', employeeSchema)

The code exports a Mongoose model based on the defined schema. The mongoose.model function takes two arguments:

The first argument ('employeeData') is the name of the MongoDB collection. This name is case-sensitive and is typically given in the singular form.

The second argument (employeeSchema) is the schema definition. By exporting this model, you can use it in other parts of your application to interact with the MongoDB collection named "employeeData."

app.post('/createEmployee', async (req, resp) => {
    try {
        const {
            designation
        } = req.body;
        const newEmployee = new employee({
       designation
        });
        await newEmployee.save();

        resp.status(200).json({message: 'Employee created successfully'})
    } catch(error){
        resp.status(500).json({message: 'Internal Server Error'});
    }
});

Server.js

const express = require('express');
require('./mongodb/config')
const employee = require('./schema/employee')

const cors = require('cors');

const app = express();
app.use(cors());
app.use(express.json());

app.post('/createEmployee', async (req, resp) => {
    try {
        const {
            designation
        } = req.body;
        const newEmployee = new employee({
       designation
        });
        await newEmployee.save();

        resp.status(200).json({message: 'Employee created successfully'})
    } catch(error){
        resp.status(500).json({message: 'Inernal Server Error'});
    }
});


const DropDownOptions = ['HR', 'Manager', 'Employee'];


app.get('/api/dropdown', (req, resp) => {
    resp.json(DropDownOptions)
})

app.listen(8000, () => {
    console.log('Server is running on port 8000');
})

Finally our time is come. 

Disclaimer

Events and Event Emitter in nodejs

This blog we have seen mongodb basic and how is it work with installation and after installation, we have already seen mongodb basic, CRUD operation, connect mongodb with nodejs, read, update, delete, POST, GET API etc. we should not face any problem while making Database, collection(table) and using the data in nodejs even whenever we will make API. Read data from mongodb in nodejs

• # What is Mongoose
• # Install Mongoose
  
• # What is Events and Event Emitter
  
• # Make an event and call it
  

Now in this blog  we will use mongoose. There is an npm package to connect nodes to mongodb. Mongoose is a MongoDB object modeling tool designed to work in an asynchronous environment. They created mongoose by improving mongodb, with the help of which you can create schemas and models of mongoose's movements.

Suppose that there are 4 fields in our database (like name, brand, price, category) and the user wants to add a 5th field also (like color) but we want to add only 4 fields, for this we create schemas.

Here you can also define TYPE in schemas like price type is numeric but if any user wants to use quotes (" " ' ') then we can stop the user for this.

in sort we can apply validation in mongoose but we can't in directly mongodb.

 What is MongoDB

MongoDB is a popular open-source NoSQL (non-relational) database management system. NoSQL means no structure like it is look like an object while in SQL it is a structure query language like SELECT CustomerName, City FROM Customers; (The SELECT statement is used to select data from a database.) But NoSQL database is useless...NOT completely because of whenever we want add extra column in database then it is possible through NoSQL MongoDB.   

MongoDB installation - CLICK HERE

MongoDB Basic Command - CLICK HERE

About MongoDB vs SQL - CLICK HERE

CRUD in MongoDB - CLICK HERE

Object Like - 

{
  "_id": {
    "$oid": "659ad46e0382148123c82841"
  },
  "name": "moto G60",
  "brand": "motorola",
  "price": 16500,
  "category": "mobile"
}

MongoDB is a type of database that helps store and manage large amounts of data in a flexible and scalable way. Unlike SQL, MongoDB doesn't require a fixed structure for the data, allowing you to store information in a more versatile format.

• MongoDB is a NoSQL database.
• The data stored in a collection
• Collection don't have row and columns
• Data is stored in the form of object.

Install Mongoose

For this you need to copy this (npm i mongoose) and paste it in project's terminal.

What is Events and Event Emitter

In nodejs, an event is an action or occurrence that can be observed and responded to . Node.js provides the event emitter pattern as a core module to handle events. The Event emitter is an implementation of the observer pattern allowing objects (event emitter) to emit the named events that cause function objects (listeners) to be called.

OR

if i will use button in HTML and add the onClick event and whenever we click on button and generate the function and get a signal that please call the function and execute the code.

and the event is that which observes the singal received from the event and works on that pattern.

Basic Usage:

To use the Event Emitter, you first create an instance of Event Emitter.

You can then use the .on(eventName, listener) method to attach a listener function to a specific event.

The .emit(eventName, ...args) method is used to emit (trigger) an event, and any attached listeners for that event are called.

Q) How can we make a button in Node.js ?

 Ans - Through API and use Event Emitter

Make an event and call it

First we will make a API and import express and EventEmitter (EventEmitter is inbuilt module in nodejs) so don't need to install in nodejs.

const express = require('express')
const EventEmitter = require('events');
const app = express()


app.get("/", (req, resp) => {
    resp.send("Done")
    console.log("API called")
})

app.listen(8000)

Now we will see when we create so many API then we will check how many hit on particular API.

app.get("/", (req, resp) => {
    resp.send("Home page API")
    console.log("Home page API called")
})


app.get("/search", (req, resp) => {
    resp.send("Search API")
    console.log("Search API called")
})



app.get("/update", (req, resp) => {
    resp.send("update page API")
    console.log("update API called")
})

 Now we make a function that means it will keep updating the count of every hit we get on our API in the database.

const express = require("express");
const EventEmitter = require("events");
const app = express();

const event = new EventEmitter();
//this is object

let count = 0;

event.on("countAPI", () => {
  count++;
  console.log("Event called", count);
});

//first is the event name - countAPI
//second is the callback function



app.get("/", (req, resp) => {
  resp.send("Home page API");
  event.emit("countAPI"); 
});

app.get("/search", (req, resp) => {
  resp.send("Search API");
  event.emit("countAPI"); 
});
 
app.get("/update", (req, resp) => {
  resp.send("update page API");
  event.emit("countAPI");
});

app.listen(8000);

Disclaimer

upload the file from nodejs

This blog we have seen mongodb basic and how is it work with installation and after installation, we have already seen mongodb basic, CRUD operation, connect mongodb with nodejs, read, update, delete, POST, GET API etc. we should not face any problem while making Database, collection(table) and using the data in nodejs even whenever we will make API. Read data from mongodb in nodejs

• # What is OS module
• # Important functions of OS module

What is OS Module ?

In Node.js, the 'os' (operating system) module provides a set of methods to interact with the operating system. It allows you to access information about the system's resources, network interfaces, and other related details. Here are some commonly used functionalities provided by the OS module.

const os = require("os");
console.log(os.arch())

Returns a string identifying the operating system CPU architecture (e.g., 'x64').

const os = require("os");
console.log(os.freemem()/(1024*1024));
console.log(os.freemem()/(1024*1024*1024));

Returns the amount of free system memory in bytes. 

const os = require("os");

console.log(os.totalmem()/(1024*1024));
console.log(os.totalmem()/(1024*1024*1024));

Returns the total amount of system memory in bytes.

const os = require("os");

console.log(os.hostname());

Returns the host name of the operating system.

const os = require("os");

console.log(os.platform());

Returns a string identifying the operating system platform (e.g., 'darwin', 'win32', 'linux').

const os = require("os");

console.log(os.userInfo());

Disclaimer

upload the file from nodejs

This blog we have seen mongodb basic and how is it work with installation and after installation, we have already seen mongodb basic, CRUD operation, connect mongodb with nodejs, read, update, delete, POST, GET API etc. we should not face any problem while making Database, collection(table) and using the data in nodejs even whenever we will make API. Read data from mongodb in nodejs

• # What is Mongoose
• # Install Mongoose
  
• # Install Multer npm package
  
• # Make Router for upload file
  

Now in this blog  we will use mongoose. There is an npm package to connect nodes to mongodb. Mongoose is a MongoDB object modeling tool designed to work in an asynchronous environment. They created mongoose by improving mongodb, with the help of which you can create schemas and models of mongoose's movements.

Suppose that there are 4 fields in our database (like name, brand, price, category) and the user wants to add a 5th field also (like color) but we want to add only 4 fields, for this we create schemas.

Here you can also define TYPE in schemas like price type is numeric but if any user wants to use quotes (" " ' ') then we can stop the user for this.

in sort we can apply validation in mongoose but we can't in directly mongodb.

 What is MongoDB

MongoDB is a popular open-source NoSQL (non-relational) database management system. NoSQL means no structure like it is look like an object while in SQL it is a structure query language like SELECT CustomerName, City FROM Customers; (The SELECT statement is used to select data from a database.) But NoSQL database is useless...NOT completely because of whenever we want add extra column in database then it is possible through NoSQL MongoDB.   

MongoDB installation - CLICK HERE

MongoDB Basic Command - CLICK HERE

About MongoDB vs SQL - CLICK HERE

CRUD in MongoDB - CLICK HERE

Object Like - 

{
  "_id": {
    "$oid": "659ad46e0382148123c82841"
  },
  "name": "moto G60",
  "brand": "motorola",
  "price": 16500,
  "category": "mobile"
}

MongoDB is a type of database that helps store and manage large amounts of data in a flexible and scalable way. Unlike SQL, MongoDB doesn't require a fixed structure for the data, allowing you to store information in a more versatile format.

• MongoDB is a NoSQL database.
• The data stored in a collection
• Collection don't have row and columns
• Data is stored in the form of object.

Install Mongoose

For this you need to copy this (npm i mongoose) and paste it in project's terminal.

Install Multer npm package

First we need to install multer npm package in our project, if you want you can also write the code without this npm package. Let's first install it.

Simple go this link - CLICK HERE

CMD for installation - npm i multer

Make Router for upload file 

Now we will write code of upload file with the npm package multer but first we will send data POST method and using /upload endpoint and also you can create a folder named as uploads.

const express = require('express')
const multer = require('multer');
const app = express();


app.post("/upload" , (req, resp) => {
    resp.send("File uploaded")
});


app.listen(8000)

const upload = multer({
    storage: multer.diskStorage({
        destination:function(req, file, cb)
        {
            cb(null,'uploads/') //folder to save the files in 

        },
        filename:function(req, file, cb)
        {
           // cb(null, file.fieldname + "-" + Date.now() + ".jpg" )
            //if you can extract extension from  file then use this code
            var  ext=file.originalname.split(".");
            if(ext[ext.length-1]==='jpg' || ext[ext.length -1 ] === 'png'){
                cb(null , file.fieldname+ '-' +Date.now()+"."+ext[ext.length -1]);
            }else{
                cb(new Error('Error : Only jpg and png are allowed'));
        }
    }
    })
}).single("user_file");// field name in form data

 Let's breakdown the code.

1) Multer Configuration:

const upload = multer({
    storage: multer.diskStorage({
        // ... configuration options ...
    })
}).single("user_file");

# upload: This variable holds the configured multer middleware. It's set up to handle a single file upload.
# multer: This is the Multer middleware.
# storage: Multer's storage option defines how files should be stored. In this case, it uses multer.diskStorage to specify that files should be stored on the disk.


multer.diskStorage({
    destination: function(req, file, cb) {
        cb(null, 'uploads/');
    },
    filename: function(req, file, cb) {
        // ... filename configuration ...
    }
})




destination: A function that determines the destination folder for storing uploaded files. In this example, it's set to 'uploads/'. You need to make sure the 'uploads' directory exists in your project.

filename: A function that determines the name of the uploaded file. It checks the file extension and appends a timestamp to the original filename if it's a jpg or png file. If the file extension is not allowed, it throws an error.




3) Error Handling:


if (ext[ext.length - 1] === 'jpg' || ext[ext.length - 1] === 'png') {
    cb(null, file.fieldname + '-' + Date.now() + '.' + ext[ext.length - 1]);
} else {
    cb(new Error('Error: Only jpg and png are allowed'));
}




This part of the code checks the file extension. If the extension is 'jpg' or 'png', it generates a filename with the original fieldname, a timestamp, and the file extension. If the extension is not allowed, it invokes the callback with an error.


}).single("user_file");




The .single("user_file") part specifies that it's expecting a single file upload with the field name "user_file". The field name should match the one used in your HTML form's file input.

 Whole Code

const express = require('express')
const multer = require('multer');
const app = express();


const upload = multer({
    storage: multer.diskStorage({
        destination:function(req, file, cb)
        {
            cb(null,'uploads/') //folder to save the files in 

        },
        filename:function(req, file, cb)
        {
          
            var  ext=file.originalname.split(".");
            if(ext[ext.length-1]==='jpg' || ext[ext.length -1 ] === 'png'){
                cb(null , file.fieldname+ '-' +Date.now()+"."+ext[ext.length -1]);
            }else{
                cb(new Error('Error : Only jpg and png are allowed'));
        }
    }
    })
}).single("user_file");// field name in form data

app.post("/upload", upload , (req, resp) => {
    resp.send("File uploaded")
});


app.listen(8000)

Disclaimer

Search API with multiple filed in nodejs

This blog we have seen mongodb basic and how is it work with installation and after installation, we have already seen mongodb basic, CRUD operation, connect mongodb with nodejs, read, update, delete, POST, GET API etc. we should not face any problem while making Database, collection(table) and using the data in nodejs even whenever we will make API. Read data from mongodb in nodejs

• # What is Mongoose
• # Install Mongoose
  
• # Make Simple GET Route for API
  
• # Search with single field
  
• # Search with multiple fields
• # Test API 

Now in this blog  we will use mongoose. There is an npm package to connect nodes to mongodb. Mongoose is a MongoDB object modeling tool designed to work in an asynchronous environment. They created mongoose by improving mongodb, with the help of which you can create schemas and models of mongoose's movements.

Suppose that there are 4 fields in our database (like name, brand, price, category) and the user wants to add a 5th field also (like color) but we want to add only 4 fields, for this we create schemas.

Here you can also define TYPE in schemas like price type is numeric but if any user wants to use quotes (" " ' ') then we can stop the user for this.

in sort we can apply validation in mongoose but we can't in directly mongodb.

 What is MongoDB

MongoDB is a popular open-source NoSQL (non-relational) database management system. NoSQL means no structure like it is look like an object while in SQL it is a structure query language like SELECT CustomerName, City FROM Customers; (The SELECT statement is used to select data from a database.) But NoSQL database is useless...NOT completely because of whenever we want add extra column in database then it is possible through NoSQL MongoDB.   

MongoDB installation - CLICK HERE

MongoDB Basic Command - CLICK HERE

About MongoDB vs SQL - CLICK HERE

CRUD in MongoDB - CLICK HERE

Object Like - 

{
  "_id": {
    "$oid": "659ad46e0382148123c82841"
  },
  "name": "moto G60",
  "brand": "motorola",
  "price": 16500,
  "category": "mobile"
}

MongoDB is a type of database that helps store and manage large amounts of data in a flexible and scalable way. Unlike SQL, MongoDB doesn't require a fixed structure for the data, allowing you to store information in a more versatile format.

• MongoDB is a NoSQL database.
• The data stored in a collection
• Collection don't have row and columns
• Data is stored in the form of object.

Install Mongoose

For this you need to copy this (npm i mongoose) and paste it in project's terminal.

Make Simple GET Route for API

Here, we simple import express.js, configuration of mongodb file and schema file and express.json for converting into json format after getting output after that we create a /search route with /:key as a parameter. Then,  Product is our schema file and find method for all the data gaining from the mongodb.

const express = require('express');
require('./config')
const Product = require('./product')
const app = express();

app.use(express.json());


app.get('/search/:key', async (req, resp) => {
   console.log(req.params.key);
   let data = await Product.find()
   resp.send(data)
   //resp.send('Done')
})



app.listen(8000)

Run with nodemon index.js and after that we hit the request from postman.

Then we will search single data from single search 

app.get('/search/:key', async (req, resp) => {
   console.log(req.params.key);
   let data = await Product.find(
      {
         "$or": [
               { "name": {$regex: req.params.key}}
               ]
    }
   )
   resp.send(data)
   //resp.send('Done')
})

This code represents a route handler for an Express.js application. It defines an HTTP GET endpoint at the path '/search/:key'. The endpoint is designed to handle requests with a dynamic parameter ':key', which represents the search key or term.



Database Query Using Mongoose:


let data = await Product.find({ "$or": [{ "name": {$regex: req.params.key}}] });

This line uses the Mongoose library to query the MongoDB database. It searches for documents in the 'Product' collection where the 'name' field matches the provided search key using a case-insensitive regular expression.

Here's, only we are searched single search but after that we will create multiple search that's mean user search with value according to their demand like user search price's value, category, name, brand whatever users want.

 Search with multiple fields

   let data = await Product.find(
      {
         "$or": [
               { "name": {$regex: req.params.key}},
               { "brand": {$regex: req.params.key}}
               ]
    }
   )
   resp.send(data)
   
})

const express = require('express');
require('./config')
const Product = require('./product')
const app = express();

app.use(express.json());

app.get('/search/:key', async (req, resp) => {
   console.log(req.params.key);
   let data = await Product.find(
      {
         "$or": [
               { "name": {$regex: req.params.key}},
               { "brand": {$regex: req.params.key}}
               ]
    }
   )
   resp.send(data)
   //resp.send('Done')
})

app.listen(8000)

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