In this tutorial, we will learn how to create a simple RESTful API for CRUD (Create, Read, Update, Delete) operations and the necessary HTTP Verbs. We will use functional programming approach in PHP

1. Project Structure

This is going to be the file structure of our project. Placed in location of the folder under "/var/www/html"

2. Database & Table Configuration

First we need to install MySQL database, if not Install Here.

Then we create a database, we can use phpMyAdmin or using the terminal. In this tutorial we are going to use terminal.

• Login to MySQL

• Create new database called "php_crud_api"

• Make use of the database

• Create table. 

Run the following script to create products table.

It will create products table with default of engine InnoDB

and you can verify using the following script

3. dbconfig.php

We will create a configuration file "dbconfig.php"  where we will store our database configurations we will use. 

<?php

$databaseHost = 'localhost';
$databaseUsername = 'root';
$databasePassword = 'xxxxxxxxxx';
$databaseName = 'php_crud_api';

$conn = mysqli_connect($databaseHost, $databaseUsername, $databasePassword, $databaseName);
if (!$conn){
    die("Database Connection Failed" . mysqli_error($conn));
}

4. create.php

create a file "create.php"  that will accept form inputs of "id, name, price" and store them in products table. 

<?php
    header('Content-Type: application/json')

    header('Access-Control-Allow-Methods: POST');

    include("dbconfig.php");
    $data = json_decode(file_get_contents('php://input'), true);

    $id = $data['id'];
    $name = $data['name'];
    $price = $data['price'];
    
    $CreateSql = "INSERT INTO products (product_id, product_name, product_price) VALUES ('$id', '$name', '$price')";
    $res = mysqli_query($conn, $CreateSql)  or die(mysqli_error($conn));
    if($res){
        $response = array("message"=>"Product inserted successfully", "status"=>true);
        echo json_encode($response, JSON_PRETTY_PRINT);
    }else{

        $response = array("message"=>"Failed to insert Product", "status"=>false);

        echo json_encode($response, JSON_PRETTY_PRINT);
    }


?>

we use Postman to create the products

we set HTTP VERB as "POST", and input we select raw and category "JSON". After inserting successfully you will be displayed with a success response as shown below

5. index.php

create a file "index.php"  that will read all records from the products table and display in JSON format.

<?php
header('Content-Type: application/json');

include("dbconfig.php");

$result = mysqli_query($conn, "SELECT * FROM products")  or die(mysqli_error($conn));

$row = mysqli_fetch_all($result, MYSQLI_ASSOC);

echo json_encode($row, JSON_PRETTY_PRINT);

?>

we use Postman to read the products

we set HTTP VERB as "GET", it will diplay array of product objects

6. update.php

create a file "update.php"  that will update one record based on product_id.

7. delete.php

create a file "delete.php"  that will delete one record based on product_id.