Create Rest API in PHP

I’m the author of InderCodes and I want to share the core of the application with you.

I’ll explain you the CURD operation via API for one complete module.

PROJECT CODE AVAILABLE ON GITHUB:

You need to create two files to test the project:

1. database.php
2. user.php

 

database.php  contains below code:

<?php

//********** Database Connections **************//
//MySqli Driver used

$mysql_host = “localhost”;
$username = “root”;
$password = “”;
$mysql_database = “php_api”;

$con = mysqli_connect($mysql_host, $username, $password, $mysql_database);

// Check connection
if (mysqli_connect_errno()) {
echo “Failed to connect to MySQL: ” . mysqli_connect_error();
}

This file we’ve used to connect with our MySQL database. In the demo project I’ve created php_api database.

php_api databse contain one table users. You can use the below SQL Script to create the same.

— Table structure for table `users`
—

CREATE TABLE `users` (
`id` int(11) NOT NULL,
`first_name` varchar(50) NOT NULL,
`last_name` varchar(50) NOT NULL,
`email` varchar(50) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

INSERT INTO `users` (`id`, `first_name`, `last_name`, `email`) VALUES
(1, ‘Steve’, ‘Jobs’, ‘steve@apple.com’);

ALTER TABLE `users`
ADD PRIMARY KEY (`id`);

—
— AUTO_INCREMENT for dumped tables
—

—
— AUTO_INCREMENT for table `users`
—
ALTER TABLE `users`
MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=2;

To test the API i recommend to use Postman.

After creating database we have new users.php file

users.php

<?php

include(“Database.php”);

switch ($_GET[‘function’]) {
case ‘users_list’: users_list();
break;
case ‘add_user’: add_user();
break;
case ‘edit_user’: edit_user();
break;
case ‘delete_user’: delete_user();
break;
}

 

//http://localhost/php_api/users.php?function=users_list
function users_list() {

//Accessing Connection details by using Global variable
$db = $GLOBALS[‘con’];

$sql = “SELECT id, first_name, last_name FROM users;”;

if ($result = mysqli_query($db, $sql)) {
if (mysqli_num_rows($result) > 0) {
while ($row = mysqli_fetch_array($result)) {

$rows[] = array(‘data’ => $row);
}
mysqli_free_result($result);

$json_op = array(
“status_code” => 101,
“msg” => “Users List successfully displayed.”,
“users_list” => $rows
);
} else {

$json_op = array(
“status_code” => 102,
“msg” => “No User available.”,
“event_list” => []
);
}

@mysqli_close($db);
/* Output header */
header(‘Content-type: application/json’);
echo json_encode($json_op);
}
}

//http://localhost/php_api/users.php?function=add_user
/*
Need to pass three parameter via POST
1. first_name
2. last_name
3. email
*/
function add_user() {

$first_name = $_POST[‘first_name’];
$last_name = $_POST[‘last_name’];
$email = $_POST[’email’];

//Validating required fields
if (!empty($first_name) || !empty($email)) {
$db = $GLOBALS[‘con’];

$sql = “INSERT INTO users (first_name, last_name, email)
VALUES (‘$first_name’,’$last_name’, ‘$email’);”;

if (mysqli_query($db, $sql)) {
$json_op = array(
“status_code” => 103,
“msg” => “User added successfully.”
);
} else {
$json_op = array(
“status_code” => 104,
“error” => $db->error,
“msg” => “Event failed to add.”
);
}

@mysqli_close($db);
/* Output header */
header(‘Content-type: application/json’);
echo json_encode($json_op);
}
}

//http://localhost/php_api/users.php?function=edit_user
/*
Need to pass id parameter via POST with all other 3 parameters
id parameter will identify the row to update

1. id
2. first_name
3. last_name
4. email

*/
function edit_user() {

$id = $_POST[‘id’];
$first_name = $_POST[‘first_name’];
$last_name = $_POST[‘last_name’];
$email = $_POST[’email’];

if (!empty($id) || !empty($first_name) || !empty($email)) {
$db = $GLOBALS[‘con’];

$sql = “UPDATE users SET first_name = ‘$first_name’,
last_name = ‘$last_name’, email = ‘$email’
WHERE id = ‘$id’;”;

if (mysqli_query($db, $sql)) {
$json_op = array(
“status_code” => 105,
“msg” => “User updated successfully.”
);
} else {
$json_op = array(
“status_code” => 106,
“error” => $db->error,
“msg” => “User failed to update.”
);
}

@mysqli_close($db);
/* Output header */
header(‘Content-type: application/json’);
echo json_encode($json_op);
}
}

//http://localhost/php_api/users.php?function=delete_user
/*
Need to pass id parameter via POST
*/
function delete_user() {

$id = $_POST[‘id’];

if (!empty($id)) {
$db = $GLOBALS[‘con’];

$sql = “DELETE FROM users WHERE id = $id;”;

if (mysqli_query($db, $sql)) {
$json_op = array(
“status_code” => 107,
“msg” => “User deleted successfully.”
);
} else {
$json_op = array(
“status_code” => 108,
“error” => $db->error,
“msg” => “User failed to delete.”
);
}

@mysqli_close($db);
/* Output header */
header(‘Content-type: application/json’);
echo json_encode($json_op);
}
}

In the above file we’ve four functions:

1. users_list
2. add_user
3. edit_user
4. delete_user

Use POST method to pass any parameter from API.

You can access the API by below URL’s:

1. http://localhost/php_api/users.php?function=users_list
2.        http://localhost/php_api/users.php?function=add_user (need to pass 3 parameters: first_name, last_name, email)
3.        http://localhost/php_api/users.php?function=edit_user (need to pass 4 parameters: id, first_name, last_name, email)
4.        http://localhost/php_api/users.php?function=delete_user (need to pass 1 parameter: id)

 

OUTPUT : users_list

{
“status_code“: 101,
“msg“: “Users List successfully displayed.“,
“users_list“: [
{
“data”:

{
  “0”: “1”,
  “1”: “Steve”,
  “2”: “Jobs”,
  “id”: “1”,
  “first_name”: “Steve”,
  “last_name”: “Jobs”
}
}
]
}

Status Code: It works as a error code which helps you to track the API failure status.

msg: It print the success/failure message

Remaining all are the data returned by API in JSON format.

 

Thanks & Regards,

Inderjeet Singh