{"id":13900,"date":"2016-07-14T16:15:11","date_gmt":"2016-07-14T13:15:11","guid":{"rendered":"http:\/\/www.webcodegeeks.com\/?p=13900"},"modified":"2018-01-09T10:49:06","modified_gmt":"2018-01-09T08:49:06","slug":"php-authentication-example","status":"publish","type":"post","link":"https:\/\/www.webcodegeeks.com\/php\/php-authentication-example\/","title":{"rendered":"PHP Authentication Example"},"content":{"rendered":"

In this example we are going to show you how to add an authentication system to your website. Authentication is an integral part of any web app that works with a login and registration system. Web apps like facebook.com, twitter.com and amazon.com use authentication to secure there users.<\/p>\n

Authentication is the process of determining whether someone or something is, in fact, who or what is declared to be. When you login into your facebook account, facebook has to be sure it is really you trying to login to your account and not an impostor. The process by which facebook guarantees that you really own the account (and not your evil twin), is authentication. Authentication has to be done correctly.
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\n[ulp id=’8njY7i2QRy6sg8pg’]
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\nIn this example we will develop a simple login and registration web app that shows the process of\u00a0authentication in php.
\nFor this example we will use:<\/p>\n

    \n
  1. A computer with PHP 5.5 installed<\/li>\n
  2. Mysql server<\/li>\n
  3. notepad++<\/li>\n
  4. Phpmyadmin: This is not compulsory. (All the codes in this example will work correctly even without it). If you want a graphical user interface for manipulating your datbase, then you should install it.<\/li>\n<\/ol>\n

    1. Getting Started<\/h2>\n

    If you are developing on your local machine, you can download and install wamp. Wamp installs both php, phpmyadmin and mysql on your local machine. Furthermore, wamp doesn’t require any specific prior knowledge to get it working.<\/p>\n

    1.1 Initializing the database<\/h2>\n

    This tutorial assumes you have php and mysql running. You should also create a database named authentication.<\/p>\n

    db.php<\/em><\/span><\/p>\n

     \r\n<?php\r\n$dsn = \"mysql:dbname=authentication\"; \r\n$username = \"root\"; \r\n$password = \"\"; \r\ntry{\r\n$conn = new PDO( $dsn, $username, $password );  \r\n$conn->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);\r\n}\r\ncatch(PDOException $pd){\r\necho $pd->getMessage();\r\n}\r\n?>\r\n\r\n<\/pre>\n
    This script creates a connection to the database. We are using PDO (Php data objects) to access our database. The connection is stored in the $conn<\/code> object and it is made available to manipulate the database.
    \nWe create a new PDO object in line 6 and surround it with a try\/catch statement, so as to catch any error that might occur while trying to connect to the database.<\/p>\n
    init.php<\/em><\/span><\/p>\n
     \r\n\r\n<?php\r\nrequire_once(\"db.php\");\r\ntry{\r\n$sql=\"create Table Myuser(id smallint  unsigned not null AUTO_INCREMENT PRIMARY KEY, name VARCHAR(265) NOT NULL,email VARCHAR(265)  NULL,password VARCHAR(265) NOT NULL)\";\r\n$conn->exec($sql);\r\necho \"TABLE CREATED\";\r\n}\r\ncatch(PDOException $pd){\r\necho \"Error Creating Table: \" . $pd->getMessage();\r\n}\r\n$conn=null;\/\/close the database connection\r\n?>\r\n\r\n<\/pre>\n
    Before you register\/login with the index.php script, you should load this script(init.php) into your browser (just once). The script creates a table that is called “Myuser” in the database. In line two we include the “db.php” script to login to the database. In line 5 we create a table in our database by calling the $conn->exec($sql)<\/code> method, which takes a string as a parameter (the string holds the sql query).<\/p>\n
    1.2 Authenticating users<\/h2>\n
    Here comes the interesting part. Let’s take a look at our login and register form.<\/p>\n
    index.php<\/em><\/span><\/p>\n
     \r\n<!DOCTYPE html> \r\n<html lang=en>\r\n\t<head>\r\n\t<style>\r\n\thtml, body{\r\n\twidth:100%;\r\n\theight:100%;\r\n\tmargin:0%;\r\n\tfont-family:\"helvetica\",\"verdana\",\"calibri\", \"san serif\";\r\n\toverflow:hidden;\r\n\tpadding:0%;\r\n\tborder:0%;\r\n\t}\r\n\t.a{\r\n\twidth:20%;\r\n\tmargin:10px;\r\n\theight:40px;\r\n\t}\r\n\t.a1{\r\n\tdisplay:inline;\r\n\twidth:20%;\r\n\theight:30px;\r\n\t\r\n\t}\r\n\t#sub{\r\n\tdisplay:inline;\r\n\t\r\n\t\r\n\t}\r\n\r\n\t<\/style>\r\n\t \t\t<meta charset=\"utf-8\" \/>\r\n\t\t<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no, target-densitydpi=device-dpi\"\/>\r\n\t\r\n\t<title><\/title>\r\n\t\r\n\t<\/head>\r\n\t<body>\r\n\r\n\t<h1>Login And Registration Form<\/h1>\r\n\t<div id=cen align=right>\r\n\t\r\n\t<form action=\"submit.php\" method=post>\r\n\t\r\n<input type=text class=a placeholder=name name=name required><br>\r\n\r\n<input type=email class=a placeholder=email name=email required><br>\r\n\r\n<input type=password class=a placeholder=Password name=password required><br>\r\n<input type=submit class=a value=Regster name=register>\r\n\r\n<\/form>\r\n<div align=right>\r\n\\\r\n\t \t<form action=\"submit.php\" method=post>\r\n <input type=email class=a placeholder=email required name=email><br>\r\n<input type=password class=a placeholder=password required name=password><br>\r\n<input type=submit class=a value=Login id=sub name=login>\r\n<\/form>\r\n\t\r\n\t<\/div>\r\n<\/div>\r\n\t<\/body>\r\n\t<\/html>\r\n\r\n<\/pre>\n
    This page contains the login and registration form. After a user fills the login or registration form and submit it, our php script “submit.php” is called.\u00a0We created a class called Database in the database.php script. This class contains the methods that perform authentication.<\/p>\n
    database.php<\/em><\/span><\/p>\n
    <?php\r\nrequire_once(\"db.php\");\r\n\r\nclass Database{\r\n\r\npublic function closeDataBase(){\r\n$conn=null;\r\n\r\n}\r\n\/* this checks if the user exists\r\n@param email is users email\r\n@param $conn is the connection object\r\n*\/\r\npublic function checkUserExist($email,$conn){\r\n$sql=\"select count(*) from Myuser where email=:email\";\r\n$st=$conn->prepare($sql);\r\n$st->bindValue(':email',$email);\r\n$st->execute();\r\n$num=$st->fetchColumn();\r\n$st=null;\r\nif($num>0)\r\nreturn true;\r\nelse \r\nreturn false;\r\n}\r\n\/*\r\nThis method authenticates the user\r\n@param email is users email\r\n@param password is the submitted password\r\n@param $conn is the connection object\r\n*\/\r\npublic function authen($email,$password,$conn){\r\n$sql=\"select password from Myuser where email=:email\";\r\n$st=$conn->prepare($sql);\r\n$st->bindValue(\":email\",$email);\r\n$res=$st->execute();\r\n$row=$st->fetchAll();\r\nif(password_verify($password,$row[0]['password']))\r\nreturn true;\r\nelse\r\nreturn false;\r\n}\r\n\r\npublic function register($email,$password,$name,$conn){\r\n$hash=password_hash($password,PASSWORD_DEFAULT);\/\/we hash  our password\r\n$sql=\"INSERT INTO Myuser ( email, password,name ) VALUES ( :email, :password ,:name)\"; \r\n$st=$conn->prepare($sql);\r\n$st->bindValue(\":email\",$email);\r\n$st->bindValue(\":password\",$hash);\r\n$st->bindValue(\":name\",$name);\r\n$st->execute();\r\n$st=null;\r\n}\r\n} \r\n?>\r\n\r\n<\/pre>\n
    The class database contains four important functions.<\/p>\n