Author: dreboard

PHP: get_called_class vs get_class

get_called_class vs get_class

string get_called_class ( void ) //  Gets the name of the class the static method is called in. 
string get_class ([ object $object = NULL ] ) // Gets the name of the class of the given object. 


-------- get_called_class
class foo {
    static public function test() {
        var_dump(get_called_class());
    }
}

class bar extends foo {
}

foo::test(); // string(3) "foo"
bar::test(); // string(3) "bar"

--------- get_class

• get_class($this)
• get_class($bar)

class foo {
    function name()
    {
        echo "My name is " , get_class($this) , "\n";
    }
}

$bar = new foo(); // create an object
echo "Its name is " , get_class($bar) , "\n"; // external call		// Its name is foo
$bar->name(); // internal call						// My name is foo

----------

abstract class bar {
    public function __construct()
    {
        var_dump(get_class($this));
        var_dump(get_class());
    }
}

class foo extends bar {
}

new foo;

string(3) "foo"
string(3) "bar"

PHP Errors and Logging Settings

PHP .ini file

Locate the section “Error handling and logging”, This directive informs PHP of which errors, warnings and notices you would like it to take action for.

You will see and be able to alter these config settings

error_reporting = E_ALL
display_errors = On
display_startup_errors = On
log_errors = On
log_errors_max_len = 1024
ignore_repeated_errors = Off
ignore_repeated_source = Off
report_memleaks = On
track_errors = Off
html_errors = On
Error Reporting

This directive informs PHP of which errors, warnings and notices you would like it to take action for.

To show only errors, (no warnings or notices)

error_reporting = E_COMPILE_ERROR|E_RECOVERABLE_ERROR|E_ERROR|E_CORE_ERROR

If you do only display errors, you will not be able to see common run time notices and warnings such as

NOTICE Undefined variable: var on line number 2

Display Errors

Just because error reporting is turned on, you wont be able to see the errors unless the display_errors flag has the on value

To show only errors, (no warnings or notices)

display_errors = On

Prevent Files from being cached

Using php
<link href="/stylesheet.css?<?php echo time(); ?>" rel="stylesheet" type="text/css" />
<script type="text/javascript" src="/site-script.js?<?php echo time(); ?>"></script>

// OR
<link href="/stylesheet.css?<?php echo filemtime('mycss.css'); ?>" rel="stylesheet" type="text/css" />

// OR
/**
 *  Given a file, /css/base.css, replaces it with a string containing the
 *  file's mtime, /css/base.1221534296.css.
 *  
 *  @param $file  The file to be loaded.  Must be an absolute path
 */
function auto_version($file)
{
  if(strpos($file, '/') !== 0 || !file_exists($_SERVER['DOCUMENT_ROOT'] . $file))
    return $file;

  $mtime = filemtime($_SERVER['DOCUMENT_ROOT'] . $file);
  return preg_replace('{\\.([^./]+)$}', ".$mtime.\$1", $file);
}

<link rel="stylesheet" href="/css/base.css" type="text/css" />




// OR


// OR
/**
 *  Given a file, /css/base.css, replaces it with a string containing the
 *  file's mtime, /css/base.1221534296.css.
 *  
 *  @param $file  The file to be loaded.  Must be an absolute path
 */
function auto_version($file)
{
  if(strpos($file, '/') !== 0 || !file_exists($_SERVER['DOCUMENT_ROOT'] . $file))
    return $file;

  $mtime = filemtime($_SERVER['DOCUMENT_ROOT'] . $file);
  return preg_replace('{\\.([^./]+)$}', ".$mtime.\$1", $file);
}
Using javascript
Using .htaccess


  FileETag None
    
      Header unset ETag
      Header set Cache-Control "max-age=0, no-cache, no-store, must-revalidate"
      Header set Pragma "no-cache"
      Header set Expires "Wed, 11 Jan 1984 05:00:00 GMT"
Using GIT

/**
 * Get the hash of the current git HEAD
 * @param str $branch The git branch to check
 * @return mixed Either the hash or a boolean false
 */
public static function get_commit( $branch='master' ) {
  if ( $hash = file_get_contents( sprintf( '.git/refs/heads/%s', $branch ) ) ) {
    return $hash;
  } else {
    return time();
  }
}

Slim 3 PHP Routes Return 404 Page Not Found

If your routes give you a 404 error when removing the localhost:8080/index.php/xxx

Ensure that your 000-default.conf or whatever you name it has AllowOverride All


    ServerAdmin webmaster@localhost
    DocumentRoot /var/www/html/public

    ServerName "dev.local"
    ServerAlias "www.dev.local"

    
        Options -Indexes +FollowSymLinks +MultiViews
        AllowOverride All
        Require all granted
    
    # Possible values include: debug, info, notice, warn, error, crit,
    # alert, emerg.
    LogLevel warn
    ErrorLog /var/www/html/logs/error.log
    CustomLog /var/www/html/logs/access.log combined

Ensure that a .htaccess file is in the same folder as the index.php, and the contents are


    RewriteEngine On
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule ^ index.php [qsappend,last]

Restart/reload apache apache

sudo service apache2 reload
service apache2 restart
service httpd reload
//For whatever flavor your running

Create a MySQL users Table

Code for Creating `users` Table inside PhpMyAdmin


CREATE TABLE `users` (
  `id` int NOT NULL AUTO_INCREMENT,
  `employee_id` int DEFAULT NULL,
  `user_type` varchar(50) DEFAULT NULL,
  `username` varchar(100) NOT NULL,
  `password` varchar(100) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `users` (`employee_id`, `user_type`, `username`, `password`) VALUES
                   (NULL, 'SUPER ADMIN', 'admin', 'admin'),
                   (1, 'NORMAL', 'robin', 'robin'),
                   (2, 'ADMIN', 'taylor', 'taylor'),
                   (3, 'ADMIN', 'vivian', 'vivian'),
                   (4, 'NORMAL', 'harry', 'harry'),
                   (7, 'ADMIN', 'melinda', 'melinda'),
                   (8, 'NORMAL', 'harley', 'harley');

Command line code for Creating `user` from a users.sql file


mysql> use db_name;
mysql> source users.sql;

Slim 3 API Part 2 DB Configurations

Database configuration

Create the file src/settings.php inside your api folder and place the following code


        "db" => [
            "host" => "locahost",
            "dbname" => "your-database-name",
            "user" => "your-mysql-user",
            "pass" => "your-mysql-password"
        ],

Create the file src/dependencies.php inside your api folder and place the following code


$container['db'] = function ($c) {
    $settings = $c->get('settings')['db']; // From src/settings.php
    $pdo = new PDO("mysql:host=" . $settings['host'] . ";dbname=" . $settings['dbname'],
        $settings['user'], $settings['pass']);
    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    $pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
    return $pdo;
};

This is injecting the database object into container, and you can now access all users
** For creating the users table see Create users table post


require __DIR__ . '/vendor/autoload.php';
$app = new Slim\App;

$app->get('/', function ($request, $response) {
    return 'hello world';
});

 $app->post('/postit', function ($request, $response) {
     $input = $request->getParsedBody();
     return $this->response->withJson($input);
 });

 $app->get('/all', function ($request, $response, $args) {
 $sth = $this->db->prepare("SELECT * FROM users");
 $sth->execute();
 $users = $sth->fetchAll();
     return $this->response->withJson($users);
 });

$app->run();

Slim 3 API Part 1 Hello World

Installation

1. Create your api folder
2. Make sure you download the composer.phar file into the folder.
3. Open a shell script, cd to your new api folder and type

composer require slim/slim "^3.0"
//or
php composer.phar require slim/slim "^3.0"

Basic Setup and Routing

Now you should only see your composer.lock, composer.json and a vendor directory. Create index.php and place the following code inside.

get('/', function ($request, $response) {
    return 'hello world';
});

$app->run();

Preview

Go back to the terminal and type

php -S localhost:8000

in the browser visit, http://localhost:8000/ you should see “hello world”

API calls with Slim

GET is used for reading and retrieving data.
POST is used for inserting data.
PUT is used for updating data.
DELETE is used for deleting data.

POST

get('/', function ($request, $response) {
    return 'hello world';
});

 $app->post('/postit', function ($request, $response) {
     $input = $request->getParsedBody();
     return $this->response->withJson($input);
 });

$app->run();

You can then create a form but we will simulate a form post by using curl.
on the command line run

curl -d "param1=value1¶m2=value2" -X POST http://localhost:8000/postit

You should see

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100    64  100    37  100    27     45     33 --:--:-- --:--:-- --:--:--    78{"param1":"value1","param2":"value2"}

Track number of objects created from a class

To track the existing number of objects of a given class create a static property to hold the current value, updated with the constructor. When unsetting an object, the __destruct() method will update the object count. You can create new instances without hitting the constructor via clone and deleted with unset()


/*
* Class TrackableClass 
*/
class TrackableClass {
    public static $instances = 0;

    public function __construct() 
    {
        self::$instances++;
    }

    public function __destruct() 
    {
        self::$instances--;
    }
	
    public function __clone() 
    {
	self::$instances++;
    }
	
    public function __unset($name)
    {
        self::$instances--;
    }
	
}

$obj1 = new TrackableClass();
$obj2 = new TrackableClass();
$obj3 = new TrackableClass();
$obj4 = clone $obj3;

echo TrackableClass::$instances; // 4
unset($obj4);
echo TrackableClass::$instances; // 3
$obj3 = null;
echo TrackableClass::$instances; // 2