The Route from $_GET to String

The global arrays in PHP contain request parameters. Either GET or POST. As you know if the page address is something like:

http://www.example.com/index.php?a=b&key=value

This means that you pass to the index.php file two parameters – “a” and “key” with their values: “b” and “value”. Now in this case you can dump the $_GET global array somewhere in index.php and you’ll receive something like this.

array(
	"a"   => "b",
	"key" => "value",
);

This is however pseudocode, but in fact $_GET will be very similar to this sample array.

$_GET to String

Very often when a developer need to process the $_GET array to a string, which means generating again the query string from $_GET, he often comes to some operation like this one.

$queryString = '';
foreach ($_GET as $key => $value) {
	$queryString .= $key . '=' . $value . '&';
}

However this will result in something quite ugly like a=b&key=value& which comes with a trailing & at the end of the string.

There is however another approach – using an array.

$queryString = array();
foreach ($_GET as $key => $value) {
	$queryString[] = $key . '=' . $value;
}
$queryString = implode('&', $queryString);

But that invokes one function more and this is still not the most elegant solution. As I said at the beginning PHP is full of useful functions and here comes the http_build_query.

http_build_query

This is exactly what you need. As it name describe you can build the query string even by using a different from & separator.

$queryString = http_build_query($_GET, '', '|');

Thus $queryString will contain a=b|key=value and at least the code will look pritier.

This is important because the header is changed and if something goes after the redirect there will be some problems. Finally the correct snippet is:

public function() {
	$this->_redirect('some_url');
	exit();	
}

$this->_redirect('/url/return-to/1');

Once this parameter is processed by the controller/action you can return to the referrer!

First of all what’s a link shortener? Such online software exists and it’s widely used by the customers. Sites like bit.ly became extremely popular because of the growth of web apps like Facebook and especially Twitter. The simple goal that they achieve is to convert a long website uri into a short unique one. Beside that they give more information about who clicked that link and some useful stats along with that.

The question is why to make your own link shortener? One of the main reasons why is to paste links containing in plaintext your domain. In the case of http://stoimen.com/ instead of using http://bit.ly/xxxxx it will be great if the link was something like http://stoimen.com/xxxx than pasting it into Twitter or wherever I get the primary impression of my domain.

How to …

It should be no mystery how to make your own. In fact you’ll need only one more table into the database, as this is the most common way to achieve it. Of course you can do that with no database using the file system to store the hash table in whatever format you’d like.

In the case of the DB solution you can simply make a table with three columns containing the unique id of the row, the short and the full link. Thus requesting some short link the db will return the “real” full uri. You can simply drop the short column if you’d like more efficient solution. Thus the unique identifier may become short link. That may be really fast if you’ve an index on the full link column.

See the example below:

id | short_link | full_link
1  | qwrt 	| /blog/2010/01/27/theory-of-caching-zend_cache-zend-optimizer