The Domain Host

The Domain class represents a domain name host component. Apart from the package common API and the host common API, the class exposes specific properties and methods to work with Domain name labels and logic.

If the modifications do not change the current object, it is returned as is, otherwise, a new modified object is returned.

If the submitted value is not valid a League\Uri\Exceptions\SyntaxError exception is thrown.

Partial or fully qualified domain name

A host is absolute or a fully qualified domain name (FQDN) if it contains a root label, its string representation ends with a ., otherwise it is known as being a relative or a partially qualified domain name (PQDN). The class allows use to get the domain name status and update it using the following feature

$host = Domain::new('');
$host->isAbsolute(); // return false

$fqdn = $host->withRootLabel(); //display ''
$fqdn->isAbsolute(); // return true

$pqdn = $fqdn->withoutRootLabel(); //display ''
$pqdn->isAbsolute(); // return false

Manipulating the domain name as an ordered list of labels

A domain is an ordered list of labels delimited by the host separator .. So it is possible to create a Domain object using a collection of labels with the Domain::fromLabels method. The method expects variadic of string or stringable objects representing the domain labels.

The labels must be ordered, this means that the top-level domain is the first entry


Since an IP is not a domain name, the class will throw an League\Uri\Exceptions\SyntaxError if you try to create a fully qualified domain name with a valid IP address.

echo Domain::fromLabels('com', 'example', 'shop');     //display ''
echo Domain::fromLabels('', 'com', 'example', 'shop'); //display '
Domain::fromLabels('0.1', '127.0'); //throws League\Uri\Exceptions\SyntaxError

The class implements PHP’s Countable and IteratorAggregate interfaces which means that you can count the number of labels and use the foreach construct to iterate overs them.

$host = Domain::fromLabels('com', 'example', 'shop'); //display ''
count($host); //return 3
foreach ($host as $offset => $label) {
    //do something meaningful here
[...Domain::new('')];  //return ['com', 'thephpleague', 'uri'];

Accessing the host labels and keys

Since we are manipulating the domain name as an ordered list we can use known methods to access the labels and their keys as with normal lists.


use League\Uri\Components\Domain;

$path = .Domain::new('');
$path->keys();          //return [0, 1, 2, 3];
$path->keys('www');     //return [3];
$path->keys('gweta');   //return [];
$path->get(0);          //return 'uk'
$path->get(23);         //return null
$path->get(-1);         //return 'www'
$path->get(-23);        //return null

keys always decode the submitted value to process the label data.

get always returns the decoded representation.

If the offset does not exist get will return null.

get supports negative offsets

Appending and Prepending labels

You can append or prepend labels to the current instance using the Domain::append and/or the Domain::prepend methods. Both method accepts a single argument which represents the data to be appended or prepended.

echo Domain::new('toto')->append(''); //return
echo Domain::new('')->prepend('toto'); //return

Replacing and removing labels

Replacing or removing labels is done on the basis of the label offsets by using the Domain::replaceLabel and/or the Domain::withoutLabels methods.

echo Domain::new('')->replaceLabel(2, 'bar.baz'); //return
echo Domain::new('')->withoutLabels(0, 2); //return example

replaceLabel and withoutLabels support negative offsets

if the specified offsets do not exist, no modification is performed and the current object is returned.