The Host

The Host class represents a generic host component. Apart from the package common API the class exposes basic properties and method to manipulate any type of host whether it is a registered name or an IP address.

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.

Host types

If you don’t have an IP then you are dealing with a registered name. A registered name can be a domain name subset if it follows RFC1123, but it is not a requirement as stated in RFC3986

(…) URI producers should use names that conform to the DNS syntax, even when use of DNS is not immediately apparent, and should limit these names to no more than 255 characters in length.

As such to expose the correct type, the Host object uses 3 methods isRegisteredName, isDomain and isIp.

$domain = Host::new('www.example.co.uk');
$domain->isRegisteredName();  //return true
$domain->isDomain();          //return true
$domain->isIp();              //return false

$ipAddress = Host::new('127.0.0.1');
$ipAddress->isRegisteredName();  //return false
$ipAddress->isDomain();          //return false
$ipAddress->isIp();              //return true

$registeredName = Host::new('...test.com');
$registeredName->isRegisteredName();  //return true
$registeredName->isDomain();          //return false
$registeredName->isIp();              //return false

Normalization

Whenever you create a new host your submitted data is normalized using non-destructive operations:

the host is lower-cased;
the host is converted to its ascii representation;

echo Host::new('ShOp.ExAmPle.COM')->value(); //display 'shop.example.com'
echo Host::fromUri('https://BéBé.be')->toString(); //display 'xn--bb-bjab.be'

The last example depends on the presence of the ext-intl extension, otherwise the code will trigger a MissingFeature exception

At any given time you can access the ascii or unicode Host representation using the two (2) following methods:

$host = Host::new('BéBé.be');
echo $host; //display 'xn--bb-bjab.be'
echo $host->toUnicode();  //displays bébé.be
echo $host->toAscii();    //displays 'xn--bb-bjab.be'

Host as IP address

public static Host::fromIp(string $ip, string $version = ''): self
public Host::isIpv4(): bool
public Host::isIpv6(): bool
public Host::isIpFuture(): bool
public Host::hasZoneIdentifier(): bool
public Host::withoutZoneIdentifier(): self

Host::fromIp

This method allows creating a Host object from an IP.

$ipv4 = Host::fromIp('127.0.0.1');
echo $ipv4; //display '127.0.0.1'

$ipv6 = Host::fromIp('::1');
echo $ipv6; //display '[::1]'

Host::fromIp('uri.thephpleague.com');
//throws League\Uri\Exceptions\SyntaxError

The method can also infer the IPv4 from its hexadecimal or octal representation. Behind the scene This normalization works using WHATWG IPv4 host parsing rules via the League\Uri\Ipv4\Converter class

A RuntimeException will be trigger if the conversion can not be done due to a lack of supported PHP extension.

echo Host::fromIp('999999999'); //display '59.154.201.255'
//will work on supported platform 

This normalization is destructive and thus is never apply internally on a instantiated Host object.

IPv4 or IPv6

There are two (2) types of host:

Hosts represented by an IP;
Hosts represented by a registered name;

To determine what type of host you are dealing with the Host class provides the isIp method:

$host = Host::new('example.com');
$host->isIp(); //return false;
$ip_host = Host::new('127.0.0.1');
$ip_host->isIp(); //return true;

Knowing that you are dealing with an IP is good, knowing its version is better.

$ipv6 = Host::fromIp('::1');
$ipv6->isIp();         //return true
$ipv6->isIpv4();       //return false
$ipv6->isIpv6();       //return true
$ipv6->isIpFuture();   //return false
$ipv6->getIpVersion(); //return '6'

$ipv4 = Host::new('127.0.0.1');
$ipv4->isIp();         //return true
$ipv4->isIpv4();       //return true
$ipv4->isIpv6();       //return false
$ipv4->isIpFuture();   //return false
$ipv4->getIpVersion(); //return '4'

$ipfuture = Host::new('v32.1.2.3.4');
$ipfuture->isIp();         //return true
$ipfuture->isIpv4();       //return false
$ipfuture->isIpv6();       //return false
$ipfuture->isIpFuture();   //return true
$ipfuture->getIpVersion(); //return '32'

$domain = Host::new('thephpleague.com'):
$domain->isIp();         //return false
$domain->isIpv4();       //return false
$domain->isIpv6();       //return false
$domain->isIpFuture();   //return false
$domain->getIpVersion(); //return null

Zone Identifier

Detecting the presence of the Zone Identifier

The object can also detect if the IPv6 has a zone identifier or not. This can be handy if you want to know if you need to remove it or not for security reason.

$ipv6 = Host::new('[Fe80::4432:34d6:e6e6:b122%eth0-1]');
$ipv6->hasZoneIdentifier(); //return true

$ipv4 = Host::new('127.0.0.1');
$ipv4->hasZoneIdentifier(); //return false

Removing the Zone Identifier

According to RFC6874:

You must remove any ZoneID attached to an outgoing URI, as it has only local significance at the sending host.

To fulfill this requirement, the Host::withoutZoneIdentifier method is provided. The method takes not parameter and return a new host instance without its zone identifier. If the host has not zone identifier, the current instance is returned unchanged.

$host    = Host::new('[fe80::1%25eth0-1]');
$newHost = $host->withoutZoneIdentifier();
echo $newHost; //displays '[fe80::1]';

Getting the IP string representation

You can retrieve the IP string representation from the Host object using the getIp method. If the Host is not an IP null will be returned instead.

$host = Host::new('[fe80::1%25eth0-1]');
$host->getIp(); //returns 'fe80::1%eth0-1'

$newHost = Host::new('uri.thephpleague.com');
$newHost->getIp();        //returns null
$newHost->getIpVersion(); //returns null