Hostname

Hostname

This constraint ensures that the given value is a valid host name (internally it uses the FILTER_VALIDATE_DOMAIN option of the filter_var PHP function).

New in version 5.1: The Hostname constraint was introduced in Symfony 5.1.

Applies to property or method
Options
Class Hostname
Validator HostnameValidator

Basic Usage

To use the Hostname validator, apply it to a property on an object that will contain a host name.

  • Annotations
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    // src/Entity/ServerSettings.php
    namespace App\Entity;
    
    use Symfony\Component\Validator\Constraints as Assert;
    
    class ServerSettings
    {
        /**
         * @Assert\Hostname(message="The server name must be a valid hostname.")
         */
        protected $name;
    }
    
  • YAML
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    # config/validator/validation.yaml
    App\Entity\ServerSettings:
        properties:
            name:
                - Hostname:
                    message: The server name must be a valid hostname.
    
  • XML
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    <!-- config/validator/validation.xml -->
    <?xml version="1.0" encoding="UTF-8" ?>
    <constraint-mapping xmlns="http://symfony.com/schema/dic/constraint-mapping"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://symfony.com/schema/dic/constraint-mapping https://symfony.com/schema/dic/constraint-mapping/constraint-mapping-1.0.xsd">
    
        <class name="App\Entity\ServerSettings">
            <property name="name">
                <constraint name="Hostname">
                    <option name="message">The server name must be a valid hostname.</option>
                </constraint>
            </property>
        </class>
    </constraint-mapping>
    
  • PHP
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    // src/Entity/ServerSettings.php
    namespace App\Entity;
    
    use Symfony\Component\Validator\Constraints as Assert;
    use Symfony\Component\Validator\Mapping\ClassMetadata;
    
    class ServerSettings
    {
        public static function loadValidatorMetadata(ClassMetadata $metadata)
        {
            $metadata->addPropertyConstraint('name', new Assert\Hostname([
                'message' => 'The server name must be a valid hostname.',
            ]));
        }
    }
    

The following top-level domains (TLD) are reserved according to RFC 2606 and that's why hostnames containing them are not considered valid: .example, .invalid, .localhost, and .test.

Note

As with most of the other constraints, null and empty strings are considered valid values. This is to allow them to be optional values. If the value is mandatory, a common solution is to combine this constraint with NotBlank.

Options

groups

type: array | string

It defines the validation group or groups this constraint belongs to. Read more about validation groups.

message

type: string default: This value is not a valid hostname.

The default message supplied when the value is not a valid hostname.

You can use the following parameters in this message:

Parameter Description
{{ value }} The current (invalid) value

payload

type: mixed default: null

This option can be used to attach arbitrary domain-specific data to a constraint. The configured payload is not used by the Validator component, but its processing is completely up to you.

For example, you may want to use several error levels to present failed constraints differently in the front-end depending on the severity of the error.

requireTld

type: bool default: true

By default, hostnames are considered valid only when they are fully qualified and include their TLDs (top-level domain names). For instance, example.com is valid but example is not.

Set this option to false to not require any TLD in the hostnames.

Note

This constraint does not validate that the given TLD value is included in the list of official top-level domains (because that list is growing continuously and it's hard to keep track of it).

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.