Description
Be able to configure host per locale in the same way that we can configure prefix per locale.
Thus we will be able to indicate that the

• url beginning with www.website.es matches the locale es (spanish)
• url beginning with www.website.be/nl/ matches the locale is nl_BE (dutch of BELGIUM)

History
Prefix/path per locale is possibe from Symfony 4.1. Development has been done in that PR.

Vocabulary used
In www.website.be/nl/offers/index.html :

• host: www.website.be
• path-prefix: /nl (can be also named path/folder/directory/prefix)
• full-prefix: www.website.be/nl (host + path-prefix = full-prefix)

Configuration
Below are 2 examples of how to configure that, can we agree with one and how it will work ?

1. Host + path-prefix in same configuration
   Set both the host and path-prefix (full-prefix) :

site:
    resource: '../src/Controller/'
    prefix:
        en: '/site'
        es: '://www.website.es'
        nl_BE: '://www.website.be/nl/'
    type: annotation

That above code without es: '://www.website.es' row and ://www.website.be is working in Symfony 4.1

Note that we are using :// to be able to detect later that the configuration is using a full-prefix and not only a prefix-path.

Questions:

• Must it begin with :// or // ?
• Extract host from configuration :
  • starts with ":// => it's a full-prefix (host + path-prefix)
  • otherwise => it's only a path prefix
  • in the really specific case that we want to have the following url possible www.website.com/://www.website.com/site/index.html only specifying the path-prefix the conf will be

[...]
    prefix:
        en: '/://www.website.com/site'

• Others solutions to detect that the conf starts with a host ?
  • regex?
  • the conf can only starts with
    • "/" for a path-prefix
    • "://" for a host or full-prefix
    • otherwise, it throws a configuration error
• What happens when the host is also on the non locale level ? (Eg: @Route(host="www.website.com") or host: www.website.com)
• Should we rename prefix:?
• In the above configuration what happens if url starts with www.website.es/site ? Throws a configuration error ? Thus mixing configurations will be possible if there is no "host" only configuration.

2. Host in separate configuration

site:
    resource: '../src/Controller/'
    prefix:
        en: '/site'
        es: '/sitio'
    host:
        es: 'www.website.es'
    type: annotation

Questions:

• What happens when both the locale host and non locale host are set ? Use the 1. locale host - 2. non locale host - 3. Throws an exception

Quick code to implement the feature with 1) conf :
YAMLFileLoader:197

const URL_KEY = '://';
//if the it starts with ://
if (substr($localePrefix, 0, strlen(self::URL_KEY)) === self::URL_KEY) {
  $posFirstSlash = strpos($localePrefix, '/', strlen(self::URL_KEY));
  $localeHost = substr($localePrefix, strlen(self::URL_KEY), $posFirstSlash-strlen(self::URL_KEY));
  $localePrefix = substr($localePrefix, $posFirstSlash);
  $localizedRoute->setHost($localeHost);
}

Related with :

• [Routing] Implement i18n routing #26143
• https://symfony.com/doc/current/routing/hostname_pattern.html
• https://github.com/remmel/JMSI18nRoutingBundle