Laravel路由：如何在URI中添加可选参数？

Question

Realising a API Rest service I'm facing the problem of how/where in the url signature pass the API version.

By reading around I decided to pass the version like

http://mydomainservice.tld/api/version/entity ...

About treat version as optional and parse the request referring to as latest API version, this would be the intention:

http://mydomainservice.tld/version/entity ...

The question is not about how to manage/arrange versioning in API rest but more if there's the chance to realise a routing rule to prepend a optional parameter in the URI:

This is working:

Route::group(['prefix' => 'api/'], function(){
  Route::get('{v}/subscribers', 'APIRequestController@show');
  Route::get('subscribers', 'APIRequestController@show);
});

For both calls like:

http://mydomain.tld/api/subscribers http://mydomain.tld/api/1/subscribers

But I'd like to solve it in a single rule:

Route::get('{v?}/subscribers', 'APIRequestController@show');

But this second rule won't work by itself if i try to reach out with a request like:

http://mydomain.tld/api/subscribers

Answer 1

This is not possible to do cleanly . Every route parameter requires some kind of value, it can be null when it in the end of URL, but not in a middle of URL.

Despite that, there is super dirty solution: Route::get('{v}subscribers', 'APIRequestController@show')->where('v', '([0-9/]+)?');

Now You can access "yourdomain/api/1/subscribers" as well as "yourdomain/api/subscribers", but make sure You have default value for that v parameter in Your controller. And also You have cut that slash which comes with parameter.

And finally: don't do this, better write two separate lines and keep code as clean as possibly, than do this kind of magic.