How do I check for login or other status before launching a route in Angular with routeProvider?

Question

Let's say I have 4 routes - 2 require the user to be logged in, 2 do not. My app init looks like:

        $routeProvider.when('/open1',{templateUrl:'/open1.html',controller:'Open1'});
        $routeProvider.when('/open2',{templateUrl:'/open2.html',controller:'Open2'});
        $routeProvider.when('/secure1',{templateUrl:'/secure1.html',controller:'Secure1'});
        $routeProvider.when('/secure2',{templateUrl:'/secure2.html',controller:'Secure2'});

Routes /open1 and /open2 are open to all, while routes /secure1 and /secure2 require the user to be logged in and, if not, take some action, e.g. redirect to login or launch a warning. I can determine the user's state by using my Auth service and calling, e.g., Auth.isLogin(). So the result would be:

• going to /open1 and /open2 always go to the template and controller declared above
• if Auth.isLogin() returns true, /secure1 and /secure2 go to the above-declared template and controller
• if Auth.isLogin() returns false, /secure1 and /secure2 take some other action, e.g. $location.path('/login')

I could put logic in the Secure1 and Secure2 controllers that checks, but that is repetitive and mixes up responsibilities, makes them harder to test, etc.

Is there a way that I can use the $routeProvider to declare, "check this route and this route and if not, redirect"? I was thinking of using resolve somehow, but not quite sure how to work it in (docs on resolve are not very clear, and few helpful examples).

EDIT:

based on the answers below, it appears there are three philosophies for doing this:

• Using resolve to check logged in and fail the promise, and then catching the $routeChangeError event to redirect http://www.sitepoint.com/implementing-authentication-angular-applications/
• Using just $routeChangeStart event to check logged in and redirect http://arthur.gonigberg.com/2013/06/29/angularjs-role-based-auth/
• Using just resolve to check logged in and redirect http://midgetontoes.com/blog/2014/08/31/angularjs-check-user-login

The 2nd option is what the two answerers have suggested.

Answer 1

As in my comments above, there are 3 different paths (plus the ability to use a directive if you want to control it from within html templates). I ended up following

https://midgetontoes.com/angularjs-check-user-login/

which essentially is as follows:

$routeProvider.when('/secure', {
    templateUrl: '/secure.html', 
    controller: 'Secure',
    resolve:{
        loggedIn:onlyLoggedIn
    }
 });

And then onlyLoggedIn:

var onlyLoggedIn = function ($location,$q,Auth) {
    var deferred = $q.defer();
    if (Auth.isLogin()) {
        deferred.resolve();
    } else {
        deferred.reject();
        $location.url('/login');
    }
    return deferred.promise;
};

Simple, works like a charm. If I ever need a directive, I will pull this piece into a service.