I'm an angular newby. I'm hoping to pass params to a service that fetches data form a server depending on those params. 
for example, if I want to pass a book name string and then use it in the service to concatenate with the request url. The documentation does not show clearly in this subject and I could not find helpful examples in other resources. 

**Let say, this is the controller:** 

```
app.controller('BookController', ['$scope', '$routeParams', 'books', function($scope, $routeParams, books) {
  // sending params to books service before a successful return 
  books.success(function(data) {
    $scope.book = data[$routeParams.bookId];
  });

```

**and this is the service** 

```
app.factory('books', ['$http', function($http) {
    // var url = 'http://...' + ParamFromController + '.json'
    return $http.get(url)
    .success(function(data) {
            return data;
    })
    .error(function(err) {
            return err; 
    });
}]);

```

So, how can I send params to 'books' service and then use it in the service? 
Thanks a lot in advance.