using $http in angular.js factory

All we need is an easy explanation of the problem, so here it is.

In my app I am using angular.js and jquery ui autocomplete. I had the same problem that is discussed
HERE
The accepted answer there works great for me and is exactly what I needed up until today when I need to replace the static array of values with an $http ajax call.
I tried to pass $http as parameter to the parent function but I get "Unknown provider: autoCompleteProvider <- autoComplete"

My question is, how can I use $http without rewriting or changing too much the current solution?

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

You need to add a callback reference in your getSource() function of your service:

app.factory('autoCompleteDataService', ['$http', function($http) {
   return {
       getSource: function(callback) {
          var url = '...';
          $http.get(url).success(function(data) {
             callback(data);
          }
       }
   }
}]);

You could also use $http.jsonp, if your server returns json. Don’t forget the JSON_CALLBACK parameter then.

In you directive you need to add the callback function itself:

...
autoCompleteDataService.getSource(function(data) {
   elem.autocomplete({
         source: data
         minLength: 2
   });    
});

Method 2

This is how you can do it:

app.factory('autoCompleteDataService', ['$http', function($http) {
    return {
        getSource: function() {
            return function(request, response) {
                $http.get(url).success(function(data) {
                    response(data);
                });
            }
        }
    }

}]);

However, if you want to download the entire data first and allow the autocomplete widget to search the data on the client side, this is an example how you can do it:

app.directive('autoComplete', function(autoCompleteDataService, $http) {
return {
    restrict : 'A',
    link : function(scope, elem, attr, ctrl) {
        autoCompleteDataService.getData(function(err, data) {
            if (err) {
                console.log("Could not retrieve data.");
                return;
            }

            elem.autocomplete({
                minLength: 0,
                source: data,
                focus: function( event, ui ) {
                    elem.val( ui.item.label );
                    return false;
                },
                select: function( event, ui ) {
                    elem.val( ui.item.label );
                    return false;
                }
            })
            .data( "ui-autocomplete" )._renderItem = function( ul, item ) {
                return $( "<li>" )
                .append( "<a>" + item.label + "</a>" )
                .appendTo( ul );
            };
        });
    }
};

});

app.factory('autoCompleteDataService', ['$http', '$rootScope', function($http, $scope) {
return {
    getData: function(callback) {
        if ($scope.data) {
            return callback(null, $scope.data);
        }

        $http.get('URL')
        .success(function(data) {
            $scope.data = data;
            return callback(null, data);
        })
        .error(function(data) {
            return callback(true, null);
        });
    }
}

}]);

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

Leave a Reply