Injection of dependencies in a filter function

Question

Injection of dependencies in a filter function

I'm writing a custom filter which depends on a constant object named config. This is what I've got so far:

angular.module('myproject.filters', []).filter('userLink', function () {
    return function (user) {
        return '';
    };
});

I need to inject the 'config' module into my filter so I can pull a static value out of it for building the link to a given user object.

How do I inject dependencies into filter functions?

angularjs
angularjs-filter

Answer 1

You can inject a service or a constant as a dependency like this

angular.module('myproject.filters', [])
    .filter('userLink', ['config', function (config) {
        return function (user) {
            if (user == null)
                return "#";

            return config.appRoot + '/user/' + user.id + "/";
        };
    }]);

If this depends on a config module like you mention, be sure to include that in your module statement.

Answer 2

You can inject dependencies into filters the same way you inject into controllers, services and factories.

angular.module('myproject.filters', ['config'])
.filter('userLink', ['$compile', '$timeout', 'configService', function ($compile, $timeout, configService) {
    return function (user) {
        return '';
    };
}]);

As eddiec pointed out if config is a module you must include it as a dependency for your myproject.filters. Then to include a service within the config module in the filter you inject it within the filter method.