angular dynamic resource manager

res_service.js

angular.module('app').service('Res', ['$rootScope', function ($rootScope) {
    var scope = $rootScope
    scope._scripts = scope._scripts || []
    scope._styles = scope._styles || []
    scope._rawScripts = scope._rawScripts || []
    scope._rawStyles = scope._rawStyles || []

    return {
        style: function (inp) {
            var hrefs = []
            if (typeof inp === 'string') {
                hrefs.push(inp)
            } else {
                hrefs = inp
            }

            scope._styles = []
            for (var i in hrefs) {
                console.log('styling page with ' + hrefs[i])
                var style = document.createElement('link')
                if (!/^https?\:\/\//.test(hrefs[i])) {
                    style.type = 'text/css'
                }
                style.href = hrefs[i]
                style.rel = 'stylesheet'

                if (scope._rawStyles === undefined) {
                    scope._rawStyles = []
                }
                scope._rawStyles.push([hrefs[i], style])
                scope._styles.push(document.head.appendChild(style))

                scope.$on('$destroy', this.clean_styles)
            }
        },

        clean_styles: function () {
            var removables = []
            for (var key in scope._rawStyles) {
                console.log('deleting style ' + scope._rawStyles[key][0])
                scope._styles[key].parentNode.removeChild(scope._rawStyles[key][1])
                removables.push(key)
            }

            scope._styles = scope._styles.filter(function (v) { return (removables.indexOf(v) !== -1)? true: false })
            scope._rawStyles = scope._rawStyles.filter(function (v) { return (removables.indexOf(v) !== -1)? true: false })
        },

        script: function (inp) {
            var hrefs = []
            if (typeof inp === 'string') {
                hrefs.push(inp)
            } else {
                hrefs = inp
            }

            scope._scripts = []
            for (var i in hrefs) {
                console.log('loading javascript: ' + hrefs[i])
                var script = document.createElement('script')
                if (!/^https?\:\/\//.test(hrefs[i])) {
                    script.type = 'text/javascript'
                }
                script.src = hrefs[i]

                if (scope._rawScripts === undefined) {
                    scope._rawScripts = []
                }
                scope._rawScripts.push([hrefs[i], script])
                scope._scripts.push(document.head.appendChild(script))

                scope.$on('$destroy', this.clean_scripts)
            }
        },

        clean_scripts: function () {
            var removables = []
            for (var key in scope._rawScripts) {
                console.log('deleting script ' + scope._rawScripts[key][0])
                scope._scripts[key].parentNode.removeChild(scope._rawScripts[key][1])
                removables.push(key)
            }

            scope._scripts = scope._scripts.filter(function (v) { return (removables.indexOf(v) !== -1)? true: false })
            scope._rawScripts = scope._rawScripts.filter(function (v) { return (removables.indexOf(v) !== -1)? true: false })
        }

    }
}])

Can be used in routes like this:

(function(){
    angular.module('app')
        .config(['$routeProvider',
            function config($routeProvider) {
                $routeProvider.
                    when('/dashboard', {
                        templateUrl: 'hipermídia/dashboard.template.html',
                        controller: 'dashboard_controller',
                        resolve: {
                            factory: function (Res) {
                                controllersAndServices(Res, {styles: 'estilos/dashboard.css' ,
                                    scripts: 'scripts/load-image.all.min.js'})
                            }
                        }
                    }).

                otherwise('/')
            }
        ])

    const controllersAndServices = function (Res, Routes) {
        Res.clean_scripts()
        Res.clean_styles()

        if ('scripts' in Routes) {
            Res.script(Routes.scripts)
        }
        if ('styles' in Routes) {
            Res.style(Routes.styles)
        }
    }

})()

The values in the conf object you pass can be arrays or strings, and can point to any valid url (CDN, direct URL, or local)

While unloading is mostly cosmetic (aids in visually discerning which libraries are active), this does the job.