Flexible tests with DataProviders and Strategies

DataProviders

TestNG DataProviders are a powerful way to parameterize test classes, allowing you to run a single test method many times with different inputs.

For example, say we'd like to assert that a group of web search engines have a 'search box' on their home page, but because they're maintained by different companies, don't have a common HTML locator. Here we use a DataProvider to maintain a list of URLs and their corresponding 'search box' IDs, go to the URL and assert the search box is visible.

	@DataProvider(name = "searchBoxProvider")
	public Object[][] searchBoxProvider() {
	return new Object[][] {
	{ "http://www.google.com", "lst-ib" },
	{ "https://duckduckgo.com", "search_form_input_homepage"},
	{ "https://www.dogpile.com/", "topSearchTextBox"},
	{ "http://www.bing.com", "sb_form_q"}
	};
	}
	@Test(dataProvider = "searchBoxProvider")
	public void shouldHaveVisibleSearchBox(String url, String searchBoxId) {
	WebDriver driver = new FirefoxDriver();
	driver.get(url);
	WebElement searchBox = driver.findElement(By.id(searchBoxId));
	assertTrue(searchBox.isDisplayed());
	}

view raw SearchBoxTest.java hosted with ❤ by GitHub

However, let's say that one day DuckDuckGo adds an ad to their main page that hides the 'search box' until you close it, but we still want to assert that the 'search box' is still there. We could add some complexity to our @Test method that clicks the ad, but only for duckduckgo.com, or we could add a second DataProvider and a second @Test that does the additional step. Both of these make the test awful to read, unfortunately.

	@DataProvider(name = "searchBoxProvider")
	public Object[][] searchBoxProvider() {
	return new Object[][] {
	{ "http://www.google.com", "lst-ib" },
	{ "https://duckduckgo.com", "search_form_input_homepage"},
	{ "https://www.dogpile.com/", "topSearchTextBox"},
	{ "http://www.bing.com", "sb_form_q"}
	};
	}
	@Test(dataProvider = "searchBoxProvider")
	public void shouldHaveVisibleSearchBox(String url, String searchBoxId) {
	WebDriver driver = new FirefoxDriver();
	driver.get(url);
	if (StringUtils.equals(url, "https://duckduckgo.com")) {
	WebElement adCloseButton = driver.findElement(By.id('mainAdCloseButton'));
	adCloseButton.click();
	}
	WebElement searchBox = driver.findElement(By.id(searchBoxId));
	assertTrue(searchBox.isDisplayed());
	}

view raw SearchBoxTestWithAds.java hosted with ❤ by GitHub

Using Strategies

I've found that using DataProviders to provide assertion Strategies is a great way to solve this type of problem. Here we create interface SearchEngine, and implementing classes DefaultSearchEngine and DuckDuckGo to abstract the varying behavior away of preparing the page from the test method.

	interface SearchEngine {
	static void preparePage(WebDriver driver);
	}
	class DefaultSearchEngine implements SearchEngine {
	static void preparePage(WebDriver driver) {
	// do nothing
	}
	}
	class DuckDuckGo implements SearchEngine {
	static void preparePage(WebDriver driver) {
	WebElement adCloseButton = driver.findElement(By.id('mainAdCloseButton'));
	adCloseButton.click();
	}
	}

view raw SearchEngine.java hosted with ❤ by GitHub

And then provide a SearchEngine to the test method using searchBoxProvider.

	@DataProvider(name = "searchBoxProvider")
	public Object[][] searchBoxProvider() {
	return new Object[][] {
	{ "http://www.google.com", "lst-ib" , new DefaultSearchEngine()},
	{ "https://duckduckgo.com", "search_form_input_homepage", new DuckDuckGo()},
	{ "https://www.dogpile.com/", "topSearchTextBox", new DefaultSearchEngine()},
	{ "http://www.bing.com", "sb_form_q", new DefaultSearchEngine()}
	};
	}
	@Test(dataProvider = "searchBoxProvider")
	public void shouldHaveVisibleSearchBox(String url, String searchBoxId, SearchEngine searchEngine) {
	WebDriver driver = new FirefoxDriver();
	driver.get(url);
	searchEngine.preparePage(driver);
	WebElement searchBox = driver.findElement(By.id(searchBoxId));
	assertTrue(searchBox.isDisplayed());
	}

view raw SearchBoxTestWithAds.java hosted with ❤ by GitHub

Proxy Nodejitsu drone witth nginx

When developing an Angluar application, I needed to make requests to remove servers, and encountered the "Access-Control-Allow-Origin" problem. To overcome this, I decided to proxy the remote server using nginx. Since a remote server was a nodejitsu drone, I needed to modify my nginx configuration a little further than normal:

	upstream api {
	# server 127.0.0.1:3030; # Standard proxy_pass server to locally running server
	server librecms-api.jit.su:80; # proxy_pass server to remote nodejitsu drone.
	}
	server {
	listen 80;
	server_name localhost;
	root /var/www/librecms/src/angular/app;
	underscores_in_headers on;
	location /api/ {
	##### proxy_pass configuration for all upstream servers
	proxy_set_header X-Real-IP $remote_addr;
	proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
	proxy_set_header X-NginX-Proxy true;
	proxy_pass http://api/;
	proxy_redirect off;
	proxy_http_version 1.1;
	proxy_set_header Upgrade $http_upgrade;
	proxy_set_header Connection "upgrade";
	#### NOTE THIS IS SPECIFIC FOR NOTEJITSU DRONES.
	#### Must set Host header to domain of nodejitsu drone.
	proxy_set_header Host librecms-api.jit.su;
	}
	location / {
	# Application specific
	index index.html;
	try_files $uri $uri/ /index.html =404;
	}
	}

view raw gistfile1.txt hosted with ❤ by GitHub

Note the proxy_set_header Host line. This is needed because nodejitsu proxies their drones according to the Host header (docs).

Unit testing state transitions with ui-router and karma/jasmine

Testing ui-router state transitions with karma/jasmine is straightforward. The unit test:

	'use strict';
	describe('Controller: CourseCtrl', function () {
	// load the controller's module
	beforeEach(module('myApp'));
	// load controller widgets/views/partials
	var views = [
	'views/course.html',
	'views/main.html'
	];
	views.forEach(function(view) {
	beforeEach(module(view));
	});
	var CourseCtrl,
	scope;
	// Initialize the controller and a mock scope
	beforeEach(inject(function ($controller, $rootScope) {
	scope = $rootScope.$new();
	CourseCtrl = $controller('CourseCtrl', {
	$scope: scope
	});
	}));
	it('should should transition to main.course', inject(function ($state, $rootScope) {
	$state.transitionTo('main.course');
	$rootScope.$apply();
	expect($state.current.name).toBe('main.course');
	}));
	});

view raw gistfile1.js hosted with ❤ by GitHub

And karma configuration:

	module.exports = function(config) {
	'use strict';
	config.set({
	basePath: '',
	frameworks: ['jasmine'],
	files: [
	'app/bower_components/angular/angular.js',
	'app/bower_components/angular-mocks/angular-mocks.js',
	'app/scripts/*.js',
	'app/scripts/**/*.js',
	'app/views/**/*.html',
	'test/spec/**/*.js'
	],
	exclude: [],
	port: 8080,
	preprocessors: {
	'app/views/**/*.html': 'html2js'
	},
	ngHtml2JsPreprocessor: {
	stripPrefix: 'app/'
	},
	logLevel: config.LOG_INFO,
	autoWatch: false,
	// - IE (only Windows)
	browsers: ['PhantomJS'],
	singleRun: false
	});
	};

view raw gistfile1.txt hosted with ❤ by GitHub

Note the html preprocessor and inclusion of the views in the "files" array.