Sunday, May 25, 2014

autocomplete

Let us implement the autocomplete functional test for Google search page, when you type, o,r,a,c,l,e, it popup some matching words or phrases in the flyout area and you can select the one you are looking for.

There are 5 actions in autocomplete,
  • Find the input box
  • Send keys one by one
  • Try to find the suggestion you are looking for in the suggestion area
  • Click the suggested item
  • Explicitly wait for it

  • The input field for us to enter criteria is named "q", so you can use By.name("q") to find it and type the characters of Oracle one by one into it and wait for "Oracle" appears in the selection area and click it.



    It is difficult to locate the suggestion items since there is no obvious selection criteria to find them.



    You can use Firebug to find its absolute xpath, to get some idea but it can be used in the tests since the structure of the page may change and it will not work,

    /html/body/table/tbody/tr/td[2]/table/tbody/tr/td/div/table/tbody/tr/td/span
    


    If you are not familiar with xpath, you can use complex search to find a container first and from the container, find the element. This autocomplete suggestion is inside a table with class "gssb_c", so we can findElement of the table first, and the findElements of all the span elements inside that table and find the one with the text "oracle" you try to type in,

    // ☹ this is a bad example, please don't follow the style.
    try {
       WebElement table = webDriver.findElement(By.className("gssb_c"));
       List<WebElement> spans = table.findElements(By.tagName("span"));
       WebElement oracle = find(spans, 
               new Predicate<WebElement>() {
                  @Override
                  public boolean apply(WebElement span) {
                     return span.getText().equals("oracle");
                  }
               });
       oracle.click();
    } catch (NoSuchElementException e) {
       e.printStackTrace();
    }
    


    This is not the complete logic, it is just the part to find the "oracle" from the suggestion list, it is already very verbose.

    Selenium capsules, a new Selenium framework, uses a locator pattern to abstract the element locating logic to make the test code cleaner, in the autoCompleteUsingLocator test from following code block.

    Note, () -> className("gssb_c") is a lambda expression introduced in Java 8.

     //   ☺ This is a good example.
     new ElementTryLocator<AbstractPage>(() -> className("gssb_c"))
         .and(new ElementsLocator<>(SPAN))
         .and(new FirstMatch<>(TEXT.and(new IsStringEqual("oracle")))));
    


    It is a little bit cleaner, but still very complex.





    After rewriting the search using By xpath, it only has one findElement method call, which is much better than the navigational locating strategy, so you can greatly simplify the test if you know how to use xpath.

    // ☹ this is a bad example, please don't follow the style.
    try {
       WebElement oracle = webDriver.findElement(
           By.xpath("//table[contains(concat(' ', @class, ' '), 'gssb_c')]/descendant::span[text()='oracle']");
       oracle.click();
    } catch (NoSuchElementException e) {
       e.printStackTrace();
    }
    


    But it is still not clean if the By.xpath call appears multiple times in different tests,

       By.xpath("//table[contains(concat(' ', @class, ' '), 'gssb_c')]/descendant::span[text()='oracle']");
    


    By using Selenium Capsules framework, you can actually put this xpath string literal inside an enum and use the enum in the tests,

    //   ☺ This is a good example.
    import org.openqa.selenium.By;
    
    import java.util.function.Supplier;
    
    import static org.openqa.selenium.By.xpath;
    
    public enum Xpath implements Supplier<By> {
    
        DIV_CONTAINER_ID("//div[@id='container']"),
        ORACLE_AUTOCOMPLETE("//table[contains(concat(' ', @class, ' '), 'gssb_c')]/descendant::span[text()='oracle']"),
        QUANTITY("//div[@id='ys_cartInfo']/descendant::input[@name='cartDS.shoppingcart_ROW0_m_orderItemVector_ROW0_m_quantity']");
    
        private final By by;
    
        private Xpath(String id) {
            this.by = xpath(id);
        }
    
        @Override
        public By get() {
            return by;
        }
    
        @Override
        public String toString() {
            return by.toString();
        }
    }
    
    


    Now the test can be rewritten as simple as one line of code,

        //   ☺ This is a good example.
        @Test
        public void autoCompleteUsingXpath() {
            googlePage.autocomplete(Q, "oracle", new ElementTryLocator<>(ORACLE_AUTOCOMPLETE));
        }
    


    Even you don't want to use a framework, putting locating strategy in enum can still simplify code, unlike the above code, you can just use ORACLE_AUTOCOMPLETE as a parameter, you need to call get() method to get a By object, but it is still cleaner than using xpath string literals directly in the code,

    
    //   ☺ This is an OK example.
    
    try {
       WebElement oracle = webDriver.findElement(ORACLE_AUTOCOMPLETE.get());
       oracle.click();
    } catch (NoSuchElementException e) {
       e.printStackTrace();
    }
    

    versus original,
    // ☹ this is a bad example, please don't follow the style.
    try {
       WebElement oracle = webDriver.findElement(
           By.xpath("//table[contains(concat(' ', @class, ' '), 'gssb_c')]/descendant::span[text()='oracle']");
       oracle.click();
    } catch (NoSuchElementException e) {
       e.printStackTrace();
    }
    

    Now let us have a comparison between the tests written with and without using framework,

    1. autoCompeleteUsingSelenium doesn't use framework, it uses Selenium directly.
    2. autoCompleteUsingXpath uses framework,



    Cohesively, all By selectors can be organized into one package, selectors to encourage people reuse existing definitions, the name of that package should be bysuppliers, I found out selectors is a more meaningful name since that's the purpose of those classes.

    By Selector Suppliers and all its member classes are enum types implementing Supplier interface to provide a by selector for Selenium WebDriver or WebElement, this is explained in this blog entry, functional selenium

    Saturday, May 24, 2014

    functional selenium

    Java 8 incorporated part of Google Guava library and provides nice support for functional programming, I found it extremely helpful when working with Selenium.

    These is a new class in Java 8 called Supplier, it only has one method get() which will return the type you specified.

    Then I used enum or organize the same By type into enum which implements Supplier,

    0. By xpath

    1. By cssSelector



    2. By tagName



    I should complete this TagName class with all HTML tags.

    3. By name



    4. By Others



    and a Locator to locate one or a list of elements,



    and a helper method to use ElementsLocator to find a Stream of Element meeting the criteria. ElementsLocator extends AbstractLocator which implements Function interface from Java 8.

    Function is too generic so I extend it into another interface called Locator which is more suitable concept for Selenium tests, locating something from somewhere,



    and use it in another page object to locate the Button,



    This code snippet is to combine 3 functions into one,



    Use the Supplier enum constants to locate elements on the form or page and either enter text or click it,

    With static imports,



    or with full class qualifier,





    put(QUANTITY, 2) is to type the text "2" into an input field QUANTITY which is an enum constant in Name class to specify

    By.name("cartDS.shoppingcart_ROW0_m_orderItemVector_ROW0_m_quantity") 
    


    or another enum constant in Xpath class,
    By.xpath("//div[@id='ys_cartInfo']/descendant::input[@name='cartDS.shoppingcart_ROW0_m_orderItemVector_ROW0_m_quantity']");
    


    It doesn't care which selector you are using, as long as it implements Supplier interface so the framework can get a By selector from the parameter, if it is from Name, it is a ByName selector, if it is from Xpath, it is a ByXpath selector.

    and button(UPDATE) is to locate the UPDATE button, UPDATE is an enum constant in CssSelector to specify

    By.cssSelector("input[value='Update']");
    


    The advantage of having this Supplier enums is to reduce the number of methods of the helper API, before I came out this Supplier solution, I have used the following approach,
    findElementById,
    findElementByName,
    ...
    findElementByXpath,
    findElementsById,
    findElementsByName,
    ...
    findElementsByXpath

    While now I only have three methods,



    Element findElement(By by);

    This is same as the original Selenium SearchContext.findElement

    Element untilFindElement(By by);

    This is a new method after calling the original Selenium SearchContext.findElement it waits until an element is found or timeout

    Stream findElements(By by); This is similar to original SearchContext.findElements, just it uses Stream rather than list, Stream is a new interface from Java 8. One implementation is in Browser interface as a default method, Element::new is called method refernece in Java 8, the following two code snippets have the same functionality while the latter one is using Lambda Expression

        default public Stream<Element> findElements(Supplier<By> by) {
            return findElements(by.get()).stream().map(Element::new);
        }
    
        default public Stream<Element> findElements(Supplier<By> by) {
            return findElements(by.get()).stream().map(element -> new Element(element));
        }
    
    


    By using Supplier, you can hide Selenium By inside an enum and make the test codes very clean,

    separate test data from page

    1. Input Data

    Test data can be organized into Java Value Object or POJO as people call it, then used as the parameter for the methods of Page Object. For example, in a shopping page, it can have methods such setBillingAddress, setCreditCard and setOtherInformation which take a parameter object such as Address, CreditCard and OtherInfomation, etc.



    Here is the Address Java Value Object, it is a POJO, since all its properties are final, all its fields can be public without getter to save some extra code.


    The address can be a bean in a spring config file, or a row in jBehave table, depends on your preference,



    Then the test can be as simple as this,



    This example just showed you how to separate test data from page and use the data to populate the form with input, radio button, select and checkbox widgets. However, It is not the ultimate way to manage test data. There are other frameworks, i.e. jBehave which can be used to organize the tests in tabular format. Please check out their websites for more information.


    2. Output Data

    Expectation data can also be organized into Java objects, for example, ErrorMessages,





    So in the test, you can just call,
            assertEquals(expectedErrorMessages, cartPage.getErrorMessages());
    

    And in the case of test failure, it will display meaningful error messages,

    On page,



    On IDE,



    Please implement toString method of this expectation class, without it, the reported error would be like following, which really doesn't tell us much.

    add support for new browsers

    There is an enum based Browser support in Selenium Capsules, the code is here, Browser


    The Firefox is,

    It doesn't contain all of the browsers on the market, how to extend it to support new browsers?
    It is easy, just add another class to implement Browser interface then you can use this new Browser type to support page framework,

    The difference between Firefox and FirefoxOnWindows is FirefoxOnWindows also implements Browser interface while Firefox doesn't.

    So Firefox itself can't be used as a parameter the constructor of the AbstractPage, what's the reason for this? this reason is simple, since it is used to be part of the enum constants Browsers, so Browsers is preferred class to use in the codebase, then it can used as value in Spring context file and use Java property to choose the browser for the tests.

    browser=FIREFOX
    
    or
    browser=CHROME
    

    Sunday, May 18, 2014

    jquery calendar in java 8

    package com.algocrafts.calendar;
    
    import com.algocrafts.conditions.IsEquals;
    import com.algocrafts.converters.Filter;
    import com.algocrafts.converters.FirstItem;
    import com.algocrafts.decorators.AbstractPage;
    import com.algocrafts.decorators.Element;
    import com.algocrafts.locators.ElementLocator;
    import com.algocrafts.locators.ElementTryLocator;
    import com.algocrafts.locators.ElementsLocator;
    import com.algocrafts.locators.Locator;
    
    import static com.algocrafts.conditions.ElementFunction.CLICK_IF_NOT_NULL;
    import static com.algocrafts.conditions.PageCondition.CALENDAR_NOT_DISPLAYED;
    import static com.algocrafts.converters.GetText.TEXT;
    import static com.algocrafts.converters.Ordinal.ORDINAL;
    import static com.algocrafts.converters.StringToInt.PARSE_INT;
    import static com.algocrafts.converters.ToMonth.TO_MONTH;
    import static com.algocrafts.searchmethods.ByClassName.*;
    import static com.algocrafts.searchmethods.ById.UI_DATEPICKER_DIV;
    import static com.algocrafts.searchmethods.ByTagName.TD;
    
    /**
     * This is the reference implementation of the Calendar interface which can be
     * operated by a DatePicker.
     * The location of the date picker is here,
     * http://jqueryui.com/datepicker/
     *
     * @author Yujun Liang
     * @since 0.1
     */
    public class JQueryCalendar implements Calendar {
    
        private final AbstractPage page;
        private final Locator<AbstractPage, Element> trigger;
    
        /**
         * Constructor of the JQueryCalendar, an active page and a search
         * criteria of the trigger element.
         *
         * @param page
         * @param trigger
         */
        public JQueryCalendar(AbstractPage page, Locator<AbstractPage, Element> trigger) {
            this.page = page;
            this.trigger = trigger;
        }
    
        @Override
        public void show() {
            trigger.and(CLICK_IF_NOT_NULL).apply(page);
        }
    
        @Override
        public int currentYear() {
            return new ElementLocator<AbstractPage>(UI_DATEPICKER_DIV)
                .and(new ElementLocator<>(UI_DATEPICKER_HEADER))
                .and(new ElementLocator<>(UI_DATEPICKER_YEAR))
                .and(TEXT)
                .and(PARSE_INT)
                .apply(page);
        }
    
        @Override
        public int currentMonth() {
            return new ElementLocator<AbstractPage>(UI_DATEPICKER_DIV)
                .and(new ElementLocator<>(UI_DATEPICKER_MONTH))
                .and(TEXT)
                .and(TO_MONTH)
                .and(ORDINAL)
                .apply(page);
        }
    
        @Override
        public void previousMonth() {
            new ElementLocator<AbstractPage>(UI_DATEPICKER_DIV)
                .and(new ElementLocator<>(UI_DATEPICKER_PREV))
                .and(CLICK_IF_NOT_NULL)
                .apply(page);
        }
    
        @Override
        public void nextMonth() {
            new ElementLocator<AbstractPage>(UI_DATEPICKER_DIV)
                .and(new ElementLocator<>(UI_DATEPICKER_NEXT))
                .and(CLICK_IF_NOT_NULL)
                .apply(page);
        }
    
        @Override
        public void pickDay(int day) {
            new ElementLocator<AbstractPage>(UI_DATEPICKER_DIV)
                .and(new ElementLocator<>(UI_DATEPICKER_CALENDAR))
                .and(new ElementsLocator<>(TD))
                .and(new Filter<>(new IsEquals(TEXT, day)))
                .and(new FirstItem<>())
                .and(CLICK_IF_NOT_NULL)
                .apply(page);
            new ElementLocator<AbstractPage>(UI_DATEPICKER_DIV)
                .and(new ElementTryLocator<>(UI_DATEPICKER_CLOSE))
                .and(CLICK_IF_NOT_NULL)
                .apply(page);
            page.until(CALENDAR_NOT_DISPLAYED);
        }
    
    }
    

    Friday, May 9, 2014

    a browser factory using enum (200 mcg)

    When testing web applications, we often need to switch the browsers. There are many ways to manage this, usually people use if else statement.

    There is nothing wrong with if else statement, but if you have many branches of else if statement, the code is extremely fragile. Many patterns have been introduced to avoid using if statement, among them, Factory, Factory Method, Strategy are most popular ones. By the assistance from Spring, we can actually use enum to achieve this, here is the enum of browsers we are going to support in the tests, we can always add more if we want to support more browsers.


    Firefox is one of the Browsers
    Then declare this Browser as an instance variable of AbstractPage and passed in from Constructor,
    In a Spring managed property file, i.e. pages.properties, add the name of the enum,
    browser=FIREFOX
    


    The way to let Spring know about the property file is to add this bean into Spring context xml file.
        
            
                
                    classpath:properties/pages.properties
                
            
        
    

    In your code, whenever you want to access webDriver instance, just simply call,
    This also solves the incompatibility issue caused by Firefox upgrade, mentioned here. And you can run test for different browsers,



    And since this Browser interface extends WebDriver, it can be used as the constructor parameter to Actions class and perform advanced actions such mouseOver, drapAndDrop, etc.

         Actions action =  new Actions(CHROME);
    



    Let us compare the tests with or without this browser factory,

        //This is an ugly test not using page framework, it has the same function as the test below. :(
        @Test
        public void dragAndDropChrome() throws InterruptedException {
            System.setProperty("webdriver.chrome.driver", "src/main/resources/chrome/chromedriver");
            WebDriver webDriver = new ChromeDriver();
            webDriver.get("http://www.w3schools.com/html/html5_draganddrop.asp");
            WebElement source = webDriver.findElement(id("drag1"));
            System.out.println(source.getAttribute("src"));
            WebElement target = webDriver.findElement(id("div2"));
            System.out.println(target.getTagName() + "=" + target.toString());
    
            Actions builder = new Actions(webDriver);
    
            Action dragAndDrop = builder.clickAndHold(source)
                    .moveToElement(target)
                    .release(source)
                    .build();
            dragAndDrop.perform();
        }
    

        @Test
        public void testDragAndDrop() {
            Browser browser = Browsers.FIREFOX;
            browser.get("http://www.w3schools.com/html/html5_draganddrop.asp");
            browser.dragAndDrop(id("drag1"), id("div2"));
        }