{"id":16548,"date":"2016-05-04T08:00:27","date_gmt":"2016-05-04T12:00:27","guid":{"rendered":"https:\/\/simpleprogrammer.com\/?p=16548"},"modified":"2018-01-12T17:31:58","modified_gmt":"2018-01-12T22:31:58","slug":"selenium-webdriver-tutorial-master-synchronization","status":"publish","type":"post","link":"https:\/\/simpleprogrammer.com\/selenium-webdriver-tutorial-master-synchronization\/","title":{"rendered":"Selenium Tutorial"},"content":{"rendered":"

Why is it important to have proper synchronization for your automated tests?<\/strong>\\n\\nHave you ever dealt with flaky automated checks? Checks that fail intermittently and you are unsure why? How about checks that fail in your Continuous Integration environment, but work locally?\\n\\nAll of these could be a result of improper synchronization within your tests. Synchronization refers to the idea that the speed of your automated check should coincide with the speed of the application under test (AUT). Basically, if the code of your automated check runs faster or slower than the actual AUT, you will experience all of the problems that I listed above.\\n\\nIf your code runs too fast, it will not find HTML elements on a page that you were expecting to be there. If your code runs too slow, you will be wasting valuable time during test execution. Either way, this destroys the reputation of your functional checks and deems them as \u201cflaky\u201d or \u201cslow\u201d. No automated check of yours should wear those scarlet letters.\\n\\nTherefore, proper synchronization techniques with automated functional GUI tests are extremely important for any Test Automation Engineer to know. This tutorial will take a very deep look at all of the timeouts and synchronization options available to you with Selenium Webdriver.\\n\\n<\/p>\n

Pre-requisites<\/h2>\n

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\\n\\nI am making the assumption that you have or know the following:\\n\\n<\/p>\n

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  1. \\nSome flavor of Visual Studio installed\\n\\n-Although I will teach using C#, most of the concepts and ideas here can be applied to other bindings like Java, Ruby, and so on.\\n<\/li>\n

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  2. General knowledge of C#<\/li>\n

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  3. Basic understanding of Selenium Webdriver<\/a><\/li>\n

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  4. Understanding of element locators using HTML<\/li>\n

    \\n<\/ol>\n

    \\n\\n<\/p>\n

    What Application Will we Test?<\/h2>\n

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    \\n\\nThis is the AUT<\/a> that we will be working with today. A Selenium guru by the name of Dave Haeffner uses this application to teach Selenium Webdriver. The goal of the test is really simple:\\n\\n<\/p>\n

      \\n <\/p>\n
    1. Navigate to the page<\/li>\n

      \\n <\/p>\n

    2. Click button with id = \u201cstart\u201d<\/li>\n

      \\n <\/p>\n

    3. Make sure that element with id = \u201cfinish\u201d is present on the page<\/li>\n

      \\n<\/ol>\n

      \\n\\n<\/p>\n

      Improper Synchronization Example<\/h2>\n

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      \\n\\nI wrote a quick test<\/a> to give you an example of what can happen when your synchronization strategy isn\u2019t up to par. Take a look at this code:\\nIf you try to run the test in your Visual Studio, you will probably receive a similar message like in the image below.\\n\\n\"selenium\"\\n\\nSo why did this test fail? Take a moment to think about it and walk through the application or step through the code<\/a>.\\n\\nThe automated check failed because of improper synchronization. After pressing the \u201cstart button\u201d, there is a loading screen that we must wait for 5 seconds. However, in our automated check, we don\u2019t have such a synchronization point. Therefore, when our test executes the line of code below, the Webdriver API comes back within 500ms and says that this element is not visible. Of course, it\u2019s not visible, there is a stupid loading icon that we didn\u2019t account for:\\n\\nTo resolve synchronization problems, I will teach you 3 types of techniques to apply to your tests.\\n\\n<\/p>\n

      What is an IMPLICIT<\/strong> Wait in Selenium Webdriver?<\/h2>\n

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      \\n\\nAn implicit wait<\/strong> in Selenium came from Watir\u2019s implicit wait idea. Here we are telling the Webdriver to poll the DOM for a specific amount of time when trying to find an element or elements. The default setting is 0 seconds. Once set, the timeout is set for the life of the driver, until it is changed again.\\n\\n(Selenium HQ<\/a>)\\n\\n<\/p>\n

      How do you use an Implicit Wait?<\/h5>\n

      \\n\\nOnce you create a type of driver, you will have access to the ImplicitlyWait() method. This method takes a TimeSpan object which you can use to specify the maximum of time that you want the driver to wait before throwing a NoSuchElementException<\/strong>.\\n\\n<\/p>\n

      What are the Advantages and Disadvantages of Implicit Waits?<\/h5>\n

      \\n\\nAdvantages<\/strong>\\n\\n<\/p>\n