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Debugging random webdriver issues on jenkins

So one of my friend was facing one issue where he wrote a bunch of webdriver tests and they all work fine but when he runs on jenkins slave it randomly fails.  He runs his jenkins job hourly and problem is that it fails may be 4 times in 24 hours.  So how do you debug the issue, well he was adding loggers in the test to figure this out and then plodding over logs to figure out what went wrong. This is quite a bit of guess work and I thought sometimes a picture is better than 1000 words. So it would be nice if I could take a screenshot when the test errors out and then save it as an artifact. Guess what the webdriver already has an api for that. So all i needed to do was to add a TestRule like this and add the screenshots directory in the publish artifacts in jenkins.  I will know it in a week or so if this would save him a lot of time or not.

    @Rule
    public TestRule testWatcher = new TestWatcher() {
        @Override
        public void failed(Throwable t, Description test) {
            takeScreenshot(test.getDisplayName() + UUID.randomUUID().toString());
        }

        private void takeScreenshot(String screenshotName) {
            WebDriver webDriver = driver.getWebDriver();
            if (webDriver instanceof TakesScreenshot) {
                File targetDir = new File("seleniumScreenshots");
                File targetFile = new File(targetDir, screenshotName + ".png");
                logger.info("Taking Screenshot path = " + targetFile);
                File tempFile = ((TakesScreenshot) webDriver).getScreenshotAs(OutputType.FILE);
                try {
                    FileUtils.copyFile(tempFile, targetFile);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    };

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