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Selenium.common.exceptions.StaleElementReferenceException during page refresh

The page contains some data (a table with several rows). There is a Refresh button that reloads and redraws some elements on the page without reloading static data (ajax).

I am trying to create the right test for this page, but sometimes I get a StaleElementReferenceException.

My code (python):

from selenium import webdriver
browser=webdriver.Firefox()
browser.get('http://mytisite')
browser.implicitly_wait(10)
browser.find_element_by_id('start').click()
while browser.find_element_by_id('status').text!='Done':
    browser.find_element_by_id('refresh').click()
    for row in browser.find_elements_by_class_name('datarow'):
        if not is_correct(row.text):
           print "incorrect"
    time.sleep(10)

1 out of 5 iterations fails on the line "if not is_correct (row.text)":

selenium.common.exceptions.StaleElementReferenceException: 
 Message: u'Element not found in the cache - perhaps the page 
 has changed since it was looked up' ; Stacktrace: Method 
 fxdriver.cache.getElementAt threw an error in 
 resource://fxdriver/modules/web_element_cache.js

The main problem: the page already contains the previous data, so I get a race between updating ajax and requesting the webdriver element find_elements_by_class_name('datarow').

How can I correctly resolve the race between ajax update and webdriver? Thank.

+5
2

, python. WebDriver Java, () python. , AJAX Selenium.

1. -. - DOM .

driver.manage().timeouts().implicitlyWait(60, TimeUnit.SECONDS);

2. . ! . , WebDriver . WebDriverWait .

WebDriverWait wait = new WebDriverWait(driver, 60/*timeout in seconds*/);
WebElement element = wait.until(ExpectedConditions.elementToBeClickable(By.id("refresh")));

ExpectedConditions , .

Java, . . , . , WebDriverWait.

WebDriverWait wait = new WebDriverWait(driver, 60/*timeout in seconds*/);
ExpectedCondition<Boolean> untilIFindStatus = ExpectedConditions
                    .elementToBeSelected(By.id("status"));
while (wait.until(untilIFindStatus)) {
        WebElement refresh = wait.until(ExpectedConditions
                        .elementToBeClickable(By.id("refresh")));
        refresh.click();
        List<WebElement> allRows = wait.until(ExpectedConditions
                .presenceOfAllElementsLocatedBy(By.className("datarow")));
             for (WebElement row : allRows) {
                if (row.getText().equals("awesome"))
                    System.out.println("do something");
             }
 }

, AJAX jQuery. jQuery.active , , . javascript document.readyState. , 'click' AJAX.

ExpectedCondition<Boolean> jQueryActive_toBeZero = new ExpectedCondition<Boolean>()   {
        public Boolean apply(WebDriver driver) {
           try {
            return ((Long) jsExecutor
                .executeScript("return jQuery.active") == 0) ? true
                            : false;
         } catch (WebDriverException e) {
             log.debug("It looks like jQuery is not available on the page, skipping the jQuery wait, check stack trace for details");
             return true; //skip the wait
         }
           }
       };
ExpectedCondition<Boolean> document_readyState_toBeComplete = new ExpectedCondition<Boolean>() {
        public Boolean apply(WebDriver driver) {
          return jsExecutor.executeScript("return document.readyState")
             .toString().equals("complete") ? true : false;
         }
     };
    wait.until(jQueryActive_toBeZero);
    wait.until(document_readyState_toBeComplete);
+4

, , :

  • .
  • DOM

+3

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