如何在每次py.test断言失败时调用方法？

Question

背景：

我正在使用py.test和pytest-selenium，现在我想在断言失败时截取页面截图。

目前，我已经在我的基本页面对象类中定义了小帮助器方法：

class PageBase(object):
    def __init__(self,driver):
        self.driver = driver
        self.fake = Factory.create()

    def screenshot(self,name):
        self.driver.save_screenshot(datetime.now().strftime('%Y-%m-%d %H:%M:%S') + 'scr_'+name+'.png')

    @contextmanager
    def wait_for_page_load(self, timeout=45):
        old_page = self.driver.find_element_by_tag_name('html')
        yield
        WebDriverWait(self.driver, timeout).until(
            EC.staleness_of(old_page)
        )

问题是，我想让它成为自动机制而不是“手动”用法：(测试类示例)：

class TestLogin:
    @allure.feature('Ability to login into admin panel')
    def test_admin_login(self, prepare, page):

        print URLMap.admin('test')
        driver = prepare
        driver.get(URLMap.admin(page))

        login_page = LoginPage(driver)
        assert login_page.is_page_correct(),'Login page not loaded correctly'

        login_page.fill_login_data('testadmin','testadmin')
        login_page.click_login_button()
        assert login_page.is_user_logged_in(),'User cannot log in with provided credentials'
        login_page.screenshot(page+'_logged_in')

如何针对每个断言失败运行特定的方法？

Answer 1

我个人没有使用过，但这可能是您的解决方案：https://pytest.org/latest/example/simple.html#writing-well-integrated-assertion-helpers

这也可能会有帮助：https://pytest.org/latest/assert.html#advanced-assertion-introspection

Answer 2

你必须使用钩子。https://docs.pytest.org/en/latest/example/simple.html#post-process-test-reports-failures

@pytest.hookimpl(hookwrapper=True, tryfirst=True)
def pytest_runtest_makereport(item, call):
    outcome = yield
    rep = outcome.get_result()
    setattr(item, "rep_" + rep.when, rep)
    return rep

@pytest.fixture(autouse=True, scope='session')
def driver(platform, request):
    """ some driver setup code """
    yield driver

    if request.node.rep_call.failed:
        try:
            driver.get_screenshot_as_png()
        except:
            pass

    driver.quit()

如果您想附加一个屏幕截图来吸引报告，只需执行以下操作：

@pytest.fixture(autouse=True, scope='session')
def driver(platform, request):
    """ some driver setup code """
    yield driver

    if request.node.rep_call.failed:
        # Make the screen-shot if test failed:
        try:
            allure.attach(
                driver.get_screenshot_as_png(),
                name=request.function.__name__,
                attachment_type=allure.attachment_type.PNG)
        except: 
            """ do something """

        driver.quit()

Answer 3

我认为screenShotInSelenium页面应该为您提供足够的信息，告诉您在满足断言条件时如何创建屏幕截图。

您缺少的是@AfterMethod的使用