关于 PageFactory 的概念主要是Java中内置了PageFactory类。
import org.openqa.selenium.support.PageFactory; ……
例子，http://libin0019.iteye.com/blog/1260090
Python（Selenium）中没有这个类。 PageFactory 的概念和Page Object应该类似，属于一种设计模式。所以并不局限于语言及场景。于是，好奇，既然Java有，那Python也应该有类似的玩法。还真让我给找到了类似的实现。
原文在此：https://jeremykao.wordpress.com/2015/06/10/pagefactory-pattern-in-python/
于是，就借助谷歌翻译加代码运行，弄懂了这哥们想要利用PageFactory 模式实现个什么东西，为了便于你的理解，我这里搬运过来给下结论。
selenium in python中的元素定位是这样的：
find_element_by_id("kw") find_element_by_xpath("//*[@id='kw']")
或者是这样的：
from selenium.webdriver.common.by import By find_element(By.ID,"kw") find_element(By.XPATH,"//*[@id='kw']")
通过PageFactory 模式的实现可以把元素定位变成这样的：
from pageobject_support import callable_find_by as find_by find_by(id_="kw") find_by(xpath="//*[@id='kw']")
别看小小的改动，它其实使代码更容易的阅读和理解。
核心实现就是pageobject_support.py文件：
__all__ = ['cacheable', 'callable_find_by', 'property_find_by'] def cacheable_decorator(lookup): def func(self): if not hasattr(self, '_elements_cache'): self._elements_cache = {} # {callable_id: element(s)} cache = self._elements_cache key = id(lookup) if key not in cache: cache[key] = lookup(self) return cache[key] return func cacheable = cacheable_decorator _strategy_kwargs = ['id_', 'xpath', 'link_text', 'partial_link_text', 'name', 'tag_name', 'class_name', 'css_selector'] def _callable_find_by(how, using, multiple, cacheable, context, driver_attr, **kwargs): def func(self): # context - driver or a certain element if context: ctx = context() if callable(context) else context.__get__(self) # or property else: ctx = getattr(self, driver_attr) # 'how' AND 'using' take precedence over keyword arguments if how and using: lookup = ctx.find_elements if multiple else ctx.find_element return lookup(how, using) if len(kwargs) != 1 or kwargs.keys()[0] not in _strategy_kwargs : raise ValueError( "If 'how' AND 'using' are not specified, one and only one of the following " "valid keyword arguments should be provided: %s." % _strategy_kwargs) key = kwargs.keys()[0]; value = kwargs[key] suffix = key[:-1] if key.endswith('_') else key # find_element(s)_by_xxx prefix = 'find_elements_by' if multiple else 'find_element_by' lookup = getattr(ctx, '%s_%s' % (prefix, suffix)) return lookup(value) return cacheable_decorator(func) if cacheable else func def callable_find_by(how=None, using=None, multiple=False, cacheable=False, context=None, driver_attr='_driver', **kwargs): return _callable_find_by(how, using, multiple, cacheable, context, driver_attr, **kwargs) def property_find_by(how=None, using=None, multiple=False, cacheable=False, context=None, driver_attr='_driver', **kwargs): return property(_callable_find_by(how, using, multiple, cacheable, context, driver_attr, **kwargs))
然后，我再帖一下具体的例子：
from pageobject_support import callable_find_by as find_by from selenium import webdriver class BaiduSearchPage(object): def __init__(self, driver): self._driver = driver search_box = find_by(id_="kw") search_button = find_by(id_='su') def search(self, keywords): self.search_box().clear() self.search_box().send_keys(keywords) self.search_button().click() if __name__ == '__main__': driver = webdriver.Chrome() driver.get("https://www.baidu.com") BaiduSearchPage(driver).search("selenium") driver.close()
同样封装了8种定位方法：
- id_ (为避免与内置的关键字ID冲突，所以多了个下划线的后缀)
- name
- class_name
- css_selector
- tag_name
- xpath
- link_text
- partial_link_text
当然，这只是PageFactory 模式的一种表现形式而已。除此之外，我还找到了另外一个PageFactory模式的例子。
https://github.com/mattfair/SeleniumFactory-for-Python
这哥们是利用PageFactory模式把驱动的创建做了封装，感兴趣可以了解一下。
搬运完了，准备过年。新年快了~！！！
