selenium 和 lxml - 如何设置 html?

selenium and lxml - how to set html?

我有一个脚本可以解析文档并使用 lxml 更改表单值。现在我想使用selenium导航到页面并执行它。

不幸的是,selenium 似乎不够先进,无法支持我在 lxml 中做的一些事情,例如,"if 'attrName' in tag.attrib"

然后我说,"Aha!, But selenium provides webdriver.page_source where I can get the html!" 是的,有点......我可以得到它,然后用 lxml 解析它......但令人讨厌的是,page_source 不可写,所以我无法坚持我的更改!

我仍然觉得我的方向是正确的,但是有什么方法可以将修改后的 html 写回浏览器吗?

更新: 我尝试了几种尝试重写所有页面内容的方法,但是 firefox webdriver 开始抛出安全异常,就像它不喜欢我尝试做的事情一样。下面我将 post 我使用的替代方法。

我最后做的是创建一个类似 lxml 的中介 class。这只实现了我需要的那些功能,但我仍然认为我会作为一个起点分享给其他尝试做同样事情的人。

import lxml.etree
import collections.abc


class AttribWrapper(collections.abc.MutableMapping):
    """
    Make something that acts like a dict to use as a mock lxml.etree.element attrib value

    see also:
        https://docs.python.org/3/reference/datamodel.html?emulating-container-types#emulating-container-types
    """
    def __init__(self,seleniumTag):
        self.seleniumTag=seleniumTag
        while not hasattr(seleniumTag,'execute_script'):
            seleniumTag=seleniumTag.parent
        self.webdriver=seleniumTag

    def hasAttribute(self,attrName):
        """
        determine if a tag has an attribute
        """
        try:
            val=self.seleniumTag.get_attribute(attrName)
        except Exception:
            return False
        return val is not None

    def getAttribute(self,attrName,default=None):
        """
        get a tag's attribute or default if not present
        """
        try:
            return self.seleniumTag.get_attribute(attrName)
        except Exception:
            pass
        return default

    def setAttribute(self,attrName,attrValue):
        """
        get a tag's attribute
        """
        self.webdriver.execute_script("arguments[0].setAttribute(arguments[1],arguments[2]);",self.seleniumTag,attrName,attrValue);

    def __getitem__(self,key):
        if key not in self.keys():
            raise KeyError()
        return self.getAttribute(key)

    def __setitem__(self,key,value):
        self.setAttribute(key,value)

    def __delitem__(self,key):
        self.webdriver.execute_script('arguments[0].attributes.removeNamedItem("%s");'%key,self.seleniumTag)

    def __iter__(self):
        items=[]
        for k in self.keys():
            v=self[k]
            items.append((k,v))
        return self.keys().__iter__()

    def __len__(self):
        return self.webdriver.execute_script('return arguments[0].attributes.length',self.seleniumTag)

    def keys(self):
        n=self.webdriver.execute_script('return arguments[0].attributes.length',self.seleniumTag)
        names=[]
        for idx in range(n):
            result=self.webdriver.execute_script('return arguments[0].attributes.item(%d).nodeName'%idx,self.seleniumTag)
            names.append(result)
        return names

    def __repr__(self):
        ret=[]
        for k,v in self.items():
            ret.append('("%s":"%s")'%(k,v))
        return "{%s}"%(', '.join(ret))


class LikeEtreeElement:

    def __init__(self,seleniumTag):
        self.seleniumTag=seleniumTag
        self.attrib=AttribWrapper(seleniumTag)
        while not hasattr(seleniumTag,'execute_script'):
            seleniumTag=seleniumTag.parent
        self.webdriver=seleniumTag

    @property
    def tag(self):
        return self.seleniumTag.tag_name

    def getchildren(self):
        """
        get all child elements
        (NOTE: this will dip into the html every single time just
            in case things have changed.)
        """
        return self.seleniumTag.find_elements_by_xpath('/*')

    @property     
    def innerHTML(self):
        return self.webdriver.execute_script('return arguments[0].innerHTML',self.seleniumTag)
    @innerHTML.setter
    def innerHTML(self,value):
        value=str(value).replace('\\','\').replace('\n','\n').replace('"','\"')
        return self.webdriver.execute_script('arguments[0].innerHTML="%s"'%(value),self.seleniumTag)

    def __getitem__(self,idx):
        return self.getchildren()[idx]

    def __iter__(self):
        return self.getchildren().__iter__()

    def __len__(self):
        return len(self.getchildren())