from urllib import request, parse
from urllib.error import HTTPError,URLError
#保存cookie
from http import cookiejar

class session(object):
    def __init__(self):
        cookie_object = cookiejar.CookieJar()

        handler = request.HTTPCookieProcessor(cookie_object)

        self.opener = request .build_opener(handler)
        #每次遇到cookie的时候 都存储到cookie object

    def get(self, url, headers=None):
        return get(url, headers, self.opener)

    def post(self, url, form, headers=None):
        return post(url, form, headers, self.opener)

def get(url,headers=None,opener=None):
    return urlrequests(url, headers=headers,opener= opener)

def opst(url,form,headers=None,opener=None):
    return urlrequests(url, form, headers=headers, opener=opener)

def urlrequests(url,form=None, headers=None,opener = None):
    user_agent ='Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36'
    if headers == None:
        headers = {
            'User-Agent': user_agent
        }
    html_bytes = b''

    try:
        if form:
            form_str= parse.urlencode(form, encoding='utf-8')

            form_bytes= form_str.encode('utf-8')

            req = request.Request(url, data = form_bytes,headers=headers)

        else:
            req = request.Request(url, headers=headers)
        if opener:
            response= opener.open(req)
        else:
            respones = request,urlopen(req)

        html_bytes = reaponse.read()

    except HTTPError as e:
        print(e)
    except URLError as e:
        print(e)

    retrun html_bytes

if __name__ == '__main__':

    url = 'http://www.baidu.com'
    html_byte = get(url)
    print(html_byte)