Python 请求和持久会话

问题描述：

我正在使用requests模块。我已经弄清楚了如何向网站上的登录表单提交数据并检索会话密钥，但我看不出在后续请求中使用此会话密钥的明显方法。有人可以填写下面代码中的省略号或建议另一种方法吗？

>>> import requests
>>> login_data =  {'formPosted': '1', 'login_email': 'me@example.com', 'password': 'pw'}
>>> r = requests.post('https://localhost/login.py', login_data)
>>> 
>>> r.text
'You are being redirected <a href="profilePage?_ck=1349394964">here</a>'
>>> r.cookies
{'session_id_myapp': '127-0-0-1-825ff22a-6ed1-453b-aebc-5d3cf2987065'}
>>> 
>>> r2 = requests.get('https://localhost/profile_data.json', ...)

解决方案 1：

您可以使用以下方式轻松创建持久会话：

s = requests.Session()

此后，请按照如下方式继续您的请求：

s.post('https://localhost/login.py', login_data)
# logged in! cookies saved for future requests.
r2 = s.get('https://localhost/profile_data.json', ...)
# cookies sent automatically!
# do whatever, s will keep your cookies intact :)

有关Sessions 的更多信息： https: //requests.readthedocs.io/en/latest/user/advanced/#session-objects

解决方案 2：

其他答案有助于理解如何维护这样的会话。此外，我想提供一个类，该类可以在脚本的不同运行中保持会话（使用缓存文件）。这意味着只有在需要时（超时后或缓存中不存在会话时）才会执行正确的“登录”。它还支持对“get”或“post”的后续调用进行代理设置。

已用 Python3 测试。

将其用作您自己的代码的基础。以下代码片段以 GPL v3 发布

import pickle
import datetime
import os
from urllib.parse import urlparse
import requests    

class MyLoginSession:
    """
    a class which handles and saves login sessions. It also keeps track of proxy settings.
    It does also maintine a cache-file for restoring session data from earlier
    script executions.
    """
    def __init__(self,
                 loginUrl,
                 loginData,
                 loginTestUrl,
                 loginTestString,
                 sessionFileAppendix = '_session.dat',
                 maxSessionTimeSeconds = 30 * 60,
                 proxies = None,
                 userAgent = 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.1',
                 debug = True,
                 forceLogin = False,
                 **kwargs):
        """
        save some information needed to login the session

        you'll have to provide 'loginTestString' which will be looked for in the
        responses html to make sure, you've properly been logged in

        'proxies' is of format { 'https' : 'https://user:pass@server:port', 'http' : ...
        'loginData' will be sent as post data (dictionary of id : value).
        'maxSessionTimeSeconds' will be used to determine when to re-login.
        """
        urlData = urlparse(loginUrl)

        self.proxies = proxies
        self.loginData = loginData
        self.loginUrl = loginUrl
        self.loginTestUrl = loginTestUrl
        self.maxSessionTime = maxSessionTimeSeconds
        self.sessionFile = urlData.netloc + sessionFileAppendix
        self.userAgent = userAgent
        self.loginTestString = loginTestString
        self.debug = debug

        self.login(forceLogin, **kwargs)

    def modification_date(self, filename):
        """
        return last file modification date as datetime object
        """
        t = os.path.getmtime(filename)
        return datetime.datetime.fromtimestamp(t)

    def login(self, forceLogin = False, **kwargs):
        """
        login to a session. Try to read last saved session from cache file. If this fails
        do proper login. If the last cache access was too old, also perform a proper login.
        Always updates session cache file.
        """
        wasReadFromCache = False
        if self.debug:
            print('loading or generating session...')
        if os.path.exists(self.sessionFile) and not forceLogin:
            time = self.modification_date(self.sessionFile)         

            # only load if file less than 30 minutes old
            lastModification = (datetime.datetime.now() - time).seconds
            if lastModification < self.maxSessionTime:
                with open(self.sessionFile, "rb") as f:
                    self.session = pickle.load(f)
                    wasReadFromCache = True
                    if self.debug:
                        print("loaded session from cache (last access %ds ago) "
                              % lastModification)
        if not wasReadFromCache:
            self.session = requests.Session()
            self.session.headers.update({'user-agent' : self.userAgent})
            res = self.session.post(self.loginUrl, data = self.loginData, 
                                    proxies = self.proxies, **kwargs)

            if self.debug:
                print('created new session with login' )
            self.saveSessionToCache()

        # test login
        res = self.session.get(self.loginTestUrl)
        if res.text.lower().find(self.loginTestString.lower()) < 0:
            raise Exception("could not log into provided site '%s'"
                            " (did not find successful login string)"
                            % self.loginUrl)

    def saveSessionToCache(self):
        """
        save session to a cache file
        """
        # always save (to update timeout)
        with open(self.sessionFile, "wb") as f:
            pickle.dump(self.session, f)
            if self.debug:
                print('updated session cache-file %s' % self.sessionFile)

    def retrieveContent(self, url, method = "get", postData = None, **kwargs):
        """
        return the content of the url with respect to the session.

        If 'method' is not 'get', the url will be called with 'postData'
        as a post request.
        """
        if method == 'get':
            res = self.session.get(url , proxies = self.proxies, **kwargs)
        else:
            res = self.session.post(url , data = postData, proxies = self.proxies, **kwargs)

        # the session has been updated on the server, so also update in cache
        self.saveSessionToCache()            

        return res

使用上述类的代码片段可能如下所示：

if __name__ == "__main__":
    # proxies = {'https' : 'https://user:pass@server:port',
    #           'http' : 'http://user:pass@server:port'}

    loginData = {'user' : 'usr',
                 'password' :  'pwd'}

    loginUrl = 'https://...'
    loginTestUrl = 'https://...'
    successStr = 'Hello Tom'
    s = MyLoginSession(loginUrl, loginData, loginTestUrl, successStr, 
                       #proxies = proxies
                       )
    
    res = s.retrieveContent('https://....')
    print(res.text)

    # if, for instance, login via JSON values required try this:
    s = MyLoginSession(loginUrl, None, loginTestUrl, successStr, 
                       #proxies = proxies,
                       json = loginData)
    

解决方案 3：

看看我在这个类似问题中的回答：

python：urllib2 如何使用 urlopen 请求发送 cookie

import urllib2
import urllib
from cookielib import CookieJar

cj = CookieJar()
opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
# input-type values from the html form
formdata = { "username" : username, "password": password, "form-id" : "1234" }
data_encoded = urllib.urlencode(formdata)
response = opener.open("https://page.com/login.php", data_encoded)
content = response.read()

编辑：

我看到我的回答得到了一些反对票，但没有解释性评论。我猜是因为我指的是urllib库而不是requests。我这样做是因为 OP 请求帮助requests或请求某人建议另一种方法。

解决方案 4：

文档说，它get接受一个可选cookies参数，允许您指定要使用的 cookie：

来自文档：

>>> url = 'http://httpbin.org/cookies'
>>> cookies = dict(cookies_are='working')

>>> r = requests.get(url, cookies=cookies)
>>> r.text
'{"cookies": {"cookies_are": "working"}}'

http://docs.python-requests.org/en/latest/user/quickstart/#cookies

解决方案 5：

尝试了上述所有答案后，我发现在后续请求中使用“RequestsCookieJar”而不是常规的 CookieJar 可以解决我的问题。

import requests
import json

# The Login URL
authUrl = 'https://whatever.com/login'

# The subsequent URL
testUrl = 'https://whatever.com/someEndpoint'

# Logout URL
testlogoutUrl = 'https://whatever.com/logout'

# Whatever you are posting
login_data =  {'formPosted':'1', 
               'login_email':'me@example.com', 
               'password':'pw'
               }

# The Authentication token or any other data that we will receive from the Authentication Request. 
token = ''

# Post the login Request
loginRequest = requests.post(authUrl, login_data)
print("{}".format(loginRequest.text))

# Save the request content to your variable. In this case I needed a field called token. 
token = str(json.loads(loginRequest.content)['token'])  # or ['access_token']
print("{}".format(token))

# Verify Successful login
print("{}".format(loginRequest.status_code))

# Create your Requests Cookie Jar for your subsequent requests and add the cookie
jar = requests.cookies.RequestsCookieJar()
jar.set('LWSSO_COOKIE_KEY', token)

# Execute your next request(s) with the Request Cookie Jar set
r = requests.get(testUrl, cookies=jar)
print("R.TEXT: {}".format(r.text))
print("R.STCD: {}".format(r.status_code))

# Execute your logout request(s) with the Request Cookie Jar set
r = requests.delete(testlogoutUrl, cookies=jar)
print("R.TEXT: {}".format(r.text))  # should show "Request Not Authorized"
print("R.STCD: {}".format(r.status_code))  # should show 401

解决方案 6：

仅保存所需的 cookie 并重复使用它们。

import os
import pickle
from urllib.parse import urljoin, urlparse

login = 'my@email.com'
password = 'secret'
# Assuming two cookies are used for persistent login.
# (Find it by tracing the login process)
persistentCookieNames = ['sessionId', 'profileId']
URL = 'http://example.com'
urlData = urlparse(URL)
cookieFile = urlData.netloc + '.cookie'
signinUrl = urljoin(URL, "/signin")
with requests.Session() as session:
    try:
        with open(cookieFile, 'rb') as f:
            print("Loading cookies...")
            session.cookies.update(pickle.load(f))
    except Exception:
        # If could not load cookies from file, get the new ones by login in
        print("Login in...")
        post = session.post(
            signinUrl,
            data={
                'email': login,
                'password': password,
            }
        )
        try:
            with open(cookieFile, 'wb') as f:
                jar = requests.cookies.RequestsCookieJar()
                for cookie in session.cookies:
                    if cookie.name in persistentCookieNames:
                        jar.set_cookie(cookie)
                pickle.dump(jar, f)
        except Exception as e:
            os.remove(cookieFile)
            raise(e)
    MyPage = urljoin(URL, "/mypage")
    page = session.get(MyPage)

解决方案 7：

用于检索 json 数据的代码片段，受密码保护

import requests

username = "my_user_name"
password = "my_super_secret"
url = "https://www.my_base_url.com"
the_page_i_want = "/my_json_data_page"

session = requests.Session()
# retrieve cookie value
resp = session.get(url+'/login')
csrf_token = resp.cookies['csrftoken']
# login, add referer
resp = session.post(url+"/login",
                  data={
                      'username': username,
                      'password': password,
                      'csrfmiddlewaretoken': csrf_token,
                      'next': the_page_i_want,
                  },
                  headers=dict(Referer=url+"/login"))
print(resp.json())

解决方案 8：

这将在 Python 中为您工作；

# Call JIRA API with HTTPBasicAuth
import json
import requests
from requests.auth import HTTPBasicAuth

JIRA_EMAIL = "****"
JIRA_TOKEN = "****"
BASE_URL = "https://****.atlassian.net"
API_URL = "/rest/api/3/serverInfo"

API_URL = BASE_URL+API_URL

BASIC_AUTH = HTTPBasicAuth(JIRA_EMAIL, JIRA_TOKEN)
HEADERS = {'Content-Type' : 'application/json;charset=iso-8859-1'}

response = requests.get(
    API_URL,
    headers=HEADERS,
    auth=BASIC_AUTH
)

print(json.dumps(json.loads(response.text), sort_keys=True, indent=4, separators=(",", ": ")))