Python FileCookieJar.save() 问题

Question

我在用 FileCookieJar 的 save 方法保存 cookies 到文件时遇到了问题。以下是我的代码：

#!/usr/bin/python
import httplib, cookielib, urllib2, json, time
from datetime import date


class FoN:
    def __init__(self):
            self.cookiefile = "cookies.txt"
            self.cj = cookielib.FileCookieJar(self.cookiefile)
    def login (self, login, password):
            js = json.JSONEncoder().encode({"login":login,"password":password})
            req=urllib2.Request("http://www.example.com/user/login", js)
            res=urllib2.urlopen(req)
            self.cj.extract_cookies(res,req)
            self.cj.save(self.cookiefile, ignore_discard=True)
            f.write ("Login: "+login+", result: "+str(res.read().count("true"))+"\n")
            time.sleep(2)
            return res

问题出在 self.cj.save(self.cookiefile, ignore_discard=True) 这一行，它抛出了一个 NotImplementedError 的异常，这在文档中有说明。但是我想知道，我该怎么把 cookies 保存到文件呢？我甚至尝试把这段代码放在 try 语句里，但完全没有帮助。

Answer 1

我写了一段示例代码来演示：

• 自动处理 cookies：在 内存 中的 cookie
• 自动处理 cookies：在 文件 中的 cookie
  • 支持两种格式：
    • LWP
    • Mozilla
  • 两种操作方式
    • 保存到文件
    • 从文件加载

代码：

    #!/usr/bin/python
    # -*- coding: utf-8 -*-
    """
    Function:   【整理】Python中Cookie的处理：自动处理Cookie，保存为Cookie文件，从文件载入Cookie
                http://www.crifan.com/python_auto_handle_cookie_and_save_to_from_cookie_file

    Version:    2013-01-15
    Author:     Crifan
    Contact:    admin (at) crifan.com
    """

    import os;
    import cookielib;
    import urllib2;

    def pythonAutoHandleCookie():
        """
            Demo how to auto handle cookie in Python
                cookies in memory
                cookies in file:
                    save cookie to file
                        LWP     format
                        Mozilla format
                    load cookie from file
        """

        print "1. Demo how to auto handle cookie (in memory)";
        cookieJarInMemory = cookielib.CookieJar();
        opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookieJarInMemory));
        urllib2.install_opener(opener);
        print "after init, cookieJarInMemory=",cookieJarInMemory; #after init, cookieJarInMemory= 
        #!!! following urllib2 will auto handle cookies
        demoUrl = "http://www.google.com/";
        response = urllib2.urlopen(demoUrl);
        #here, we already got response cookies
        print "after urllib2.urlopen, cookieJarInMemory=",cookieJarInMemory;
        #after urllib2.urlopen, cookieJarInMemory= , , ]>


        print "2. Demo how to auto handle cookie in file, LWP format";
        cookieFilenameLWP = "localCookiesLWP.txt";
        cookieJarFileLWP = cookielib.LWPCookieJar(cookieFilenameLWP);
        #will create (and save to) new cookie file
        cookieJarFileLWP.save();
        opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookieJarFileLWP));
        urllib2.install_opener(opener);
        #!!! following urllib2 will auto handle cookies
        demoUrl = "http://www.google.com/";
        response = urllib2.urlopen(demoUrl);
        #update cookies, save cookies into file
        cookieJarFileLWP.save();
        #for demo, print cookies in file
        print "LWP cookies:";
        print open(cookieFilenameLWP).read(os.path.getsize(cookieFilenameLWP));
        # #LWP-Cookies-2.0
        # Set-Cookie3: PREF="ID=34c1415b570a93ae:FF=0:NW=1:TM=1358236121:LM=1358236121:S=gEVVojW4x37ht5n-"; path="/"; domain=".google.com"; path_spec; domain_dot; expires="2015-01-15 07:48:41Z"; version=0
        # Set-Cookie3: NID="67=JI_uEwUm5GDrQ_vCwAp2z_YGU7MdLm5CLMa4CNLF7RQuTDMzrrk1EjRddGcnpoFbht81LaV9spxZQQInf0mPS6lDrvcRqBBL5NOTmy8SwOzA6HWC3iTIo4-o3fO1Udkv"; path="/"; domain=".google.com.hk"; path_spec; domain_dot; expires="2013-07-17 07:48:41Z"; HttpOnly=None; version=0
        # Set-Cookie3: PREF="ID=8f7e4efca89bdb1b:U=f85a4afa4db021aa:FF=2:LD=zh-CN:NW=1:TM=1358236121:LM=1358236121:S=2WR59hDWutdnUJtF"; path="/"; domain=".google.com.hk"; path_spec; domain_dot; expires="2015-01-15 07:48:41Z"; version=0

        print "3. Demo how to auto handle cookie in file, Mozilla Format";
        cookieFilenameMozilla = "localCookiesMozilla.txt";
        cookieJarFileMozilla = cookielib.MozillaCookieJar(cookieFilenameMozilla);
        #will create (and save to) new cookie file
        cookieJarFileMozilla.save();
        opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookieJarFileMozilla));
        urllib2.install_opener(opener);
        #!!! following urllib2 will auto handle cookies
        demoUrl = "http://www.google.com/";
        response = urllib2.urlopen(demoUrl);
        #update cookies, save cookies into file
        cookieJarFileMozilla.save();
        #for demo, print cookies in file
        print "Mozilla cookies:";
        print open(cookieFilenameMozilla).read(os.path.getsize(cookieFilenameMozilla));
        # # Netscape HTTP Cookie File
        # # http://www.netscape.com/newsref/std/cookie_spec.html
        # # This is a generated file!  Do not edit.

        # .google.com   TRUE    /   FALSE   1421308121  PREF    ID=0e05040dd979207c:FF=0:NW=1:TM=1358236121:LM=1358236121:S=jcFid2XgXMIhPUPl
        # .google.com.hk    TRUE    /   FALSE   1374047321  NID 67=klMI_Z5ZPWDjUYrWSUHIE_kYI77_ziJaL0kWRoUGThagME86LKY7H-MNa2wAMI_GklIwYcD8t82qPinxzLd4GLDbmWT0OVLCXhRj0wQDC57dTNAsTs4lhVR7Yjvj2tfn
        # .google.com.hk    TRUE    /   FALSE   1421308121  PREF    ID=028f8b736db06a9a:U=6ba6d080847c8de6:FF=2:LD=zh-CN:NW=1:TM=1358236121:LM=1358236121:S=_1BcC5v3G0ZojVz8

        print "4. read cookies from file";
        parseAndSavedCookieFile = "parsedAndSavedCookies.txt"
        parsedCookieJarFile = cookielib.MozillaCookieJar(parseAndSavedCookieFile);
        #parsedCookieJarFile = cookielib.MozillaCookieJar(cookieFilenameMozilla);
        print parsedCookieJarFile; #
        parsedCookieJarFile.load(cookieFilenameMozilla);
        print parsedCookieJarFile; #, , ]>


    if __name__=="__main__":
        pythonAutoHandleCookie();

Answer 2

基础的 FileCookieJar 并没有实现 .save 这个功能。如果你想要保存数据，应该使用它的子类，比如 MozillaCookieJar 或者 LWPCookieJar。