3 @copyright: (c) 2005 by Szoftver Messias Bt.
6 Objects of the MozillaEmulator class can emulate a browser that is capable of:
9 - configurable user agent string
11 - multipart POST (send files)
12 - receive content into file
14 I have seen many requests on the python mailing list about how to emulate a browser. I'm using this class for years now, without any problems. This is how you can use it:
17 2. Install and open the livehttpheaders plugin
18 3. Use the website manually with firefox
19 4. Check the GET and POST requests in the livehttpheaders capture window
20 5. Create an instance of the above class and send the same GET and POST requests to the server.
24 - You can change user agent string in the build_opened method
25 - The "encode_multipart_formdata" function can be used alone to create POST data from a list of field values and files
35 _moduleLogger = logging.getLogger(__name__)
36 socket.setdefaulttimeout(30)
39 class MozillaEmulator(object):
41 def __init__(self, trycount = 1):
42 """Create a new MozillaEmulator object.
44 @param trycount: The download() method will retry the operation if it
45 fails. You can specify -1 for infinite retrying. A value of 0 means no
46 retrying. A value of 1 means one retry. etc."""
48 self.trycount = trycount
49 self._cookies = cookielib.LWPCookieJar()
50 self._loadedFromCookies = False
52 def load_cookies(self, path):
53 assert not self._loadedFromCookies, "Load cookies only once"
57 self._cookies.filename = path
60 except cookielib.LoadError:
61 _moduleLogger.exception("Bad cookie file")
63 _moduleLogger.exception("No cookie file")
65 _moduleLogger.exception("Unknown error with cookies")
67 self._loadedFromCookies = True
69 return self._loadedFromCookies
71 def save_cookies(self):
72 if self._loadedFromCookies:
75 def clear_cookies(self):
76 if self._loadedFromCookies:
79 def download(self, url,
80 postdata = None, extraheaders = None, forbidRedirect = False,
81 trycount = None, only_head = False,
83 """Download an URL with GET or POST methods.
85 @param postdata: It can be a string that will be POST-ed to the URL.
86 When None is given, the method will be GET instead.
87 @param extraheaders: You can add/modify HTTP headers with a dict here.
88 @param forbidRedirect: Set this flag if you do not want to handle
89 HTTP 301 and 302 redirects.
90 @param trycount: Specify the maximum number of retries here.
91 0 means no retry on error. Using -1 means infinite retring.
92 None means the default value (that is self.trycount).
93 @param only_head: Create the openerdirector and return it. In other
94 words, this will not retrieve any content except HTTP headers.
96 @return: The raw HTML page data
98 _moduleLogger.debug("Performing download of %s" % url)
100 if extraheaders is None:
103 trycount = self.trycount
108 req, u = self._build_opener(url, postdata, extraheaders, forbidRedirect)
109 openerdirector = u.open(req)
111 _moduleLogger.info("%r - %r" % (req.get_method(), url))
112 _moduleLogger.info("%r - %r" % (openerdirector.code, openerdirector.msg))
113 _moduleLogger.info("%r" % (openerdirector.headers))
114 self._cookies.extract_cookies(openerdirector, req)
116 return openerdirector
118 return self._read(openerdirector, trycount)
119 except urllib2.URLError, e:
120 _moduleLogger.debug("%s: %s" % (e, url))
122 if (-1 < trycount) and (trycount < cnt):
126 _moduleLogger.debug("MozillaEmulator: urllib2.URLError, retrying %d" % cnt)
128 def _build_opener(self, url, postdata = None, extraheaders = None, forbidRedirect = False):
129 if extraheaders is None:
133 'Accept': 'text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png',
134 'Accept-Language': 'en,en-us;q=0.5',
135 'Accept-Charset': 'ISO-8859-1,utf-8;q=0.7,*;q=0.7',
137 for key, value in extraheaders.iteritems():
138 txheaders[key] = value
139 req = urllib2.Request(url, postdata, txheaders)
140 self._cookies.add_cookie_header(req)
142 redirector = HTTPNoRedirector()
143 #_moduleLogger.info("Redirection disabled")
145 redirector = urllib2.HTTPRedirectHandler()
146 #_moduleLogger.info("Redirection enabled")
148 http_handler = urllib2.HTTPHandler(debuglevel=self.debug)
149 https_handler = urllib2.HTTPSHandler(debuglevel=self.debug)
151 u = urllib2.build_opener(
154 urllib2.HTTPCookieProcessor(self._cookies),
159 'Mozilla/5.0 (Windows; U; Windows NT 5.1; de; rv:1.9.1.4) Gecko/20091016 Firefox/3.5.4 (.NET CLR 3.5.30729)'
161 if not postdata is None:
162 req.add_data(postdata)
165 def _read(self, openerdirector, trycount):
168 chunk = openerdirector.read()
170 #while chunk and cnt < trycount:
173 # chunk = openerdirector.read()
174 # chunks.append(chunk)
176 data = "".join(chunks)
178 if "Content-Length" in openerdirector.info():
179 assert len(data) == int(openerdirector.info()["Content-Length"]), "The packet header promised %s of data but only was able to read %s of data" % (
180 openerdirector.info()["Content-Length"],
187 class HTTPNoRedirector(urllib2.HTTPRedirectHandler):
188 """This is a custom http redirect handler that FORBIDS redirection."""
190 def http_error_302(self, req, fp, code, msg, headers):
191 e = urllib2.HTTPError(req.get_full_url(), code, msg, headers, fp)
192 if e.code in (301, 302):
193 if 'location' in headers:
194 newurl = headers.getheaders('location')[0]
195 elif 'uri' in headers:
196 newurl = headers.getheaders('uri')[0]
198 _moduleLogger.info("New url: %s" % e.newurl)