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("gvoice.browser_emu")
36 socket.setdefaulttimeout(10)
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 fails. You can specify -1 for infinite retrying.
45 A value of 0 means no retrying. A value of 1 means one retry. etc."""
47 self.trycount = trycount
48 self._cookies = cookielib.LWPCookieJar()
49 self._loadedFromCookies = False
51 def load_cookies(self, path):
52 assert not self._loadedFromCookies, "Load cookies only once"
56 self._cookies.filename = path
59 except cookielib.LoadError:
60 _moduleLogger.exception("Bad cookie file")
62 _moduleLogger.exception("No cookie file")
64 _moduleLogger.exception("Unknown error with cookies")
66 self._loadedFromCookies = True
68 return self._loadedFromCookies
70 def save_cookies(self):
71 if self._loadedFromCookies:
74 def clear_cookies(self):
75 if self._loadedFromCookies:
78 def download(self, url,
79 postdata = None, extraheaders = None, forbidRedirect = False,
80 trycount = None, only_head = False,
82 """Download an URL with GET or POST methods.
84 @param postdata: It can be a string that will be POST-ed to the URL.
85 When None is given, the method will be GET instead.
86 @param extraheaders: You can add/modify HTTP headers with a dict here.
87 @param forbidRedirect: Set this flag if you do not want to handle
88 HTTP 301 and 302 redirects.
89 @param trycount: Specify the maximum number of retries here.
90 0 means no retry on error. Using -1 means infinite retring.
91 None means the default value (that is self.trycount).
92 @param only_head: Create the openerdirector and return it. In other
93 words, this will not retrieve any content except HTTP headers.
95 @return: The raw HTML page data
97 _moduleLogger.info("Performing download of %s" % url)
99 if extraheaders is None:
102 trycount = self.trycount
107 req, u = self._build_opener(url, postdata, extraheaders, forbidRedirect)
108 openerdirector = u.open(req)
110 _moduleLogger.info("%r - %r" % (req.get_method(), url))
111 _moduleLogger.info("%r - %r" % (openerdirector.code, openerdirector.msg))
112 _moduleLogger.info("%r" % (openerdirector.headers))
113 self._cookies.extract_cookies(openerdirector, req)
115 return openerdirector
117 return self._read(openerdirector, trycount)
118 except urllib2.URLError, e:
119 _moduleLogger.info("%s: %s" % (e, url))
121 if (-1 < trycount) and (trycount < cnt):
125 _moduleLogger.info("MozillaEmulator: urllib2.URLError, retrying %d" % cnt)
127 def _build_opener(self, url, postdata = None, extraheaders = None, forbidRedirect = False):
128 if extraheaders is None:
132 'Accept': 'text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png',
133 'Accept-Language': 'en,en-us;q=0.5',
134 'Accept-Charset': 'ISO-8859-1,utf-8;q=0.7,*;q=0.7',
136 for key, value in extraheaders.iteritems():
137 txheaders[key] = value
138 req = urllib2.Request(url, postdata, txheaders)
139 self._cookies.add_cookie_header(req)
141 redirector = HTTPNoRedirector()
142 #_moduleLogger.info("Redirection disabled")
144 redirector = urllib2.HTTPRedirectHandler()
145 #_moduleLogger.info("Redirection enabled")
147 http_handler = urllib2.HTTPHandler(debuglevel=self.debug)
148 https_handler = urllib2.HTTPSHandler(debuglevel=self.debug)
150 u = urllib2.build_opener(
153 urllib2.HTTPCookieProcessor(self._cookies),
158 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.8) Gecko/20050511 Firefox/1.0.4'
160 if not postdata is None:
161 req.add_data(postdata)
164 def _read(self, openerdirector, trycount):
167 chunk = openerdirector.read()
169 #while chunk and cnt < trycount:
172 # chunk = openerdirector.read()
173 # chunks.append(chunk)
175 data = "".join(chunks)
177 if "Content-Length" in openerdirector.info():
178 assert len(data) == int(openerdirector.info()["Content-Length"]), "The packet header promised %s of data but only was able to read %s of data" % (
179 openerdirector.info()["Content-Length"],
186 class HTTPNoRedirector(urllib2.HTTPRedirectHandler):
187 """This is a custom http redirect handler that FORBIDS redirection."""
189 def http_error_302(self, req, fp, code, msg, headers):
190 e = urllib2.HTTPError(req.get_full_url(), code, msg, headers, fp)
191 if e.code in (301, 302):
192 if 'location' in headers:
193 newurl = headers.getheaders('location')[0]
194 elif 'uri' in headers:
195 newurl = headers.getheaders('uri')[0]
197 _moduleLogger.info("New url: %s" % e.newurl)