Georg Brandl | 8175dae | 2010-11-29 14:53:15 +0000 | [diff] [blame] | 1 | :mod:`urllib.request` --- Extensible library for opening URLs |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 2 | ============================================================= |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 3 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 4 | .. module:: urllib.request |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 5 | :synopsis: Extensible library for opening URLs. |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 6 | .. moduleauthor:: Jeremy Hylton <jeremy@alum.mit.edu> |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 7 | .. sectionauthor:: Moshe Zadka <moshez@users.sourceforge.net> |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 8 | .. sectionauthor:: Senthil Kumaran <senthil@uthcode.com> |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 9 | |
| 10 | |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 11 | The :mod:`urllib.request` module defines functions and classes which help in |
| 12 | opening URLs (mostly HTTP) in a complex world --- basic and digest |
| 13 | authentication, redirections, cookies and more. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 14 | |
Benjamin Peterson | 6de708f | 2015-04-20 18:18:14 -0400 | [diff] [blame] | 15 | .. seealso:: |
| 16 | |
Georg Brandl | 5d94134 | 2016-02-26 19:37:12 +0100 | [diff] [blame^] | 17 | The `Requests package <https://requests.readthedocs.org/>`_ |
Benjamin Peterson | 6de708f | 2015-04-20 18:18:14 -0400 | [diff] [blame] | 18 | is recommended for a higher-level http client interface. |
| 19 | |
Antoine Pitrou | 79ecd76 | 2010-09-29 11:24:21 +0000 | [diff] [blame] | 20 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 21 | The :mod:`urllib.request` module defines the following functions: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 22 | |
| 23 | |
Senthil Kumaran | a5c85b3 | 2014-09-19 15:23:30 +0800 | [diff] [blame] | 24 | .. function:: urlopen(url, data=None[, timeout], *, cafile=None, capath=None, cadefault=False, context=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 25 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 26 | Open the URL *url*, which can be either a string or a |
| 27 | :class:`Request` object. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 28 | |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 29 | *data* must be a bytes object specifying additional data to be sent to the |
Senthil Kumaran | 7bc0d87 | 2010-12-19 10:49:52 +0000 | [diff] [blame] | 30 | server, or ``None`` if no such data is needed. *data* may also be an |
| 31 | iterable object and in that case Content-Length value must be specified in |
| 32 | the headers. Currently HTTP requests are the only ones that use *data*; the |
| 33 | HTTP request will be a POST instead of a GET when the *data* parameter is |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 34 | provided. |
| 35 | |
| 36 | *data* should be a buffer in the standard |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 37 | :mimetype:`application/x-www-form-urlencoded` format. The |
Senthil Kumaran | 7bc0d87 | 2010-12-19 10:49:52 +0000 | [diff] [blame] | 38 | :func:`urllib.parse.urlencode` function takes a mapping or sequence of |
Martin Panter | cda85a0 | 2015-11-24 22:33:18 +0000 | [diff] [blame] | 39 | 2-tuples and returns an ASCII text string in this format. It should |
| 40 | be encoded to bytes before being used as the *data* parameter. |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 41 | |
| 42 | urllib.request module uses HTTP/1.1 and includes ``Connection:close`` header |
| 43 | in its HTTP requests. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 44 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 45 | The optional *timeout* parameter specifies a timeout in seconds for |
| 46 | blocking operations like the connection attempt (if not specified, |
| 47 | the global default timeout setting will be used). This actually |
Senthil Kumaran | c08d907 | 2010-10-05 18:46:56 +0000 | [diff] [blame] | 48 | only works for HTTP, HTTPS and FTP connections. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 49 | |
Senthil Kumaran | a5c85b3 | 2014-09-19 15:23:30 +0800 | [diff] [blame] | 50 | If *context* is specified, it must be a :class:`ssl.SSLContext` instance |
Benjamin Peterson | a5c9c37 | 2014-11-02 13:17:56 -0500 | [diff] [blame] | 51 | describing the various SSL options. See :class:`~http.client.HTTPSConnection` |
| 52 | for more details. |
Senthil Kumaran | a5c85b3 | 2014-09-19 15:23:30 +0800 | [diff] [blame] | 53 | |
Antoine Pitrou | 803e6d6 | 2010-10-13 10:36:15 +0000 | [diff] [blame] | 54 | The optional *cafile* and *capath* parameters specify a set of trusted |
| 55 | CA certificates for HTTPS requests. *cafile* should point to a single |
| 56 | file containing a bundle of CA certificates, whereas *capath* should |
| 57 | point to a directory of hashed certificate files. More information can |
| 58 | be found in :meth:`ssl.SSLContext.load_verify_locations`. |
| 59 | |
Benjamin Peterson | 378e15d | 2014-11-23 11:43:33 -0600 | [diff] [blame] | 60 | The *cadefault* parameter is ignored. |
Antoine Pitrou | de9ac6c | 2012-05-16 21:40:01 +0200 | [diff] [blame] | 61 | |
Martin Panter | 747d48c | 2015-11-26 11:01:58 +0000 | [diff] [blame] | 62 | This function always returns an object which can work as |
Senthil Kumaran | b98e96a | 2013-02-07 00:47:01 -0800 | [diff] [blame] | 63 | :term:`context manager` and has methods such as |
| 64 | |
| 65 | * :meth:`~urllib.response.addinfourl.geturl` --- return the URL of the resource retrieved, |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 66 | commonly used to determine if a redirect was followed |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 67 | |
Senthil Kumaran | b98e96a | 2013-02-07 00:47:01 -0800 | [diff] [blame] | 68 | * :meth:`~urllib.response.addinfourl.info` --- return the meta-information of the page, such as headers, |
Senthil Kumaran | 13a7eb4 | 2010-06-28 17:31:40 +0000 | [diff] [blame] | 69 | in the form of an :func:`email.message_from_string` instance (see |
| 70 | `Quick Reference to HTTP Headers <http://www.cs.tut.fi/~jkorpela/http.html>`_) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 71 | |
Senthil Kumaran | b98e96a | 2013-02-07 00:47:01 -0800 | [diff] [blame] | 72 | * :meth:`~urllib.response.addinfourl.getcode` -- return the HTTP status code of the response. |
| 73 | |
Martin Panter | 747d48c | 2015-11-26 11:01:58 +0000 | [diff] [blame] | 74 | For http and https urls, this function returns a |
| 75 | :class:`http.client.HTTPResponse` object slightly modified. In addition |
| 76 | to the three new methods above, the msg attribute contains the |
| 77 | same information as the :attr:`~http.client.HTTPResponse.reason` |
| 78 | attribute --- the reason phrase returned by server --- instead of |
| 79 | the response headers as it is specified in the documentation for |
| 80 | :class:`~http.client.HTTPResponse`. |
| 81 | |
| 82 | For ftp, file, and data urls and requests explicitly handled by legacy |
| 83 | :class:`URLopener` and :class:`FancyURLopener` classes, this function |
| 84 | returns a :class:`urllib.response.addinfourl` object. |
| 85 | |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 86 | Raises :exc:`~urllib.error.URLError` on errors. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 87 | |
Georg Brandl | 2dd0104 | 2009-02-27 16:46:46 +0000 | [diff] [blame] | 88 | Note that ``None`` may be returned if no handler handles the request (though |
| 89 | the default installed global :class:`OpenerDirector` uses |
| 90 | :class:`UnknownHandler` to ensure this never happens). |
| 91 | |
R David Murray | 5aea37a | 2013-04-28 11:07:16 -0400 | [diff] [blame] | 92 | In addition, if proxy settings are detected (for example, when a ``*_proxy`` |
| 93 | environment variable like :envvar:`http_proxy` is set), |
| 94 | :class:`ProxyHandler` is default installed and makes sure the requests are |
| 95 | handled through the proxy. |
Senthil Kumaran | a51a1b3 | 2009-10-18 01:42:33 +0000 | [diff] [blame] | 96 | |
Georg Brandl | 2dd0104 | 2009-02-27 16:46:46 +0000 | [diff] [blame] | 97 | The legacy ``urllib.urlopen`` function from Python 2.6 and earlier has been |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 98 | discontinued; :func:`urllib.request.urlopen` corresponds to the old |
| 99 | ``urllib2.urlopen``. Proxy handling, which was done by passing a dictionary |
| 100 | parameter to ``urllib.urlopen``, can be obtained by using |
| 101 | :class:`ProxyHandler` objects. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 102 | |
Antoine Pitrou | 803e6d6 | 2010-10-13 10:36:15 +0000 | [diff] [blame] | 103 | .. versionchanged:: 3.2 |
| 104 | *cafile* and *capath* were added. |
| 105 | |
Antoine Pitrou | d532321 | 2010-10-22 18:19:07 +0000 | [diff] [blame] | 106 | .. versionchanged:: 3.2 |
| 107 | HTTPS virtual hosts are now supported if possible (that is, if |
| 108 | :data:`ssl.HAS_SNI` is true). |
| 109 | |
Senthil Kumaran | 7bc0d87 | 2010-12-19 10:49:52 +0000 | [diff] [blame] | 110 | .. versionadded:: 3.2 |
| 111 | *data* can be an iterable object. |
| 112 | |
Antoine Pitrou | de9ac6c | 2012-05-16 21:40:01 +0200 | [diff] [blame] | 113 | .. versionchanged:: 3.3 |
| 114 | *cadefault* was added. |
| 115 | |
Benjamin Peterson | 4a358de | 2014-11-03 17:04:01 -0500 | [diff] [blame] | 116 | .. versionchanged:: 3.4.3 |
Senthil Kumaran | a5c85b3 | 2014-09-19 15:23:30 +0800 | [diff] [blame] | 117 | *context* was added. |
| 118 | |
Benjamin Peterson | 030dbb9 | 2014-11-02 13:19:15 -0500 | [diff] [blame] | 119 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 120 | .. function:: install_opener(opener) |
| 121 | |
| 122 | Install an :class:`OpenerDirector` instance as the default global opener. |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 123 | Installing an opener is only necessary if you want urlopen to use that |
| 124 | opener; otherwise, simply call :meth:`OpenerDirector.open` instead of |
| 125 | :func:`~urllib.request.urlopen`. The code does not check for a real |
| 126 | :class:`OpenerDirector`, and any class with the appropriate interface will |
| 127 | work. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 128 | |
| 129 | |
| 130 | .. function:: build_opener([handler, ...]) |
| 131 | |
| 132 | Return an :class:`OpenerDirector` instance, which chains the handlers in the |
| 133 | order given. *handler*\s can be either instances of :class:`BaseHandler`, or |
| 134 | subclasses of :class:`BaseHandler` (in which case it must be possible to call |
| 135 | the constructor without any parameters). Instances of the following classes |
| 136 | will be in front of the *handler*\s, unless the *handler*\s contain them, |
R David Murray | 5aea37a | 2013-04-28 11:07:16 -0400 | [diff] [blame] | 137 | instances of them or subclasses of them: :class:`ProxyHandler` (if proxy |
R David Murray | 9330a94 | 2013-04-28 11:24:35 -0400 | [diff] [blame] | 138 | settings are detected), :class:`UnknownHandler`, :class:`HTTPHandler`, |
| 139 | :class:`HTTPDefaultErrorHandler`, :class:`HTTPRedirectHandler`, |
| 140 | :class:`FTPHandler`, :class:`FileHandler`, :class:`HTTPErrorProcessor`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 141 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 142 | If the Python installation has SSL support (i.e., if the :mod:`ssl` module |
| 143 | can be imported), :class:`HTTPSHandler` will also be added. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 144 | |
Georg Brandl | e6bcc91 | 2008-05-12 18:05:20 +0000 | [diff] [blame] | 145 | A :class:`BaseHandler` subclass may also change its :attr:`handler_order` |
Senthil Kumaran | a6bac95 | 2011-07-04 11:28:30 -0700 | [diff] [blame] | 146 | attribute to modify its position in the handlers list. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 147 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 148 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 149 | .. function:: pathname2url(path) |
Christian Heimes | 292d351 | 2008-02-03 16:51:08 +0000 | [diff] [blame] | 150 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 151 | Convert the pathname *path* from the local syntax for a path to the form used in |
| 152 | the path component of a URL. This does not produce a complete URL. The return |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 153 | value will already be quoted using the :func:`~urllib.parse.quote` function. |
Christian Heimes | 292d351 | 2008-02-03 16:51:08 +0000 | [diff] [blame] | 154 | |
| 155 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 156 | .. function:: url2pathname(path) |
| 157 | |
Senthil Kumaran | f0769e8 | 2010-08-09 19:53:52 +0000 | [diff] [blame] | 158 | Convert the path component *path* from a percent-encoded URL to the local syntax for a |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 159 | path. This does not accept a complete URL. This function uses |
| 160 | :func:`~urllib.parse.unquote` to decode *path*. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 161 | |
Senthil Kumaran | 7e557a6 | 2010-02-26 00:53:23 +0000 | [diff] [blame] | 162 | .. function:: getproxies() |
| 163 | |
| 164 | This helper function returns a dictionary of scheme to proxy server URL |
Senthil Kumaran | 19d85c2 | 2012-01-11 01:29:08 +0800 | [diff] [blame] | 165 | mappings. It scans the environment for variables named ``<scheme>_proxy``, |
| 166 | in a case insensitive approach, for all operating systems first, and when it |
| 167 | cannot find it, looks for proxy information from Mac OSX System |
| 168 | Configuration for Mac OS X and Windows Systems Registry for Windows. |
Senthil Kumaran | 7e557a6 | 2010-02-26 00:53:23 +0000 | [diff] [blame] | 169 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 170 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 171 | The following classes are provided: |
| 172 | |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 173 | .. class:: Request(url, data=None, headers={}, origin_req_host=None, unverifiable=False, method=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 174 | |
| 175 | This class is an abstraction of a URL request. |
| 176 | |
| 177 | *url* should be a string containing a valid URL. |
| 178 | |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 179 | *data* must be a bytes object specifying additional data to send to the |
Senthil Kumaran | 87684e6 | 2012-03-14 18:08:13 -0700 | [diff] [blame] | 180 | server, or ``None`` if no such data is needed. Currently HTTP requests are |
| 181 | the only ones that use *data*; the HTTP request will be a POST instead of a |
| 182 | GET when the *data* parameter is provided. *data* should be a buffer in the |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 183 | standard :mimetype:`application/x-www-form-urlencoded` format. |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 184 | The :func:`urllib.parse.urlencode` function takes a mapping or sequence of |
Martin Panter | cda85a0 | 2015-11-24 22:33:18 +0000 | [diff] [blame] | 185 | 2-tuples and returns an ASCII string in this format. It should be |
| 186 | encoded to bytes before being used as the *data* parameter. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 187 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 188 | *headers* should be a dictionary, and will be treated as if |
| 189 | :meth:`add_header` was called with each key and value as arguments. |
| 190 | This is often used to "spoof" the ``User-Agent`` header, which is |
| 191 | used by a browser to identify itself -- some HTTP servers only |
| 192 | allow requests coming from common browsers as opposed to scripts. |
| 193 | For example, Mozilla Firefox may identify itself as ``"Mozilla/5.0 |
| 194 | (X11; U; Linux i686) Gecko/20071127 Firefox/2.0.0.11"``, while |
| 195 | :mod:`urllib`'s default user agent string is |
| 196 | ``"Python-urllib/2.6"`` (on Python 2.6). |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 197 | |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 198 | An example of using ``Content-Type`` header with *data* argument would be |
Martin Panter | cda85a0 | 2015-11-24 22:33:18 +0000 | [diff] [blame] | 199 | sending a dictionary like ``{"Content-Type": "application/x-www-form-urlencoded"}``. |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 200 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 201 | The final two arguments are only of interest for correct handling |
| 202 | of third-party HTTP cookies: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 203 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 204 | *origin_req_host* should be the request-host of the origin |
| 205 | transaction, as defined by :rfc:`2965`. It defaults to |
| 206 | ``http.cookiejar.request_host(self)``. This is the host name or IP |
| 207 | address of the original request that was initiated by the user. |
| 208 | For example, if the request is for an image in an HTML document, |
| 209 | this should be the request-host of the request for the page |
Georg Brandl | 2442015 | 2008-05-26 16:32:26 +0000 | [diff] [blame] | 210 | containing the image. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 211 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 212 | *unverifiable* should indicate whether the request is unverifiable, |
Serhiy Storchaka | fbc1c26 | 2013-11-29 12:17:13 +0200 | [diff] [blame] | 213 | as defined by RFC 2965. It defaults to ``False``. An unverifiable |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 214 | request is one whose URL the user did not have the option to |
| 215 | approve. For example, if the request is for an image in an HTML |
| 216 | document, and the user had no option to approve the automatic |
| 217 | fetching of the image, this should be true. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 218 | |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 219 | *method* should be a string that indicates the HTTP request method that |
Larry Hastings | 3732ed2 | 2014-03-15 21:13:56 -0700 | [diff] [blame] | 220 | will be used (e.g. ``'HEAD'``). If provided, its value is stored in the |
Senthil Kumaran | a41c942 | 2011-10-20 02:37:08 +0800 | [diff] [blame] | 221 | :attr:`~Request.method` attribute and is used by :meth:`get_method()`. |
Jason R. Coombs | 0c47f34 | 2013-09-22 09:33:45 -0400 | [diff] [blame] | 222 | Subclasses may indicate a default method by setting the |
| 223 | :attr:`~Request.method` attribute in the class itself. |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 224 | |
| 225 | .. versionchanged:: 3.3 |
Georg Brandl | 61063cc | 2012-06-24 22:48:30 +0200 | [diff] [blame] | 226 | :attr:`Request.method` argument is added to the Request class. |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 227 | |
Jason R. Coombs | 0c47f34 | 2013-09-22 09:33:45 -0400 | [diff] [blame] | 228 | .. versionchanged:: 3.4 |
| 229 | Default :attr:`Request.method` may be indicated at the class level. |
| 230 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 231 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 232 | .. class:: OpenerDirector() |
| 233 | |
| 234 | The :class:`OpenerDirector` class opens URLs via :class:`BaseHandler`\ s chained |
| 235 | together. It manages the chaining of handlers, and recovery from errors. |
| 236 | |
| 237 | |
| 238 | .. class:: BaseHandler() |
| 239 | |
| 240 | This is the base class for all registered handlers --- and handles only the |
| 241 | simple mechanics of registration. |
| 242 | |
| 243 | |
| 244 | .. class:: HTTPDefaultErrorHandler() |
| 245 | |
| 246 | A class which defines a default handler for HTTP error responses; all responses |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 247 | are turned into :exc:`~urllib.error.HTTPError` exceptions. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 248 | |
| 249 | |
| 250 | .. class:: HTTPRedirectHandler() |
| 251 | |
| 252 | A class to handle redirections. |
| 253 | |
| 254 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 255 | .. class:: HTTPCookieProcessor(cookiejar=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 256 | |
| 257 | A class to handle HTTP Cookies. |
| 258 | |
| 259 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 260 | .. class:: ProxyHandler(proxies=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 261 | |
| 262 | Cause requests to go through a proxy. If *proxies* is given, it must be a |
R David Murray | 9330a94 | 2013-04-28 11:24:35 -0400 | [diff] [blame] | 263 | dictionary mapping protocol names to URLs of proxies. The default is to read |
| 264 | the list of proxies from the environment variables |
| 265 | :envvar:`<protocol>_proxy`. If no proxy environment variables are set, then |
| 266 | in a Windows environment proxy settings are obtained from the registry's |
| 267 | Internet Settings section, and in a Mac OS X environment proxy information |
| 268 | is retrieved from the OS X System Configuration Framework. |
Senthil Kumaran | a51a1b3 | 2009-10-18 01:42:33 +0000 | [diff] [blame] | 269 | |
Christian Heimes | e25f35e | 2008-03-20 10:49:03 +0000 | [diff] [blame] | 270 | To disable autodetected proxy pass an empty dictionary. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 271 | |
| 272 | |
| 273 | .. class:: HTTPPasswordMgr() |
| 274 | |
| 275 | Keep a database of ``(realm, uri) -> (user, password)`` mappings. |
| 276 | |
| 277 | |
| 278 | .. class:: HTTPPasswordMgrWithDefaultRealm() |
| 279 | |
| 280 | Keep a database of ``(realm, uri) -> (user, password)`` mappings. A realm of |
| 281 | ``None`` is considered a catch-all realm, which is searched if no other realm |
| 282 | fits. |
| 283 | |
| 284 | |
R David Murray | 4c7f995 | 2015-04-16 16:36:18 -0400 | [diff] [blame] | 285 | .. class:: HTTPPasswordMgrWithPriorAuth() |
| 286 | |
| 287 | A variant of :class:`HTTPPasswordMgrWithDefaultRealm` that also has a |
| 288 | database of ``uri -> is_authenticated`` mappings. Can be used by a |
| 289 | BasicAuth handler to determine when to send authentication credentials |
| 290 | immediately instead of waiting for a ``401`` response first. |
| 291 | |
| 292 | .. versionadded:: 3.5 |
| 293 | |
| 294 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 295 | .. class:: AbstractBasicAuthHandler(password_mgr=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 296 | |
| 297 | This is a mixin class that helps with HTTP authentication, both to the remote |
| 298 | host and to a proxy. *password_mgr*, if given, should be something that is |
| 299 | compatible with :class:`HTTPPasswordMgr`; refer to section |
| 300 | :ref:`http-password-mgr` for information on the interface that must be |
R David Murray | 4c7f995 | 2015-04-16 16:36:18 -0400 | [diff] [blame] | 301 | supported. If *passwd_mgr* also provides ``is_authenticated`` and |
| 302 | ``update_authenticated`` methods (see |
| 303 | :ref:`http-password-mgr-with-prior-auth`), then the handler will use the |
| 304 | ``is_authenticated`` result for a given URI to determine whether or not to |
| 305 | send authentication credentials with the request. If ``is_authenticated`` |
Berker Peksag | 6d7dced | 2015-04-17 04:58:45 +0300 | [diff] [blame] | 306 | returns ``True`` for the URI, credentials are sent. If ``is_authenticated`` |
R David Murray | 4c7f995 | 2015-04-16 16:36:18 -0400 | [diff] [blame] | 307 | is ``False``, credentials are not sent, and then if a ``401`` response is |
| 308 | received the request is re-sent with the authentication credentials. If |
| 309 | authentication succeeds, ``update_authenticated`` is called to set |
| 310 | ``is_authenticated`` ``True`` for the URI, so that subsequent requests to |
| 311 | the URI or any of its super-URIs will automatically include the |
| 312 | authentication credentials. |
| 313 | |
Berker Peksag | 6d7dced | 2015-04-17 04:58:45 +0300 | [diff] [blame] | 314 | .. versionadded:: 3.5 |
| 315 | Added ``is_authenticated`` support. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 316 | |
| 317 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 318 | .. class:: HTTPBasicAuthHandler(password_mgr=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 319 | |
Senthil Kumaran | 4de00a2 | 2011-05-11 21:17:57 +0800 | [diff] [blame] | 320 | Handle authentication with the remote host. *password_mgr*, if given, should |
| 321 | be something that is compatible with :class:`HTTPPasswordMgr`; refer to |
| 322 | section :ref:`http-password-mgr` for information on the interface that must |
| 323 | be supported. HTTPBasicAuthHandler will raise a :exc:`ValueError` when |
| 324 | presented with a wrong Authentication scheme. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 325 | |
| 326 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 327 | .. class:: ProxyBasicAuthHandler(password_mgr=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 328 | |
| 329 | Handle authentication with the proxy. *password_mgr*, if given, should be |
| 330 | something that is compatible with :class:`HTTPPasswordMgr`; refer to section |
| 331 | :ref:`http-password-mgr` for information on the interface that must be |
| 332 | supported. |
| 333 | |
| 334 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 335 | .. class:: AbstractDigestAuthHandler(password_mgr=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 336 | |
| 337 | This is a mixin class that helps with HTTP authentication, both to the remote |
| 338 | host and to a proxy. *password_mgr*, if given, should be something that is |
| 339 | compatible with :class:`HTTPPasswordMgr`; refer to section |
| 340 | :ref:`http-password-mgr` for information on the interface that must be |
| 341 | supported. |
| 342 | |
| 343 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 344 | .. class:: HTTPDigestAuthHandler(password_mgr=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 345 | |
Senthil Kumaran | 4de00a2 | 2011-05-11 21:17:57 +0800 | [diff] [blame] | 346 | Handle authentication with the remote host. *password_mgr*, if given, should |
| 347 | be something that is compatible with :class:`HTTPPasswordMgr`; refer to |
| 348 | section :ref:`http-password-mgr` for information on the interface that must |
| 349 | be supported. When both Digest Authentication Handler and Basic |
| 350 | Authentication Handler are both added, Digest Authentication is always tried |
| 351 | first. If the Digest Authentication returns a 40x response again, it is sent |
| 352 | to Basic Authentication handler to Handle. This Handler method will raise a |
| 353 | :exc:`ValueError` when presented with an authentication scheme other than |
| 354 | Digest or Basic. |
| 355 | |
Ezio Melotti | e9c7d6c | 2011-05-12 01:10:57 +0300 | [diff] [blame] | 356 | .. versionchanged:: 3.3 |
| 357 | Raise :exc:`ValueError` on unsupported Authentication Scheme. |
Senthil Kumaran | 4de00a2 | 2011-05-11 21:17:57 +0800 | [diff] [blame] | 358 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 359 | |
| 360 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 361 | .. class:: ProxyDigestAuthHandler(password_mgr=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 362 | |
| 363 | Handle authentication with the proxy. *password_mgr*, if given, should be |
| 364 | something that is compatible with :class:`HTTPPasswordMgr`; refer to section |
| 365 | :ref:`http-password-mgr` for information on the interface that must be |
| 366 | supported. |
| 367 | |
| 368 | |
| 369 | .. class:: HTTPHandler() |
| 370 | |
| 371 | A class to handle opening of HTTP URLs. |
| 372 | |
| 373 | |
Antoine Pitrou | 803e6d6 | 2010-10-13 10:36:15 +0000 | [diff] [blame] | 374 | .. class:: HTTPSHandler(debuglevel=0, context=None, check_hostname=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 375 | |
Antoine Pitrou | 803e6d6 | 2010-10-13 10:36:15 +0000 | [diff] [blame] | 376 | A class to handle opening of HTTPS URLs. *context* and *check_hostname* |
| 377 | have the same meaning as in :class:`http.client.HTTPSConnection`. |
| 378 | |
| 379 | .. versionchanged:: 3.2 |
| 380 | *context* and *check_hostname* were added. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 381 | |
| 382 | |
| 383 | .. class:: FileHandler() |
| 384 | |
| 385 | Open local files. |
| 386 | |
Antoine Pitrou | df204be | 2012-11-24 17:59:08 +0100 | [diff] [blame] | 387 | .. class:: DataHandler() |
| 388 | |
| 389 | Open data URLs. |
| 390 | |
| 391 | .. versionadded:: 3.4 |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 392 | |
| 393 | .. class:: FTPHandler() |
| 394 | |
| 395 | Open FTP URLs. |
| 396 | |
| 397 | |
| 398 | .. class:: CacheFTPHandler() |
| 399 | |
| 400 | Open FTP URLs, keeping a cache of open FTP connections to minimize delays. |
| 401 | |
| 402 | |
| 403 | .. class:: UnknownHandler() |
| 404 | |
| 405 | A catch-all class to handle unknown URLs. |
| 406 | |
| 407 | |
Senthil Kumaran | ed270fa | 2011-07-18 06:42:46 +0800 | [diff] [blame] | 408 | .. class:: HTTPErrorProcessor() |
| 409 | |
| 410 | Process HTTP error responses. |
| 411 | |
| 412 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 413 | .. _request-objects: |
| 414 | |
| 415 | Request Objects |
| 416 | --------------- |
| 417 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 418 | The following methods describe :class:`Request`'s public interface, |
| 419 | and so all may be overridden in subclasses. It also defines several |
| 420 | public attributes that can be used by clients to inspect the parsed |
| 421 | request. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 422 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 423 | .. attribute:: Request.full_url |
| 424 | |
| 425 | The original URL passed to the constructor. |
| 426 | |
Senthil Kumaran | 8307075 | 2013-05-24 09:14:12 -0700 | [diff] [blame] | 427 | .. versionchanged:: 3.4 |
| 428 | |
| 429 | Request.full_url is a property with setter, getter and a deleter. Getting |
| 430 | :attr:`~Request.full_url` returns the original request URL with the |
| 431 | fragment, if it was present. |
| 432 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 433 | .. attribute:: Request.type |
| 434 | |
| 435 | The URI scheme. |
| 436 | |
| 437 | .. attribute:: Request.host |
| 438 | |
| 439 | The URI authority, typically a host, but may also contain a port |
| 440 | separated by a colon. |
| 441 | |
| 442 | .. attribute:: Request.origin_req_host |
| 443 | |
| 444 | The original host for the request, without port. |
| 445 | |
| 446 | .. attribute:: Request.selector |
| 447 | |
| 448 | The URI path. If the :class:`Request` uses a proxy, then selector |
| 449 | will be the full url that is passed to the proxy. |
| 450 | |
| 451 | .. attribute:: Request.data |
| 452 | |
| 453 | The entity body for the request, or None if not specified. |
| 454 | |
Andrew Svetlov | bff98fe | 2012-11-27 23:06:19 +0200 | [diff] [blame] | 455 | .. versionchanged:: 3.4 |
| 456 | Changing value of :attr:`Request.data` now deletes "Content-Length" |
| 457 | header if it was previously set or calculated. |
| 458 | |
Jeremy Hylton | e257316 | 2009-03-31 14:38:13 +0000 | [diff] [blame] | 459 | .. attribute:: Request.unverifiable |
| 460 | |
| 461 | boolean, indicates whether the request is unverifiable as defined |
| 462 | by RFC 2965. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 463 | |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 464 | .. attribute:: Request.method |
| 465 | |
Larry Hastings | 3732ed2 | 2014-03-15 21:13:56 -0700 | [diff] [blame] | 466 | The HTTP request method to use. By default its value is :const:`None`, |
| 467 | which means that :meth:`~Request.get_method` will do its normal computation |
| 468 | of the method to be used. Its value can be set (thus overriding the default |
| 469 | computation in :meth:`~Request.get_method`) either by providing a default |
| 470 | value by setting it at the class level in a :class:`Request` subclass, or by |
| 471 | passing a value in to the :class:`Request` constructor via the *method* |
| 472 | argument. |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 473 | |
Senthil Kumaran | a41c942 | 2011-10-20 02:37:08 +0800 | [diff] [blame] | 474 | .. versionadded:: 3.3 |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 475 | |
Larry Hastings | 3732ed2 | 2014-03-15 21:13:56 -0700 | [diff] [blame] | 476 | .. versionchanged:: 3.4 |
| 477 | A default value can now be set in subclasses; previously it could only |
| 478 | be set via the constructor argument. |
| 479 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 480 | |
| 481 | .. method:: Request.get_method() |
| 482 | |
Senthil Kumaran | de49d64 | 2011-10-16 23:54:44 +0800 | [diff] [blame] | 483 | Return a string indicating the HTTP request method. If |
| 484 | :attr:`Request.method` is not ``None``, return its value, otherwise return |
| 485 | ``'GET'`` if :attr:`Request.data` is ``None``, or ``'POST'`` if it's not. |
| 486 | This is only meaningful for HTTP requests. |
| 487 | |
Florent Xicluna | 95483b6 | 2011-10-19 11:44:51 +0200 | [diff] [blame] | 488 | .. versionchanged:: 3.3 |
Senthil Kumaran | a41c942 | 2011-10-20 02:37:08 +0800 | [diff] [blame] | 489 | get_method now looks at the value of :attr:`Request.method`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 490 | |
| 491 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 492 | .. method:: Request.add_header(key, val) |
| 493 | |
| 494 | Add another header to the request. Headers are currently ignored by all |
| 495 | handlers except HTTP handlers, where they are added to the list of headers sent |
| 496 | to the server. Note that there cannot be more than one header with the same |
| 497 | name, and later calls will overwrite previous calls in case the *key* collides. |
| 498 | Currently, this is no loss of HTTP functionality, since all headers which have |
| 499 | meaning when used more than once have a (header-specific) way of gaining the |
| 500 | same functionality using only one header. |
| 501 | |
| 502 | |
| 503 | .. method:: Request.add_unredirected_header(key, header) |
| 504 | |
| 505 | Add a header that will not be added to a redirected request. |
| 506 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 507 | |
| 508 | .. method:: Request.has_header(header) |
| 509 | |
| 510 | Return whether the instance has the named header (checks both regular and |
| 511 | unredirected). |
| 512 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 513 | |
Andrew Svetlov | bff98fe | 2012-11-27 23:06:19 +0200 | [diff] [blame] | 514 | .. method:: Request.remove_header(header) |
| 515 | |
| 516 | Remove named header from the request instance (both from regular and |
| 517 | unredirected headers). |
| 518 | |
Georg Brandl | c0fc958 | 2012-12-22 10:36:45 +0100 | [diff] [blame] | 519 | .. versionadded:: 3.4 |
| 520 | |
Andrew Svetlov | bff98fe | 2012-11-27 23:06:19 +0200 | [diff] [blame] | 521 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 522 | .. method:: Request.get_full_url() |
| 523 | |
| 524 | Return the URL given in the constructor. |
| 525 | |
Senthil Kumaran | 8307075 | 2013-05-24 09:14:12 -0700 | [diff] [blame] | 526 | .. versionchanged:: 3.4 |
| 527 | |
| 528 | Returns :attr:`Request.full_url` |
| 529 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 530 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 531 | .. method:: Request.set_proxy(host, type) |
| 532 | |
| 533 | Prepare the request by connecting to a proxy server. The *host* and *type* will |
| 534 | replace those of the instance, and the instance's selector will be the original |
| 535 | URL given in the constructor. |
| 536 | |
| 537 | |
Senthil Kumaran | 8dc5004 | 2012-04-29 11:50:39 +0800 | [diff] [blame] | 538 | .. method:: Request.get_header(header_name, default=None) |
| 539 | |
| 540 | Return the value of the given header. If the header is not present, return |
| 541 | the default value. |
| 542 | |
| 543 | |
| 544 | .. method:: Request.header_items() |
| 545 | |
| 546 | Return a list of tuples (header_name, header_value) of the Request headers. |
| 547 | |
Senthil Kumaran | 6ddec17 | 2013-03-19 18:03:39 -0700 | [diff] [blame] | 548 | .. versionchanged:: 3.4 |
Georg Brandl | df48b97 | 2014-03-24 09:06:18 +0100 | [diff] [blame] | 549 | The request methods add_data, has_data, get_data, get_type, get_host, |
| 550 | get_selector, get_origin_req_host and is_unverifiable that were deprecated |
| 551 | since 3.3 have been removed. |
| 552 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 553 | |
| 554 | .. _opener-director-objects: |
| 555 | |
| 556 | OpenerDirector Objects |
| 557 | ---------------------- |
| 558 | |
| 559 | :class:`OpenerDirector` instances have the following methods: |
| 560 | |
| 561 | |
| 562 | .. method:: OpenerDirector.add_handler(handler) |
| 563 | |
| 564 | *handler* should be an instance of :class:`BaseHandler`. The following methods |
| 565 | are searched, and added to the possible chains (note that HTTP errors are a |
| 566 | special case). |
| 567 | |
| 568 | * :meth:`protocol_open` --- signal that the handler knows how to open *protocol* |
| 569 | URLs. |
| 570 | |
| 571 | * :meth:`http_error_type` --- signal that the handler knows how to handle HTTP |
| 572 | errors with HTTP error code *type*. |
| 573 | |
| 574 | * :meth:`protocol_error` --- signal that the handler knows how to handle errors |
| 575 | from (non-\ ``http``) *protocol*. |
| 576 | |
| 577 | * :meth:`protocol_request` --- signal that the handler knows how to pre-process |
| 578 | *protocol* requests. |
| 579 | |
| 580 | * :meth:`protocol_response` --- signal that the handler knows how to |
| 581 | post-process *protocol* responses. |
| 582 | |
| 583 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 584 | .. method:: OpenerDirector.open(url, data=None[, timeout]) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 585 | |
| 586 | Open the given *url* (which can be a request object or a string), optionally |
Alexandre Vassalotti | 5f8ced2 | 2008-05-16 00:03:33 +0000 | [diff] [blame] | 587 | passing the given *data*. Arguments, return values and exceptions raised are |
| 588 | the same as those of :func:`urlopen` (which simply calls the :meth:`open` |
| 589 | method on the currently installed global :class:`OpenerDirector`). The |
| 590 | optional *timeout* parameter specifies a timeout in seconds for blocking |
Georg Brandl | f78e02b | 2008-06-10 17:40:04 +0000 | [diff] [blame] | 591 | operations like the connection attempt (if not specified, the global default |
Georg Brandl | 325524e | 2010-05-21 20:57:33 +0000 | [diff] [blame] | 592 | timeout setting will be used). The timeout feature actually works only for |
Senthil Kumaran | c08d907 | 2010-10-05 18:46:56 +0000 | [diff] [blame] | 593 | HTTP, HTTPS and FTP connections). |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 594 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 595 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 596 | .. method:: OpenerDirector.error(proto, *args) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 597 | |
| 598 | Handle an error of the given protocol. This will call the registered error |
| 599 | handlers for the given protocol with the given arguments (which are protocol |
| 600 | specific). The HTTP protocol is a special case which uses the HTTP response |
| 601 | code to determine the specific error handler; refer to the :meth:`http_error_\*` |
| 602 | methods of the handler classes. |
| 603 | |
| 604 | Return values and exceptions raised are the same as those of :func:`urlopen`. |
| 605 | |
| 606 | OpenerDirector objects open URLs in three stages: |
| 607 | |
| 608 | The order in which these methods are called within each stage is determined by |
| 609 | sorting the handler instances. |
| 610 | |
| 611 | #. Every handler with a method named like :meth:`protocol_request` has that |
| 612 | method called to pre-process the request. |
| 613 | |
| 614 | #. Handlers with a method named like :meth:`protocol_open` are called to handle |
| 615 | the request. This stage ends when a handler either returns a non-\ :const:`None` |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 616 | value (ie. a response), or raises an exception (usually |
| 617 | :exc:`~urllib.error.URLError`). Exceptions are allowed to propagate. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 618 | |
| 619 | In fact, the above algorithm is first tried for methods named |
| 620 | :meth:`default_open`. If all such methods return :const:`None`, the algorithm |
| 621 | is repeated for methods named like :meth:`protocol_open`. If all such methods |
| 622 | return :const:`None`, the algorithm is repeated for methods named |
| 623 | :meth:`unknown_open`. |
| 624 | |
| 625 | Note that the implementation of these methods may involve calls of the parent |
Georg Brandl | a5eacee | 2010-07-23 16:55:26 +0000 | [diff] [blame] | 626 | :class:`OpenerDirector` instance's :meth:`~OpenerDirector.open` and |
| 627 | :meth:`~OpenerDirector.error` methods. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 628 | |
| 629 | #. Every handler with a method named like :meth:`protocol_response` has that |
| 630 | method called to post-process the response. |
| 631 | |
| 632 | |
| 633 | .. _base-handler-objects: |
| 634 | |
| 635 | BaseHandler Objects |
| 636 | ------------------- |
| 637 | |
| 638 | :class:`BaseHandler` objects provide a couple of methods that are directly |
| 639 | useful, and others that are meant to be used by derived classes. These are |
| 640 | intended for direct use: |
| 641 | |
| 642 | |
| 643 | .. method:: BaseHandler.add_parent(director) |
| 644 | |
| 645 | Add a director as parent. |
| 646 | |
| 647 | |
| 648 | .. method:: BaseHandler.close() |
| 649 | |
| 650 | Remove any parents. |
| 651 | |
Senthil Kumaran | a6bac95 | 2011-07-04 11:28:30 -0700 | [diff] [blame] | 652 | The following attribute and methods should only be used by classes derived from |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 653 | :class:`BaseHandler`. |
| 654 | |
| 655 | .. note:: |
| 656 | |
| 657 | The convention has been adopted that subclasses defining |
| 658 | :meth:`protocol_request` or :meth:`protocol_response` methods are named |
| 659 | :class:`\*Processor`; all others are named :class:`\*Handler`. |
| 660 | |
| 661 | |
| 662 | .. attribute:: BaseHandler.parent |
| 663 | |
| 664 | A valid :class:`OpenerDirector`, which can be used to open using a different |
| 665 | protocol, or handle errors. |
| 666 | |
| 667 | |
| 668 | .. method:: BaseHandler.default_open(req) |
| 669 | |
| 670 | This method is *not* defined in :class:`BaseHandler`, but subclasses should |
| 671 | define it if they want to catch all URLs. |
| 672 | |
| 673 | This method, if implemented, will be called by the parent |
| 674 | :class:`OpenerDirector`. It should return a file-like object as described in |
| 675 | the return value of the :meth:`open` of :class:`OpenerDirector`, or ``None``. |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 676 | It should raise :exc:`~urllib.error.URLError`, unless a truly exceptional |
| 677 | thing happens (for example, :exc:`MemoryError` should not be mapped to |
| 678 | :exc:`URLError`). |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 679 | |
| 680 | This method will be called before any protocol-specific open method. |
| 681 | |
| 682 | |
| 683 | .. method:: BaseHandler.protocol_open(req) |
| 684 | :noindex: |
| 685 | |
| 686 | This method is *not* defined in :class:`BaseHandler`, but subclasses should |
| 687 | define it if they want to handle URLs with the given protocol. |
| 688 | |
| 689 | This method, if defined, will be called by the parent :class:`OpenerDirector`. |
| 690 | Return values should be the same as for :meth:`default_open`. |
| 691 | |
| 692 | |
| 693 | .. method:: BaseHandler.unknown_open(req) |
| 694 | |
| 695 | This method is *not* defined in :class:`BaseHandler`, but subclasses should |
| 696 | define it if they want to catch all URLs with no specific registered handler to |
| 697 | open it. |
| 698 | |
| 699 | This method, if implemented, will be called by the :attr:`parent` |
| 700 | :class:`OpenerDirector`. Return values should be the same as for |
| 701 | :meth:`default_open`. |
| 702 | |
| 703 | |
| 704 | .. method:: BaseHandler.http_error_default(req, fp, code, msg, hdrs) |
| 705 | |
| 706 | This method is *not* defined in :class:`BaseHandler`, but subclasses should |
| 707 | override it if they intend to provide a catch-all for otherwise unhandled HTTP |
| 708 | errors. It will be called automatically by the :class:`OpenerDirector` getting |
| 709 | the error, and should not normally be called in other circumstances. |
| 710 | |
| 711 | *req* will be a :class:`Request` object, *fp* will be a file-like object with |
| 712 | the HTTP error body, *code* will be the three-digit code of the error, *msg* |
| 713 | will be the user-visible explanation of the code and *hdrs* will be a mapping |
| 714 | object with the headers of the error. |
| 715 | |
| 716 | Return values and exceptions raised should be the same as those of |
| 717 | :func:`urlopen`. |
| 718 | |
| 719 | |
| 720 | .. method:: BaseHandler.http_error_nnn(req, fp, code, msg, hdrs) |
| 721 | |
| 722 | *nnn* should be a three-digit HTTP error code. This method is also not defined |
| 723 | in :class:`BaseHandler`, but will be called, if it exists, on an instance of a |
| 724 | subclass, when an HTTP error with code *nnn* occurs. |
| 725 | |
| 726 | Subclasses should override this method to handle specific HTTP errors. |
| 727 | |
| 728 | Arguments, return values and exceptions raised should be the same as for |
| 729 | :meth:`http_error_default`. |
| 730 | |
| 731 | |
| 732 | .. method:: BaseHandler.protocol_request(req) |
| 733 | :noindex: |
| 734 | |
| 735 | This method is *not* defined in :class:`BaseHandler`, but subclasses should |
| 736 | define it if they want to pre-process requests of the given protocol. |
| 737 | |
| 738 | This method, if defined, will be called by the parent :class:`OpenerDirector`. |
| 739 | *req* will be a :class:`Request` object. The return value should be a |
| 740 | :class:`Request` object. |
| 741 | |
| 742 | |
| 743 | .. method:: BaseHandler.protocol_response(req, response) |
| 744 | :noindex: |
| 745 | |
| 746 | This method is *not* defined in :class:`BaseHandler`, but subclasses should |
| 747 | define it if they want to post-process responses of the given protocol. |
| 748 | |
| 749 | This method, if defined, will be called by the parent :class:`OpenerDirector`. |
| 750 | *req* will be a :class:`Request` object. *response* will be an object |
| 751 | implementing the same interface as the return value of :func:`urlopen`. The |
| 752 | return value should implement the same interface as the return value of |
| 753 | :func:`urlopen`. |
| 754 | |
| 755 | |
| 756 | .. _http-redirect-handler: |
| 757 | |
| 758 | HTTPRedirectHandler Objects |
| 759 | --------------------------- |
| 760 | |
| 761 | .. note:: |
| 762 | |
| 763 | Some HTTP redirections require action from this module's client code. If this |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 764 | is the case, :exc:`~urllib.error.HTTPError` is raised. See :rfc:`2616` for |
| 765 | details of the precise meanings of the various redirection codes. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 766 | |
guido@google.com | a119df9 | 2011-03-29 11:41:02 -0700 | [diff] [blame] | 767 | An :class:`HTTPError` exception raised as a security consideration if the |
| 768 | HTTPRedirectHandler is presented with a redirected url which is not an HTTP, |
| 769 | HTTPS or FTP url. |
| 770 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 771 | |
Georg Brandl | 9617a59 | 2009-02-13 10:40:43 +0000 | [diff] [blame] | 772 | .. method:: HTTPRedirectHandler.redirect_request(req, fp, code, msg, hdrs, newurl) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 773 | |
| 774 | Return a :class:`Request` or ``None`` in response to a redirect. This is called |
| 775 | by the default implementations of the :meth:`http_error_30\*` methods when a |
| 776 | redirection is received from the server. If a redirection should take place, |
| 777 | return a new :class:`Request` to allow :meth:`http_error_30\*` to perform the |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 778 | redirect to *newurl*. Otherwise, raise :exc:`~urllib.error.HTTPError` if |
| 779 | no other handler should try to handle this URL, or return ``None`` if you |
| 780 | can't but another handler might. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 781 | |
| 782 | .. note:: |
| 783 | |
| 784 | The default implementation of this method does not strictly follow :rfc:`2616`, |
| 785 | which says that 301 and 302 responses to ``POST`` requests must not be |
| 786 | automatically redirected without confirmation by the user. In reality, browsers |
| 787 | do allow automatic redirection of these responses, changing the POST to a |
| 788 | ``GET``, and the default implementation reproduces this behavior. |
| 789 | |
| 790 | |
| 791 | .. method:: HTTPRedirectHandler.http_error_301(req, fp, code, msg, hdrs) |
| 792 | |
Georg Brandl | 9617a59 | 2009-02-13 10:40:43 +0000 | [diff] [blame] | 793 | Redirect to the ``Location:`` or ``URI:`` URL. This method is called by the |
| 794 | parent :class:`OpenerDirector` when getting an HTTP 'moved permanently' response. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 795 | |
| 796 | |
| 797 | .. method:: HTTPRedirectHandler.http_error_302(req, fp, code, msg, hdrs) |
| 798 | |
| 799 | The same as :meth:`http_error_301`, but called for the 'found' response. |
| 800 | |
| 801 | |
| 802 | .. method:: HTTPRedirectHandler.http_error_303(req, fp, code, msg, hdrs) |
| 803 | |
| 804 | The same as :meth:`http_error_301`, but called for the 'see other' response. |
| 805 | |
| 806 | |
| 807 | .. method:: HTTPRedirectHandler.http_error_307(req, fp, code, msg, hdrs) |
| 808 | |
| 809 | The same as :meth:`http_error_301`, but called for the 'temporary redirect' |
| 810 | response. |
| 811 | |
| 812 | |
| 813 | .. _http-cookie-processor: |
| 814 | |
| 815 | HTTPCookieProcessor Objects |
| 816 | --------------------------- |
| 817 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 818 | :class:`HTTPCookieProcessor` instances have one attribute: |
| 819 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 820 | .. attribute:: HTTPCookieProcessor.cookiejar |
| 821 | |
Georg Brandl | 2442015 | 2008-05-26 16:32:26 +0000 | [diff] [blame] | 822 | The :class:`http.cookiejar.CookieJar` in which cookies are stored. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 823 | |
| 824 | |
| 825 | .. _proxy-handler: |
| 826 | |
| 827 | ProxyHandler Objects |
| 828 | -------------------- |
| 829 | |
| 830 | |
| 831 | .. method:: ProxyHandler.protocol_open(request) |
| 832 | :noindex: |
| 833 | |
| 834 | The :class:`ProxyHandler` will have a method :meth:`protocol_open` for every |
| 835 | *protocol* which has a proxy in the *proxies* dictionary given in the |
| 836 | constructor. The method will modify requests to go through the proxy, by |
| 837 | calling ``request.set_proxy()``, and call the next handler in the chain to |
| 838 | actually execute the protocol. |
| 839 | |
| 840 | |
| 841 | .. _http-password-mgr: |
| 842 | |
| 843 | HTTPPasswordMgr Objects |
| 844 | ----------------------- |
| 845 | |
| 846 | These methods are available on :class:`HTTPPasswordMgr` and |
| 847 | :class:`HTTPPasswordMgrWithDefaultRealm` objects. |
| 848 | |
| 849 | |
| 850 | .. method:: HTTPPasswordMgr.add_password(realm, uri, user, passwd) |
| 851 | |
| 852 | *uri* can be either a single URI, or a sequence of URIs. *realm*, *user* and |
| 853 | *passwd* must be strings. This causes ``(user, passwd)`` to be used as |
| 854 | authentication tokens when authentication for *realm* and a super-URI of any of |
| 855 | the given URIs is given. |
| 856 | |
| 857 | |
| 858 | .. method:: HTTPPasswordMgr.find_user_password(realm, authuri) |
| 859 | |
| 860 | Get user/password for given realm and URI, if any. This method will return |
| 861 | ``(None, None)`` if there is no matching user/password. |
| 862 | |
| 863 | For :class:`HTTPPasswordMgrWithDefaultRealm` objects, the realm ``None`` will be |
| 864 | searched if the given *realm* has no matching user/password. |
| 865 | |
| 866 | |
R David Murray | 4c7f995 | 2015-04-16 16:36:18 -0400 | [diff] [blame] | 867 | .. _http-password-mgr-with-prior-auth: |
| 868 | |
| 869 | HTTPPasswordMgrWithPriorAuth Objects |
| 870 | ------------------------------------ |
| 871 | |
| 872 | This password manager extends :class:`HTTPPasswordMgrWithDefaultRealm` to support |
| 873 | tracking URIs for which authentication credentials should always be sent. |
| 874 | |
| 875 | |
| 876 | .. method:: HTTPPasswordMgrWithPriorAuth.add_password(realm, uri, user, \ |
| 877 | passwd, is_authenticated=False) |
| 878 | |
| 879 | *realm*, *uri*, *user*, *passwd* are as for |
| 880 | :meth:`HTTPPasswordMgr.add_password`. *is_authenticated* sets the initial |
| 881 | value of the ``is_authenticated`` flag for the given URI or list of URIs. |
| 882 | If *is_authenticated* is specified as ``True``, *realm* is ignored. |
| 883 | |
| 884 | |
| 885 | .. method:: HTTPPasswordMgr.find_user_password(realm, authuri) |
| 886 | |
| 887 | Same as for :class:`HTTPPasswordMgrWithDefaultRealm` objects |
| 888 | |
| 889 | |
| 890 | .. method:: HTTPPasswordMgrWithPriorAuth.update_authenticated(self, uri, \ |
| 891 | is_authenticated=False) |
| 892 | |
| 893 | Update the ``is_authenticated`` flag for the given *uri* or list |
| 894 | of URIs. |
| 895 | |
| 896 | |
| 897 | .. method:: HTTPPasswordMgrWithPriorAuth.is_authenticated(self, authuri) |
| 898 | |
| 899 | Returns the current state of the ``is_authenticated`` flag for |
| 900 | the given URI. |
| 901 | |
| 902 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 903 | .. _abstract-basic-auth-handler: |
| 904 | |
| 905 | AbstractBasicAuthHandler Objects |
| 906 | -------------------------------- |
| 907 | |
| 908 | |
| 909 | .. method:: AbstractBasicAuthHandler.http_error_auth_reqed(authreq, host, req, headers) |
| 910 | |
| 911 | Handle an authentication request by getting a user/password pair, and re-trying |
| 912 | the request. *authreq* should be the name of the header where the information |
| 913 | about the realm is included in the request, *host* specifies the URL and path to |
| 914 | authenticate for, *req* should be the (failed) :class:`Request` object, and |
| 915 | *headers* should be the error headers. |
| 916 | |
| 917 | *host* is either an authority (e.g. ``"python.org"``) or a URL containing an |
| 918 | authority component (e.g. ``"http://python.org/"``). In either case, the |
| 919 | authority must not contain a userinfo component (so, ``"python.org"`` and |
| 920 | ``"python.org:80"`` are fine, ``"joe:password@python.org"`` is not). |
| 921 | |
| 922 | |
| 923 | .. _http-basic-auth-handler: |
| 924 | |
| 925 | HTTPBasicAuthHandler Objects |
| 926 | ---------------------------- |
| 927 | |
| 928 | |
| 929 | .. method:: HTTPBasicAuthHandler.http_error_401(req, fp, code, msg, hdrs) |
| 930 | |
| 931 | Retry the request with authentication information, if available. |
| 932 | |
| 933 | |
| 934 | .. _proxy-basic-auth-handler: |
| 935 | |
| 936 | ProxyBasicAuthHandler Objects |
| 937 | ----------------------------- |
| 938 | |
| 939 | |
| 940 | .. method:: ProxyBasicAuthHandler.http_error_407(req, fp, code, msg, hdrs) |
| 941 | |
| 942 | Retry the request with authentication information, if available. |
| 943 | |
| 944 | |
| 945 | .. _abstract-digest-auth-handler: |
| 946 | |
| 947 | AbstractDigestAuthHandler Objects |
| 948 | --------------------------------- |
| 949 | |
| 950 | |
| 951 | .. method:: AbstractDigestAuthHandler.http_error_auth_reqed(authreq, host, req, headers) |
| 952 | |
| 953 | *authreq* should be the name of the header where the information about the realm |
| 954 | is included in the request, *host* should be the host to authenticate to, *req* |
| 955 | should be the (failed) :class:`Request` object, and *headers* should be the |
| 956 | error headers. |
| 957 | |
| 958 | |
| 959 | .. _http-digest-auth-handler: |
| 960 | |
| 961 | HTTPDigestAuthHandler Objects |
| 962 | ----------------------------- |
| 963 | |
| 964 | |
| 965 | .. method:: HTTPDigestAuthHandler.http_error_401(req, fp, code, msg, hdrs) |
| 966 | |
| 967 | Retry the request with authentication information, if available. |
| 968 | |
| 969 | |
| 970 | .. _proxy-digest-auth-handler: |
| 971 | |
| 972 | ProxyDigestAuthHandler Objects |
| 973 | ------------------------------ |
| 974 | |
| 975 | |
| 976 | .. method:: ProxyDigestAuthHandler.http_error_407(req, fp, code, msg, hdrs) |
| 977 | |
| 978 | Retry the request with authentication information, if available. |
| 979 | |
| 980 | |
| 981 | .. _http-handler-objects: |
| 982 | |
| 983 | HTTPHandler Objects |
| 984 | ------------------- |
| 985 | |
| 986 | |
| 987 | .. method:: HTTPHandler.http_open(req) |
| 988 | |
| 989 | Send an HTTP request, which can be either GET or POST, depending on |
| 990 | ``req.has_data()``. |
| 991 | |
| 992 | |
| 993 | .. _https-handler-objects: |
| 994 | |
| 995 | HTTPSHandler Objects |
| 996 | -------------------- |
| 997 | |
| 998 | |
| 999 | .. method:: HTTPSHandler.https_open(req) |
| 1000 | |
| 1001 | Send an HTTPS request, which can be either GET or POST, depending on |
| 1002 | ``req.has_data()``. |
| 1003 | |
| 1004 | |
| 1005 | .. _file-handler-objects: |
| 1006 | |
| 1007 | FileHandler Objects |
| 1008 | ------------------- |
| 1009 | |
| 1010 | |
| 1011 | .. method:: FileHandler.file_open(req) |
| 1012 | |
| 1013 | Open the file locally, if there is no host name, or the host name is |
Senthil Kumaran | 383c32d | 2010-10-14 11:57:35 +0000 | [diff] [blame] | 1014 | ``'localhost'``. |
| 1015 | |
Georg Brandl | 61063cc | 2012-06-24 22:48:30 +0200 | [diff] [blame] | 1016 | .. versionchanged:: 3.2 |
| 1017 | This method is applicable only for local hostnames. When a remote |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 1018 | hostname is given, an :exc:`~urllib.error.URLError` is raised. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1019 | |
| 1020 | |
Antoine Pitrou | df204be | 2012-11-24 17:59:08 +0100 | [diff] [blame] | 1021 | .. _data-handler-objects: |
| 1022 | |
| 1023 | DataHandler Objects |
| 1024 | ------------------- |
| 1025 | |
| 1026 | .. method:: DataHandler.data_open(req) |
| 1027 | |
| 1028 | Read a data URL. This kind of URL contains the content encoded in the URL |
| 1029 | itself. The data URL syntax is specified in :rfc:`2397`. This implementation |
| 1030 | ignores white spaces in base64 encoded data URLs so the URL may be wrapped |
| 1031 | in whatever source file it comes from. But even though some browsers don't |
| 1032 | mind about a missing padding at the end of a base64 encoded data URL, this |
| 1033 | implementation will raise an :exc:`ValueError` in that case. |
| 1034 | |
| 1035 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1036 | .. _ftp-handler-objects: |
| 1037 | |
| 1038 | FTPHandler Objects |
| 1039 | ------------------ |
| 1040 | |
| 1041 | |
| 1042 | .. method:: FTPHandler.ftp_open(req) |
| 1043 | |
| 1044 | Open the FTP file indicated by *req*. The login is always done with empty |
| 1045 | username and password. |
| 1046 | |
| 1047 | |
| 1048 | .. _cacheftp-handler-objects: |
| 1049 | |
| 1050 | CacheFTPHandler Objects |
| 1051 | ----------------------- |
| 1052 | |
| 1053 | :class:`CacheFTPHandler` objects are :class:`FTPHandler` objects with the |
| 1054 | following additional methods: |
| 1055 | |
| 1056 | |
| 1057 | .. method:: CacheFTPHandler.setTimeout(t) |
| 1058 | |
| 1059 | Set timeout of connections to *t* seconds. |
| 1060 | |
| 1061 | |
| 1062 | .. method:: CacheFTPHandler.setMaxConns(m) |
| 1063 | |
| 1064 | Set maximum number of cached connections to *m*. |
| 1065 | |
| 1066 | |
| 1067 | .. _unknown-handler-objects: |
| 1068 | |
| 1069 | UnknownHandler Objects |
| 1070 | ---------------------- |
| 1071 | |
| 1072 | |
| 1073 | .. method:: UnknownHandler.unknown_open() |
| 1074 | |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 1075 | Raise a :exc:`~urllib.error.URLError` exception. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1076 | |
| 1077 | |
| 1078 | .. _http-error-processor-objects: |
| 1079 | |
| 1080 | HTTPErrorProcessor Objects |
| 1081 | -------------------------- |
| 1082 | |
Senthil Kumaran | 0215d09 | 2011-07-18 07:12:40 +0800 | [diff] [blame] | 1083 | .. method:: HTTPErrorProcessor.http_response() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1084 | |
| 1085 | Process HTTP error responses. |
| 1086 | |
| 1087 | For 200 error codes, the response object is returned immediately. |
| 1088 | |
| 1089 | For non-200 error codes, this simply passes the job on to the |
| 1090 | :meth:`protocol_error_code` handler methods, via :meth:`OpenerDirector.error`. |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 1091 | Eventually, :class:`HTTPDefaultErrorHandler` will raise an |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 1092 | :exc:`~urllib.error.HTTPError` if no other handler handles the error. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1093 | |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 1094 | |
Senthil Kumaran | 0215d09 | 2011-07-18 07:12:40 +0800 | [diff] [blame] | 1095 | .. method:: HTTPErrorProcessor.https_response() |
| 1096 | |
Senthil Kumaran | 3e7f33f | 2011-07-18 07:17:20 +0800 | [diff] [blame] | 1097 | Process HTTPS error responses. |
| 1098 | |
Senthil Kumaran | 0215d09 | 2011-07-18 07:12:40 +0800 | [diff] [blame] | 1099 | The behavior is same as :meth:`http_response`. |
| 1100 | |
| 1101 | |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 1102 | .. _urllib-request-examples: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1103 | |
| 1104 | Examples |
| 1105 | -------- |
| 1106 | |
Senthil Kumaran | 0c2d8b8 | 2010-04-22 10:53:30 +0000 | [diff] [blame] | 1107 | This example gets the python.org main page and displays the first 300 bytes of |
Georg Brandl | bdc55ab | 2010-04-20 18:15:54 +0000 | [diff] [blame] | 1108 | it. :: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1109 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1110 | >>> import urllib.request |
Berker Peksag | 9575e18 | 2015-04-12 13:52:49 +0300 | [diff] [blame] | 1111 | >>> with urllib.request.urlopen('http://www.python.org/') as f: |
| 1112 | ... print(f.read(300)) |
| 1113 | ... |
Senthil Kumaran | 0c2d8b8 | 2010-04-22 10:53:30 +0000 | [diff] [blame] | 1114 | b'<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" |
| 1115 | "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">\n\n\n<html |
| 1116 | xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">\n\n<head>\n |
| 1117 | <meta http-equiv="content-type" content="text/html; charset=utf-8" />\n |
| 1118 | <title>Python Programming ' |
Senthil Kumaran | b213ee3 | 2010-04-15 17:18:22 +0000 | [diff] [blame] | 1119 | |
Senthil Kumaran | 0c2d8b8 | 2010-04-22 10:53:30 +0000 | [diff] [blame] | 1120 | Note that urlopen returns a bytes object. This is because there is no way |
| 1121 | for urlopen to automatically determine the encoding of the byte stream |
| 1122 | it receives from the http server. In general, a program will decode |
| 1123 | the returned bytes object to string once it determines or guesses |
| 1124 | the appropriate encoding. |
Senthil Kumaran | b213ee3 | 2010-04-15 17:18:22 +0000 | [diff] [blame] | 1125 | |
Serhiy Storchaka | a4d170d | 2013-12-23 18:20:51 +0200 | [diff] [blame] | 1126 | The following W3C document, http://www.w3.org/International/O-charset\ , lists |
Senthil Kumaran | 0c2d8b8 | 2010-04-22 10:53:30 +0000 | [diff] [blame] | 1127 | the various ways in which a (X)HTML or a XML document could have specified its |
| 1128 | encoding information. |
| 1129 | |
Donald Stufft | 8b852f1 | 2014-05-20 12:58:38 -0400 | [diff] [blame] | 1130 | As the python.org website uses *utf-8* encoding as specified in its meta tag, we |
Senthil Kumaran | 21c71ba | 2012-03-13 19:47:51 -0700 | [diff] [blame] | 1131 | will use the same for decoding the bytes object. :: |
| 1132 | |
| 1133 | >>> with urllib.request.urlopen('http://www.python.org/') as f: |
| 1134 | ... print(f.read(100).decode('utf-8')) |
| 1135 | ... |
| 1136 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" |
| 1137 | "http://www.w3.org/TR/xhtml1/DTD/xhtm |
| 1138 | |
| 1139 | It is also possible to achieve the same result without using the |
| 1140 | :term:`context manager` approach. :: |
Senthil Kumaran | b213ee3 | 2010-04-15 17:18:22 +0000 | [diff] [blame] | 1141 | |
| 1142 | >>> import urllib.request |
| 1143 | >>> f = urllib.request.urlopen('http://www.python.org/') |
Georg Brandl | fe4fd83 | 2010-05-21 21:01:32 +0000 | [diff] [blame] | 1144 | >>> print(f.read(100).decode('utf-8')) |
Senthil Kumaran | 0c2d8b8 | 2010-04-22 10:53:30 +0000 | [diff] [blame] | 1145 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" |
| 1146 | "http://www.w3.org/TR/xhtml1/DTD/xhtm |
| 1147 | |
Senthil Kumaran | b213ee3 | 2010-04-15 17:18:22 +0000 | [diff] [blame] | 1148 | In the following example, we are sending a data-stream to the stdin of a CGI |
| 1149 | and reading the data it returns to us. Note that this example will only work |
| 1150 | when the Python installation supports SSL. :: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1151 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1152 | >>> import urllib.request |
| 1153 | >>> req = urllib.request.Request(url='https://localhost/cgi-bin/test.cgi', |
Senthil Kumaran | 2933312 | 2011-02-11 11:25:47 +0000 | [diff] [blame] | 1154 | ... data=b'This data is passed to stdin of the CGI') |
Berker Peksag | 9575e18 | 2015-04-12 13:52:49 +0300 | [diff] [blame] | 1155 | >>> with urllib.request.urlopen(req) as f: |
| 1156 | ... print(f.read().decode('utf-8')) |
| 1157 | ... |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1158 | Got Data: "This data is passed to stdin of the CGI" |
| 1159 | |
| 1160 | The code for the sample CGI used in the above example is:: |
| 1161 | |
| 1162 | #!/usr/bin/env python |
| 1163 | import sys |
| 1164 | data = sys.stdin.read() |
Martin Panter | ac34e09 | 2015-11-14 00:58:32 +0000 | [diff] [blame] | 1165 | print('Content-type: text/plain\n\nGot Data: "%s"' % data) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1166 | |
Senthil Kumaran | e66cc81 | 2013-03-13 13:42:47 -0700 | [diff] [blame] | 1167 | Here is an example of doing a ``PUT`` request using :class:`Request`:: |
| 1168 | |
| 1169 | import urllib.request |
| 1170 | DATA=b'some data' |
| 1171 | req = urllib.request.Request(url='http://localhost:8080', data=DATA,method='PUT') |
Berker Peksag | 9575e18 | 2015-04-12 13:52:49 +0300 | [diff] [blame] | 1172 | with urllib.request.urlopen(req) as f: |
| 1173 | pass |
Senthil Kumaran | e66cc81 | 2013-03-13 13:42:47 -0700 | [diff] [blame] | 1174 | print(f.status) |
| 1175 | print(f.reason) |
| 1176 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1177 | Use of Basic HTTP Authentication:: |
| 1178 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1179 | import urllib.request |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1180 | # Create an OpenerDirector with support for Basic HTTP Authentication... |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1181 | auth_handler = urllib.request.HTTPBasicAuthHandler() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1182 | auth_handler.add_password(realm='PDQ Application', |
| 1183 | uri='https://mahler:8092/site-updates.py', |
| 1184 | user='klem', |
| 1185 | passwd='kadidd!ehopper') |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1186 | opener = urllib.request.build_opener(auth_handler) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1187 | # ...and install it globally so it can be used with urlopen. |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1188 | urllib.request.install_opener(opener) |
| 1189 | urllib.request.urlopen('http://www.example.com/login.html') |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1190 | |
| 1191 | :func:`build_opener` provides many handlers by default, including a |
| 1192 | :class:`ProxyHandler`. By default, :class:`ProxyHandler` uses the environment |
| 1193 | variables named ``<scheme>_proxy``, where ``<scheme>`` is the URL scheme |
| 1194 | involved. For example, the :envvar:`http_proxy` environment variable is read to |
| 1195 | obtain the HTTP proxy's URL. |
| 1196 | |
| 1197 | This example replaces the default :class:`ProxyHandler` with one that uses |
Georg Brandl | 2ee470f | 2008-07-16 12:55:28 +0000 | [diff] [blame] | 1198 | programmatically-supplied proxy URLs, and adds proxy authorization support with |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1199 | :class:`ProxyBasicAuthHandler`. :: |
| 1200 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1201 | proxy_handler = urllib.request.ProxyHandler({'http': 'http://www.example.com:3128/'}) |
Senthil Kumaran | 037f836 | 2009-12-24 02:24:37 +0000 | [diff] [blame] | 1202 | proxy_auth_handler = urllib.request.ProxyBasicAuthHandler() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1203 | proxy_auth_handler.add_password('realm', 'host', 'username', 'password') |
| 1204 | |
Senthil Kumaran | 037f836 | 2009-12-24 02:24:37 +0000 | [diff] [blame] | 1205 | opener = urllib.request.build_opener(proxy_handler, proxy_auth_handler) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1206 | # This time, rather than install the OpenerDirector, we use it directly: |
| 1207 | opener.open('http://www.example.com/login.html') |
| 1208 | |
| 1209 | Adding HTTP headers: |
| 1210 | |
| 1211 | Use the *headers* argument to the :class:`Request` constructor, or:: |
| 1212 | |
Georg Brandl | 029986a | 2008-06-23 11:44:14 +0000 | [diff] [blame] | 1213 | import urllib.request |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1214 | req = urllib.request.Request('http://www.example.com/') |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1215 | req.add_header('Referer', 'http://www.python.org/') |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1216 | r = urllib.request.urlopen(req) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1217 | |
| 1218 | :class:`OpenerDirector` automatically adds a :mailheader:`User-Agent` header to |
| 1219 | every :class:`Request`. To change this:: |
| 1220 | |
Georg Brandl | 029986a | 2008-06-23 11:44:14 +0000 | [diff] [blame] | 1221 | import urllib.request |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1222 | opener = urllib.request.build_opener() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1223 | opener.addheaders = [('User-agent', 'Mozilla/5.0')] |
| 1224 | opener.open('http://www.example.com/') |
| 1225 | |
| 1226 | Also, remember that a few standard headers (:mailheader:`Content-Length`, |
Martin Panter | cda85a0 | 2015-11-24 22:33:18 +0000 | [diff] [blame] | 1227 | :mailheader:`Content-Type` and :mailheader:`Host`) |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 1228 | are added when the :class:`Request` is passed to :func:`urlopen` (or |
| 1229 | :meth:`OpenerDirector.open`). |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1230 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1231 | .. _urllib-examples: |
| 1232 | |
| 1233 | Here is an example session that uses the ``GET`` method to retrieve a URL |
| 1234 | containing parameters:: |
| 1235 | |
| 1236 | >>> import urllib.request |
| 1237 | >>> import urllib.parse |
| 1238 | >>> params = urllib.parse.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0}) |
Berker Peksag | 9575e18 | 2015-04-12 13:52:49 +0300 | [diff] [blame] | 1239 | >>> url = "http://www.musi-cal.com/cgi-bin/query?%s" % params |
| 1240 | >>> with urllib.request.urlopen(url) as f: |
| 1241 | ... print(f.read().decode('utf-8')) |
| 1242 | ... |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1243 | |
Senthil Kumaran | 2933312 | 2011-02-11 11:25:47 +0000 | [diff] [blame] | 1244 | The following example uses the ``POST`` method instead. Note that params output |
| 1245 | from urlencode is encoded to bytes before it is sent to urlopen as data:: |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1246 | |
| 1247 | >>> import urllib.request |
| 1248 | >>> import urllib.parse |
Senthil Kumaran | 6b3434a | 2012-03-15 18:11:16 -0700 | [diff] [blame] | 1249 | >>> data = urllib.parse.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0}) |
Martin Panter | cda85a0 | 2015-11-24 22:33:18 +0000 | [diff] [blame] | 1250 | >>> data = data.encode('ascii') |
| 1251 | >>> with urllib.request.urlopen("http://requestb.in/xrbl82xr", data) as f: |
Berker Peksag | 9575e18 | 2015-04-12 13:52:49 +0300 | [diff] [blame] | 1252 | ... print(f.read().decode('utf-8')) |
| 1253 | ... |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1254 | |
| 1255 | The following example uses an explicitly specified HTTP proxy, overriding |
| 1256 | environment settings:: |
| 1257 | |
| 1258 | >>> import urllib.request |
| 1259 | >>> proxies = {'http': 'http://proxy.example.com:8080/'} |
| 1260 | >>> opener = urllib.request.FancyURLopener(proxies) |
Berker Peksag | 9575e18 | 2015-04-12 13:52:49 +0300 | [diff] [blame] | 1261 | >>> with opener.open("http://www.python.org") as f: |
| 1262 | ... f.read().decode('utf-8') |
| 1263 | ... |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1264 | |
| 1265 | The following example uses no proxies at all, overriding environment settings:: |
| 1266 | |
| 1267 | >>> import urllib.request |
| 1268 | >>> opener = urllib.request.FancyURLopener({}) |
Berker Peksag | 9575e18 | 2015-04-12 13:52:49 +0300 | [diff] [blame] | 1269 | >>> with opener.open("http://www.python.org/") as f: |
| 1270 | ... f.read().decode('utf-8') |
| 1271 | ... |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1272 | |
| 1273 | |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1274 | Legacy interface |
| 1275 | ---------------- |
| 1276 | |
| 1277 | The following functions and classes are ported from the Python 2 module |
| 1278 | ``urllib`` (as opposed to ``urllib2``). They might become deprecated at |
| 1279 | some point in the future. |
| 1280 | |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1281 | .. function:: urlretrieve(url, filename=None, reporthook=None, data=None) |
| 1282 | |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1283 | Copy a network object denoted by a URL to a local file. If the URL |
| 1284 | points to a local file, the object will not be copied unless filename is supplied. |
| 1285 | Return a tuple ``(filename, headers)`` where *filename* is the |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1286 | local file name under which the object can be found, and *headers* is whatever |
| 1287 | the :meth:`info` method of the object returned by :func:`urlopen` returned (for |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1288 | a remote object). Exceptions are the same as for :func:`urlopen`. |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1289 | |
| 1290 | The second argument, if present, specifies the file location to copy to (if |
| 1291 | absent, the location will be a tempfile with a generated name). The third |
| 1292 | argument, if present, is a hook function that will be called once on |
| 1293 | establishment of the network connection and once after each block read |
| 1294 | thereafter. The hook will be passed three arguments; a count of blocks |
| 1295 | transferred so far, a block size in bytes, and the total size of the file. The |
| 1296 | third argument may be ``-1`` on older FTP servers which do not return a file |
| 1297 | size in response to a retrieval request. |
| 1298 | |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1299 | The following example illustrates the most common usage scenario:: |
| 1300 | |
| 1301 | >>> import urllib.request |
| 1302 | >>> local_filename, headers = urllib.request.urlretrieve('http://python.org/') |
| 1303 | >>> html = open(local_filename) |
| 1304 | >>> html.close() |
| 1305 | |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1306 | If the *url* uses the :file:`http:` scheme identifier, the optional *data* |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1307 | argument may be given to specify a ``POST`` request (normally the request |
Senthil Kumaran | 87684e6 | 2012-03-14 18:08:13 -0700 | [diff] [blame] | 1308 | type is ``GET``). The *data* argument must be a bytes object in standard |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1309 | :mimetype:`application/x-www-form-urlencoded` format; see the |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 1310 | :func:`urllib.parse.urlencode` function. |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1311 | |
| 1312 | :func:`urlretrieve` will raise :exc:`ContentTooShortError` when it detects that |
| 1313 | the amount of data available was less than the expected amount (which is the |
| 1314 | size reported by a *Content-Length* header). This can occur, for example, when |
| 1315 | the download is interrupted. |
| 1316 | |
| 1317 | The *Content-Length* is treated as a lower bound: if there's more data to read, |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1318 | urlretrieve reads more data, but if less data is available, it raises the |
| 1319 | exception. |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1320 | |
| 1321 | You can still retrieve the downloaded data in this case, it is stored in the |
| 1322 | :attr:`content` attribute of the exception instance. |
| 1323 | |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1324 | If no *Content-Length* header was supplied, urlretrieve can not check the size |
| 1325 | of the data it has downloaded, and just returns it. In this case you just have |
| 1326 | to assume that the download was successful. |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1327 | |
| 1328 | .. function:: urlcleanup() |
| 1329 | |
Senthil Kumaran | e24f96a | 2012-03-13 19:29:33 -0700 | [diff] [blame] | 1330 | Cleans up temporary files that may have been left behind by previous |
| 1331 | calls to :func:`urlretrieve`. |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1332 | |
| 1333 | .. class:: URLopener(proxies=None, **x509) |
| 1334 | |
Senthil Kumaran | 6227c69 | 2013-03-18 17:09:50 -0700 | [diff] [blame] | 1335 | .. deprecated:: 3.3 |
| 1336 | |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1337 | Base class for opening and reading URLs. Unless you need to support opening |
| 1338 | objects using schemes other than :file:`http:`, :file:`ftp:`, or :file:`file:`, |
| 1339 | you probably want to use :class:`FancyURLopener`. |
| 1340 | |
| 1341 | By default, the :class:`URLopener` class sends a :mailheader:`User-Agent` header |
| 1342 | of ``urllib/VVV``, where *VVV* is the :mod:`urllib` version number. |
| 1343 | Applications can define their own :mailheader:`User-Agent` header by subclassing |
| 1344 | :class:`URLopener` or :class:`FancyURLopener` and setting the class attribute |
| 1345 | :attr:`version` to an appropriate string value in the subclass definition. |
| 1346 | |
| 1347 | The optional *proxies* parameter should be a dictionary mapping scheme names to |
| 1348 | proxy URLs, where an empty dictionary turns proxies off completely. Its default |
| 1349 | value is ``None``, in which case environmental proxy settings will be used if |
| 1350 | present, as discussed in the definition of :func:`urlopen`, above. |
| 1351 | |
| 1352 | Additional keyword parameters, collected in *x509*, may be used for |
| 1353 | authentication of the client when using the :file:`https:` scheme. The keywords |
| 1354 | *key_file* and *cert_file* are supported to provide an SSL key and certificate; |
| 1355 | both are needed to support client authentication. |
| 1356 | |
Antoine Pitrou | 4272d6a | 2011-10-12 19:10:10 +0200 | [diff] [blame] | 1357 | :class:`URLopener` objects will raise an :exc:`OSError` exception if the server |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1358 | returns an error code. |
| 1359 | |
| 1360 | .. method:: open(fullurl, data=None) |
| 1361 | |
| 1362 | Open *fullurl* using the appropriate protocol. This method sets up cache and |
| 1363 | proxy information, then calls the appropriate open method with its input |
| 1364 | arguments. If the scheme is not recognized, :meth:`open_unknown` is called. |
| 1365 | The *data* argument has the same meaning as the *data* argument of |
| 1366 | :func:`urlopen`. |
| 1367 | |
| 1368 | |
| 1369 | .. method:: open_unknown(fullurl, data=None) |
| 1370 | |
| 1371 | Overridable interface to open unknown URL types. |
| 1372 | |
| 1373 | |
| 1374 | .. method:: retrieve(url, filename=None, reporthook=None, data=None) |
| 1375 | |
| 1376 | Retrieves the contents of *url* and places it in *filename*. The return value |
Serhiy Storchaka | d65c949 | 2015-11-02 14:10:23 +0200 | [diff] [blame] | 1377 | is a tuple consisting of a local filename and either an |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1378 | :class:`email.message.Message` object containing the response headers (for remote |
| 1379 | URLs) or ``None`` (for local URLs). The caller must then open and read the |
| 1380 | contents of *filename*. If *filename* is not given and the URL refers to a |
| 1381 | local file, the input filename is returned. If the URL is non-local and |
| 1382 | *filename* is not given, the filename is the output of :func:`tempfile.mktemp` |
| 1383 | with a suffix that matches the suffix of the last path component of the input |
| 1384 | URL. If *reporthook* is given, it must be a function accepting three numeric |
Gregory P. Smith | 6b0bdab | 2012-11-10 13:43:44 -0800 | [diff] [blame] | 1385 | parameters: A chunk number, the maximum size chunks are read in and the total size of the download |
| 1386 | (-1 if unknown). It will be called once at the start and after each chunk of data is read from the |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1387 | network. *reporthook* is ignored for local URLs. |
| 1388 | |
| 1389 | If the *url* uses the :file:`http:` scheme identifier, the optional *data* |
| 1390 | argument may be given to specify a ``POST`` request (normally the request type |
| 1391 | is ``GET``). The *data* argument must in standard |
Serhiy Storchaka | 5e1c053 | 2013-10-13 20:06:50 +0300 | [diff] [blame] | 1392 | :mimetype:`application/x-www-form-urlencoded` format; see the |
| 1393 | :func:`urllib.parse.urlencode` function. |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1394 | |
| 1395 | |
| 1396 | .. attribute:: version |
| 1397 | |
| 1398 | Variable that specifies the user agent of the opener object. To get |
| 1399 | :mod:`urllib` to tell servers that it is a particular user agent, set this in a |
| 1400 | subclass as a class variable or in the constructor before calling the base |
| 1401 | constructor. |
| 1402 | |
| 1403 | |
| 1404 | .. class:: FancyURLopener(...) |
| 1405 | |
Senthil Kumaran | 6227c69 | 2013-03-18 17:09:50 -0700 | [diff] [blame] | 1406 | .. deprecated:: 3.3 |
| 1407 | |
Antoine Pitrou | b8eb9cb | 2010-12-15 19:07:26 +0000 | [diff] [blame] | 1408 | :class:`FancyURLopener` subclasses :class:`URLopener` providing default handling |
| 1409 | for the following HTTP response codes: 301, 302, 303, 307 and 401. For the 30x |
| 1410 | response codes listed above, the :mailheader:`Location` header is used to fetch |
| 1411 | the actual URL. For 401 response codes (authentication required), basic HTTP |
| 1412 | authentication is performed. For the 30x response codes, recursion is bounded |
| 1413 | by the value of the *maxtries* attribute, which defaults to 10. |
| 1414 | |
| 1415 | For all other response codes, the method :meth:`http_error_default` is called |
| 1416 | which you can override in subclasses to handle the error appropriately. |
| 1417 | |
| 1418 | .. note:: |
| 1419 | |
| 1420 | According to the letter of :rfc:`2616`, 301 and 302 responses to POST requests |
| 1421 | must not be automatically redirected without confirmation by the user. In |
| 1422 | reality, browsers do allow automatic redirection of these responses, changing |
| 1423 | the POST to a GET, and :mod:`urllib` reproduces this behaviour. |
| 1424 | |
| 1425 | The parameters to the constructor are the same as those for :class:`URLopener`. |
| 1426 | |
| 1427 | .. note:: |
| 1428 | |
| 1429 | When performing basic authentication, a :class:`FancyURLopener` instance calls |
| 1430 | its :meth:`prompt_user_passwd` method. The default implementation asks the |
| 1431 | users for the required information on the controlling terminal. A subclass may |
| 1432 | override this method to support more appropriate behavior if needed. |
| 1433 | |
| 1434 | The :class:`FancyURLopener` class offers one additional method that should be |
| 1435 | overloaded to provide the appropriate behavior: |
| 1436 | |
| 1437 | .. method:: prompt_user_passwd(host, realm) |
| 1438 | |
| 1439 | Return information needed to authenticate the user at the given host in the |
| 1440 | specified security realm. The return value should be a tuple, ``(user, |
| 1441 | password)``, which can be used for basic authentication. |
| 1442 | |
| 1443 | The implementation prompts for this information on the terminal; an application |
| 1444 | should override this method to use an appropriate interaction model in the local |
| 1445 | environment. |
| 1446 | |
| 1447 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1448 | :mod:`urllib.request` Restrictions |
| 1449 | ---------------------------------- |
| 1450 | |
| 1451 | .. index:: |
| 1452 | pair: HTTP; protocol |
| 1453 | pair: FTP; protocol |
| 1454 | |
Florent Xicluna | 83386da | 2011-10-28 22:03:55 +0200 | [diff] [blame] | 1455 | * Currently, only the following protocols are supported: HTTP (versions 0.9 and |
Antoine Pitrou | df204be | 2012-11-24 17:59:08 +0100 | [diff] [blame] | 1456 | 1.0), FTP, local files, and data URLs. |
| 1457 | |
| 1458 | .. versionchanged:: 3.4 Added support for data URLs. |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1459 | |
Florent Xicluna | 305bb66 | 2011-10-28 22:14:41 +0200 | [diff] [blame] | 1460 | * The caching feature of :func:`urlretrieve` has been disabled until someone |
| 1461 | finds the time to hack proper processing of Expiration time headers. |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1462 | |
| 1463 | * There should be a function to query whether a particular URL is in the cache. |
| 1464 | |
| 1465 | * For backward compatibility, if a URL appears to point to a local file but the |
| 1466 | file can't be opened, the URL is re-interpreted using the FTP protocol. This |
| 1467 | can sometimes cause confusing error messages. |
| 1468 | |
| 1469 | * The :func:`urlopen` and :func:`urlretrieve` functions can cause arbitrarily |
| 1470 | long delays while waiting for a network connection to be set up. This means |
| 1471 | that it is difficult to build an interactive Web client using these functions |
| 1472 | without using threads. |
| 1473 | |
| 1474 | .. index:: |
| 1475 | single: HTML |
| 1476 | pair: HTTP; protocol |
| 1477 | |
| 1478 | * The data returned by :func:`urlopen` or :func:`urlretrieve` is the raw data |
| 1479 | returned by the server. This may be binary data (such as an image), plain text |
| 1480 | or (for example) HTML. The HTTP protocol provides type information in the reply |
| 1481 | header, which can be inspected by looking at the :mailheader:`Content-Type` |
| 1482 | header. If the returned data is HTML, you can use the module |
| 1483 | :mod:`html.parser` to parse it. |
| 1484 | |
| 1485 | .. index:: single: FTP |
| 1486 | |
| 1487 | * The code handling the FTP protocol cannot differentiate between a file and a |
| 1488 | directory. This can lead to unexpected behavior when attempting to read a URL |
| 1489 | that points to a file that is not accessible. If the URL ends in a ``/``, it is |
| 1490 | assumed to refer to a directory and will be handled accordingly. But if an |
| 1491 | attempt to read a file leads to a 550 error (meaning the URL cannot be found or |
| 1492 | is not accessible, often for permission reasons), then the path is treated as a |
| 1493 | directory in order to handle the case when a directory is specified by a URL but |
| 1494 | the trailing ``/`` has been left off. This can cause misleading results when |
| 1495 | you try to fetch a file whose read permissions make it inaccessible; the FTP |
| 1496 | code will try to read it, fail with a 550 error, and then perform a directory |
| 1497 | listing for the unreadable file. If fine-grained control is needed, consider |
Éric Araujo | 09eb980 | 2011-03-20 18:30:37 +0100 | [diff] [blame] | 1498 | using the :mod:`ftplib` module, subclassing :class:`FancyURLopener`, or changing |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1499 | *_urlopener* to meet your needs. |
| 1500 | |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 1501 | |
| 1502 | |
Georg Brandl | 8175dae | 2010-11-29 14:53:15 +0000 | [diff] [blame] | 1503 | :mod:`urllib.response` --- Response classes used by urllib |
| 1504 | ========================================================== |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 1505 | |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1506 | .. module:: urllib.response |
| 1507 | :synopsis: Response classes used by urllib. |
| 1508 | |
| 1509 | The :mod:`urllib.response` module defines functions and classes which define a |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 1510 | minimal file like interface, including ``read()`` and ``readline()``. The |
Ezio Melotti | b970142 | 2010-11-18 19:48:27 +0000 | [diff] [blame] | 1511 | typical response object is an addinfourl instance, which defines an ``info()`` |
Georg Brandl | 0f7ede4 | 2008-06-23 11:23:31 +0000 | [diff] [blame] | 1512 | method and that returns headers and a ``geturl()`` method that returns the url. |
Senthil Kumaran | aca8fd7 | 2008-06-23 04:41:59 +0000 | [diff] [blame] | 1513 | Functions defined by this module are used internally by the |
| 1514 | :mod:`urllib.request` module. |
| 1515 | |