cpython/Doc/library/httplib.rst

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2007-08-15 11:28:01 -03:00
:mod:`httplib` --- HTTP protocol client
=======================================
.. module:: httplib
:synopsis: HTTP and HTTPS protocol client (requires sockets).
.. note::
The :mod:`httplib` module has been renamed to :mod:`http.client` in Python
3.0. The :term:`2to3` tool will automatically adapt imports when converting
your sources to 3.0.
2007-08-15 11:28:01 -03:00
.. index::
pair: HTTP; protocol
single: HTTP; httplib (standard module)
.. index:: module: urllib
This module defines classes which implement the client side of the HTTP and
HTTPS protocols. It is normally not used directly --- the module :mod:`urllib`
uses it to handle URLs that use HTTP and HTTPS.
.. note::
HTTPS support is only available if the :mod:`socket` module was compiled with
SSL support.
.. note::
The public interface for this module changed substantially in Python 2.0. The
:class:`HTTP` class is retained only for backward compatibility with 1.5.2. It
should not be used in new code. Refer to the online docstrings for usage.
The module provides the following classes:
.. class:: HTTPConnection(host[, port[, strict[, timeout]]])
An :class:`HTTPConnection` instance represents one transaction with an HTTP
server. It should be instantiated passing it a host and optional port
number. If no port number is passed, the port is extracted from the host
string if it has the form ``host:port``, else the default HTTP port (80) is
used. When True, the optional parameter *strict* (which defaults to a false
value) causes ``BadStatusLine`` to
be raised if the status line can't be parsed as a valid HTTP/1.0 or 1.1
status line. If the optional *timeout* parameter is given, blocking
operations (like connection attempts) will timeout after that many seconds
(if it is not given, the global default timeout setting is used).
2007-08-15 11:28:01 -03:00
For example, the following calls all create instances that connect to the server
at the same host and port::
>>> h1 = httplib.HTTPConnection('www.cwi.nl')
>>> h2 = httplib.HTTPConnection('www.cwi.nl:80')
>>> h3 = httplib.HTTPConnection('www.cwi.nl', 80)
>>> h3 = httplib.HTTPConnection('www.cwi.nl', 80, timeout=10)
.. versionadded:: 2.0
.. versionchanged:: 2.6
*timeout* was added.
.. class:: HTTPSConnection(host[, port[, key_file[, cert_file[, strict[, timeout]]]]])
A subclass of :class:`HTTPConnection` that uses SSL for communication with
secure servers. Default port is ``443``. *key_file* is the name of a PEM
formatted file that contains your private key. *cert_file* is a PEM formatted
certificate chain file.
.. warning::
This does not do any certificate verification!
.. versionadded:: 2.0
.. versionchanged:: 2.6
*timeout* was added.
.. class:: HTTPResponse(sock[, debuglevel=0][, strict=0])
Class whose instances are returned upon successful connection. Not instantiated
directly by user.
.. versionadded:: 2.0
The following exceptions are raised as appropriate:
.. exception:: HTTPException
The base class of the other exceptions in this module. It is a subclass of
:exc:`Exception`.
.. versionadded:: 2.0
.. exception:: NotConnected
A subclass of :exc:`HTTPException`.
.. versionadded:: 2.0
.. exception:: InvalidURL
A subclass of :exc:`HTTPException`, raised if a port is given and is either
non-numeric or empty.
.. versionadded:: 2.3
.. exception:: UnknownProtocol
A subclass of :exc:`HTTPException`.
.. versionadded:: 2.0
.. exception:: UnknownTransferEncoding
A subclass of :exc:`HTTPException`.
.. versionadded:: 2.0
.. exception:: UnimplementedFileMode
A subclass of :exc:`HTTPException`.
.. versionadded:: 2.0
.. exception:: IncompleteRead
A subclass of :exc:`HTTPException`.
.. versionadded:: 2.0
.. exception:: ImproperConnectionState
A subclass of :exc:`HTTPException`.
.. versionadded:: 2.0
.. exception:: CannotSendRequest
A subclass of :exc:`ImproperConnectionState`.
.. versionadded:: 2.0
.. exception:: CannotSendHeader
A subclass of :exc:`ImproperConnectionState`.
.. versionadded:: 2.0
.. exception:: ResponseNotReady
A subclass of :exc:`ImproperConnectionState`.
.. versionadded:: 2.0
.. exception:: BadStatusLine
A subclass of :exc:`HTTPException`. Raised if a server responds with a HTTP
status code that we don't understand.
.. versionadded:: 2.0
The constants defined in this module are:
.. data:: HTTP_PORT
The default port for the HTTP protocol (always ``80``).
.. data:: HTTPS_PORT
The default port for the HTTPS protocol (always ``443``).
and also the following constants for integer status codes:
+------------------------------------------+---------+-----------------------------------------------------------------------+
| Constant | Value | Definition |
+==========================================+=========+=======================================================================+
| :const:`CONTINUE` | ``100`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.1.1 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.1.1>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`SWITCHING_PROTOCOLS` | ``101`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.1.2 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.1.2>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`PROCESSING` | ``102`` | WEBDAV, `RFC 2518, Section 10.1 |
| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_102>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`OK` | ``200`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.2.1 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.1>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`CREATED` | ``201`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.2.2 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.2>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`ACCEPTED` | ``202`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.2.3 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.3>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`NON_AUTHORITATIVE_INFORMATION` | ``203`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.2.4 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.4>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`NO_CONTENT` | ``204`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.2.5 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.5>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`RESET_CONTENT` | ``205`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.2.6 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.6>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`PARTIAL_CONTENT` | ``206`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.2.7 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.7>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`MULTI_STATUS` | ``207`` | WEBDAV `RFC 2518, Section 10.2 |
| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_207>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`IM_USED` | ``226`` | Delta encoding in HTTP, |
| | | :rfc:`3229`, Section 10.4.1 |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`MULTIPLE_CHOICES` | ``300`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.3.1 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.1>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`MOVED_PERMANENTLY` | ``301`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.3.2 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.2>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`FOUND` | ``302`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.3.3 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.3>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`SEE_OTHER` | ``303`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.3.4 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.4>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`NOT_MODIFIED` | ``304`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.3.5 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.5>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`USE_PROXY` | ``305`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.3.6 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.6>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`TEMPORARY_REDIRECT` | ``307`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.3.8 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.8>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`BAD_REQUEST` | ``400`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.1 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.1>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`UNAUTHORIZED` | ``401`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.2 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.2>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`PAYMENT_REQUIRED` | ``402`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.3 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.3>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`FORBIDDEN` | ``403`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.4 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.4>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`NOT_FOUND` | ``404`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.5 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.5>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`METHOD_NOT_ALLOWED` | ``405`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.6 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.6>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`NOT_ACCEPTABLE` | ``406`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.7 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.7>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`PROXY_AUTHENTICATION_REQUIRED` | ``407`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.8 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.8>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`REQUEST_TIMEOUT` | ``408`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.9 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.9>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`CONFLICT` | ``409`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.10 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.10>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`GONE` | ``410`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.11 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.11>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`LENGTH_REQUIRED` | ``411`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.12 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.12>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`PRECONDITION_FAILED` | ``412`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.13 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.13>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`REQUEST_ENTITY_TOO_LARGE` | ``413`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.14 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.14>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`REQUEST_URI_TOO_LONG` | ``414`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.15 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.15>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`UNSUPPORTED_MEDIA_TYPE` | ``415`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.16 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.16>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`REQUESTED_RANGE_NOT_SATISFIABLE` | ``416`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.17 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.17>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`EXPECTATION_FAILED` | ``417`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.4.18 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.18>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`UNPROCESSABLE_ENTITY` | ``422`` | WEBDAV, `RFC 2518, Section 10.3 |
| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_422>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`LOCKED` | ``423`` | WEBDAV `RFC 2518, Section 10.4 |
| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_423>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`FAILED_DEPENDENCY` | ``424`` | WEBDAV, `RFC 2518, Section 10.5 |
| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_424>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`UPGRADE_REQUIRED` | ``426`` | HTTP Upgrade to TLS, |
| | | :rfc:`2817`, Section 6 |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`INTERNAL_SERVER_ERROR` | ``500`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.5.1 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.1>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`NOT_IMPLEMENTED` | ``501`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.5.2 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.2>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`BAD_GATEWAY` | ``502`` | HTTP/1.1 `RFC 2616, Section |
| | | 10.5.3 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.3>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`SERVICE_UNAVAILABLE` | ``503`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.5.4 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.4>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`GATEWAY_TIMEOUT` | ``504`` | HTTP/1.1 `RFC 2616, Section |
| | | 10.5.5 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.5>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`HTTP_VERSION_NOT_SUPPORTED` | ``505`` | HTTP/1.1, `RFC 2616, Section |
| | | 10.5.6 |
| | | <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.6>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`INSUFFICIENT_STORAGE` | ``507`` | WEBDAV, `RFC 2518, Section 10.6 |
| | | <http://www.webdav.org/specs/rfc2518.html#STATUS_507>`_ |
+------------------------------------------+---------+-----------------------------------------------------------------------+
| :const:`NOT_EXTENDED` | ``510`` | An HTTP Extension Framework, |
| | | :rfc:`2774`, Section 7 |
+------------------------------------------+---------+-----------------------------------------------------------------------+
.. data:: responses
This dictionary maps the HTTP 1.1 status codes to the W3C names.
Example: ``httplib.responses[httplib.NOT_FOUND]`` is ``'Not Found'``.
.. versionadded:: 2.5
.. _httpconnection-objects:
HTTPConnection Objects
----------------------
:class:`HTTPConnection` instances have the following methods:
.. method:: HTTPConnection.request(method, url[, body[, headers]])
This will send a request to the server using the HTTP request method *method*
and the selector *url*. If the *body* argument is present, it should be a
string of data to send after the headers are finished. Alternatively, it may
be an open file object, in which case the contents of the file is sent; this
file object should support ``fileno()`` and ``read()`` methods. The header
Content-Length is automatically set to the correct value. The *headers*
argument should be a mapping of extra HTTP headers to send with the request.
.. versionchanged:: 2.6
*body* can be a file object.
.. method:: HTTPConnection.getresponse()
Should be called after a request is sent to get the response from the server.
Returns an :class:`HTTPResponse` instance.
.. note::
Note that you must have read the whole response before you can send a new
request to the server.
.. method:: HTTPConnection.set_debuglevel(level)
Set the debugging level (the amount of debugging output printed). The default
debug level is ``0``, meaning no debugging output is printed.
.. method:: HTTPConnection.connect()
Connect to the server specified when the object was created.
.. method:: HTTPConnection.close()
Close the connection to the server.
As an alternative to using the :meth:`request` method described above, you can
also send your request step by step, by using the four functions below.
.. method:: HTTPConnection.putrequest(request, selector[, skip_host[, skip_accept_encoding]])
This should be the first call after the connection to the server has been made.
It sends a line to the server consisting of the *request* string, the *selector*
string, and the HTTP version (``HTTP/1.1``). To disable automatic sending of
``Host:`` or ``Accept-Encoding:`` headers (for example to accept additional
content encodings), specify *skip_host* or *skip_accept_encoding* with non-False
values.
.. versionchanged:: 2.4
*skip_accept_encoding* argument added.
.. method:: HTTPConnection.putheader(header, argument[, ...])
Send an :rfc:`822`\ -style header to the server. It sends a line to the server
consisting of the header, a colon and a space, and the first argument. If more
arguments are given, continuation lines are sent, each consisting of a tab and
an argument.
.. method:: HTTPConnection.endheaders()
Send a blank line to the server, signalling the end of the headers.
.. method:: HTTPConnection.send(data)
Send data to the server. This should be used directly only after the
:meth:`endheaders` method has been called and before :meth:`getresponse` is
called.
.. _httpresponse-objects:
HTTPResponse Objects
--------------------
:class:`HTTPResponse` instances have the following methods and attributes:
.. method:: HTTPResponse.read([amt])
Reads and returns the response body, or up to the next *amt* bytes.
.. method:: HTTPResponse.getheader(name[, default])
Get the contents of the header *name*, or *default* if there is no matching
header.
.. method:: HTTPResponse.getheaders()
Return a list of (header, value) tuples.
.. versionadded:: 2.4
.. attribute:: HTTPResponse.msg
A :class:`mimetools.Message` instance containing the response headers.
.. attribute:: HTTPResponse.version
HTTP protocol version used by server. 10 for HTTP/1.0, 11 for HTTP/1.1.
.. attribute:: HTTPResponse.status
Status code returned by server.
.. attribute:: HTTPResponse.reason
Reason phrase returned by server.
.. _httplib-examples:
Examples
--------
Here is an example session that uses the ``GET`` method::
>>> import httplib
>>> conn = httplib.HTTPConnection("www.python.org")
>>> conn.request("GET", "/index.html")
>>> r1 = conn.getresponse()
>>> print r1.status, r1.reason
200 OK
>>> data1 = r1.read()
>>> conn.request("GET", "/parrot.spam")
>>> r2 = conn.getresponse()
>>> print r2.status, r2.reason
404 Not Found
>>> data2 = r2.read()
>>> conn.close()
Here is an example session that shows how to ``POST`` requests::
>>> import httplib, urllib
>>> params = urllib.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0})
>>> headers = {"Content-type": "application/x-www-form-urlencoded",
... "Accept": "text/plain"}
>>> conn = httplib.HTTPConnection("musi-cal.mojam.com:80")
>>> conn.request("POST", "/cgi-bin/query", params, headers)
>>> response = conn.getresponse()
>>> print response.status, response.reason
200 OK
>>> data = response.read()
>>> conn.close()