266 lines
8.2 KiB
TeX
266 lines
8.2 KiB
TeX
\section{\module{httplib} ---
|
|
HTTP protocol client}
|
|
|
|
\declaremodule{standard}{httplib}
|
|
\modulesynopsis{HTTP and HTTPS protocol client (requires sockets).}
|
|
|
|
\indexii{HTTP}{protocol}
|
|
\index{HTTP!\module{httplib} (standard module)}
|
|
|
|
This module defines classes which implement the client side of the
|
|
HTTP and HTTPS protocols. It is normally not used directly --- the
|
|
module \refmodule{urllib}\refstmodindex{urllib} uses it to handle URLs
|
|
that use HTTP and HTTPS.
|
|
|
|
\begin{notice}
|
|
HTTPS support is only available if the \refmodule{socket} module was
|
|
compiled with SSL support.
|
|
\end{notice}
|
|
|
|
\begin{notice}
|
|
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.
|
|
\end{notice}
|
|
|
|
The constants defined in this module are:
|
|
|
|
\begin{datadesc}{HTTP_PORT}
|
|
The default port for the HTTP protocol (always \code{80}).
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{HTTPS_PORT}
|
|
The default port for the HTTPS protocol (always \code{443}).
|
|
\end{datadesc}
|
|
|
|
The module provides the following classes:
|
|
|
|
\begin{classdesc}{HTTPConnection}{host\optional{, port}}
|
|
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 \code{\var{host}:\var{port}}, else the default HTTP port (80) is
|
|
used. For example, the following calls all create instances that connect to
|
|
the server at the same host and port:
|
|
|
|
\begin{verbatim}
|
|
>>> h1 = httplib.HTTPConnection('www.cwi.nl')
|
|
>>> h2 = httplib.HTTPConnection('www.cwi.nl:80')
|
|
>>> h3 = httplib.HTTPConnection('www.cwi.nl', 80)
|
|
\end{verbatim}
|
|
\versionadded{2.0}
|
|
\end{classdesc}
|
|
|
|
\begin{classdesc}{HTTPSConnection}{host\optional{, port, key_file, cert_file}}
|
|
A subclass of \class{HTTPConnection} that uses SSL for communication with
|
|
secure servers. Default port is \code{443}.
|
|
\var{key_file} is
|
|
the name of a PEM formatted file that contains your private
|
|
key. \var{cert_file} is a PEM formatted certificate chain file.
|
|
|
|
\warning{This does not do any certificate verification!}
|
|
|
|
\versionadded{2.0}
|
|
\end{classdesc}
|
|
|
|
\begin{classdesc}{HTTPResponse}{sock\optional{, debuglevel=0}\optional{, strict=0}}
|
|
Class whose instances are returned upon successful connection. Not
|
|
instantiated directly by user.
|
|
\versionadded{2.0}
|
|
\end{classdesc}
|
|
|
|
The following exceptions are raised as appropriate:
|
|
|
|
\begin{excdesc}{HTTPException}
|
|
The base class of the other exceptions in this module. It is a
|
|
subclass of \exception{Exception}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{NotConnected}
|
|
A subclass of \exception{HTTPException}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{InvalidURL}
|
|
A subclass of \exception{HTTPException}, raised if a port is given and is
|
|
either non-numeric or empty.
|
|
\versionadded{2.3}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{UnknownProtocol}
|
|
A subclass of \exception{HTTPException}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{UnknownTransferEncoding}
|
|
A subclass of \exception{HTTPException}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{UnimplementedFileMode}
|
|
A subclass of \exception{HTTPException}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{IncompleteRead}
|
|
A subclass of \exception{HTTPException}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{ImproperConnectionState}
|
|
A subclass of \exception{HTTPException}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{CannotSendRequest}
|
|
A subclass of \exception{ImproperConnectionState}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{CannotSendHeader}
|
|
A subclass of \exception{ImproperConnectionState}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{ResponseNotReady}
|
|
A subclass of \exception{ImproperConnectionState}.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
\begin{excdesc}{BadStatusLine}
|
|
A subclass of \exception{HTTPException}. Raised if a server responds with a
|
|
HTTP status code that we don't understand.
|
|
\versionadded{2.0}
|
|
\end{excdesc}
|
|
|
|
|
|
\subsection{HTTPConnection Objects \label{httpconnection-objects}}
|
|
|
|
\class{HTTPConnection} instances have the following methods:
|
|
|
|
\begin{methoddesc}{request}{method, url\optional{, body\optional{, headers}}}
|
|
This will send a request to the server using the HTTP request method
|
|
\var{method} and the selector \var{url}. If the \var{body} argument is
|
|
present, it should be a string of data to send after the headers are finished.
|
|
The header Content-Length is automatically set to the correct value.
|
|
The \var{headers} argument should be a mapping of extra HTTP headers to send
|
|
with the request.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{getresponse}{}
|
|
Should be called after a request is sent to get the response from the server.
|
|
Returns an \class{HTTPResponse} instance.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{set_debuglevel}{level}
|
|
Set the debugging level (the amount of debugging output printed).
|
|
The default debug level is \code{0}, meaning no debugging output is
|
|
printed.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{connect}{}
|
|
Connect to the server specified when the object was created.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{close}{}
|
|
Close the connection to the server.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{send}{data}
|
|
Send data to the server. This should be used directly only after the
|
|
\method{endheaders()} method has been called and before
|
|
\method{getreply()} has been called.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{putrequest}{request, selector\optional{,
|
|
skip\_host\optional{, 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
|
|
\var{request} string, the \var{selector} string, and the HTTP version
|
|
(\code{HTTP/1.1}). To disable automatic sending of \code{Host:} or
|
|
\code{Accept-Encoding:} headers (for example to accept additional
|
|
content encodings), specify \var{skip_host} or \var{skip_accept_encoding}
|
|
with non-False values.
|
|
\versionchanged[\var{skip_accept_encoding} argument added]{2.4}
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{putheader}{header, argument\optional{, ...}}
|
|
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.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{endheaders}{}
|
|
Send a blank line to the server, signalling the end of the headers.
|
|
\end{methoddesc}
|
|
|
|
|
|
\subsection{HTTPResponse Objects \label{httpresponse-objects}}
|
|
|
|
\class{HTTPResponse} instances have the following methods and attributes:
|
|
|
|
\begin{methoddesc}{read}{\optional{amt}}
|
|
Reads and returns the response body, or up to the next \var{amt} bytes.
|
|
\end{methoddesc}
|
|
|
|
\begin{methoddesc}{getheader}{name\optional{, default}}
|
|
Get the contents of the header \var{name}, or \var{default} if there is no
|
|
matching header.
|
|
\end{methoddesc}
|
|
|
|
\begin{datadesc}{msg}
|
|
A \class{mimetools.Message} instance containing the response headers.
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{version}
|
|
HTTP protocol version used by server. 10 for HTTP/1.0, 11 for HTTP/1.1.
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{status}
|
|
Status code returned by server.
|
|
\end{datadesc}
|
|
|
|
\begin{datadesc}{reason}
|
|
Reason phrase returned by server.
|
|
\end{datadesc}
|
|
|
|
|
|
\subsection{Examples \label{httplib-examples}}
|
|
|
|
Here is an example session that uses the \samp{GET} method:
|
|
|
|
\begin{verbatim}
|
|
>>> 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()
|
|
\end{verbatim}
|
|
|
|
Here is an example session that shows how to \samp{POST} requests:
|
|
|
|
\begin{verbatim}
|
|
>>> 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()
|
|
\end{verbatim}
|