mirror of
https://github.com/python/cpython.git
synced 2025-10-31 21:51:50 +00:00
128 lines
4.3 KiB
TeX
128 lines
4.3 KiB
TeX
\section{Standard Module \sectcode{httplib}}
|
|
\label{module-httplib}
|
|
\stmodindex{httplib}
|
|
\index{HTTP}
|
|
|
|
\renewcommand{\indexsubitem}{(in module httplib)}
|
|
|
|
This module defines a class which implements the client side of the
|
|
HTTP protocol. It is normally not used directly --- the module
|
|
\code{urllib} uses it to handle URLs that use HTTP.
|
|
\refstmodindex{urllib}
|
|
|
|
The module defines one class, \code{HTTP}. An \code{HTTP} 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{host:port}, else the default HTTP port (80) is used.
|
|
If no host is passed, no connection is made, and the \code{connect}
|
|
method should be used to connect to a server. For example, the
|
|
following calls all create instances that connect to the server at the
|
|
same host and port:
|
|
|
|
\bcode\begin{verbatim}
|
|
>>> h1 = httplib.HTTP('www.cwi.nl')
|
|
>>> h2 = httplib.HTTP('www.cwi.nl:80')
|
|
>>> h3 = httplib.HTTP('www.cwi.nl', 80)
|
|
\end{verbatim}\ecode
|
|
%
|
|
Once an \code{HTTP} instance has been connected to an HTTP server, it
|
|
should be used as follows:
|
|
|
|
\begin{enumerate}
|
|
|
|
\item[1.] Make exactly one call to the \code{putrequest()} method.
|
|
|
|
\item[2.] Make zero or more calls to the \code{putheader()} method.
|
|
|
|
\item[3.] Call the \code{endheaders()} method (this can be omitted if
|
|
step 4 makes no calls).
|
|
|
|
\item[4.] Optional calls to the \code{send()} method.
|
|
|
|
\item[5.] Call the \code{getreply()} method.
|
|
|
|
\item[6.] Call the \code{getfile()} method and read the data off the
|
|
file object that it returns.
|
|
|
|
\end{enumerate}
|
|
|
|
\subsection{HTTP Objects}
|
|
|
|
\code{HTTP} instances have the following methods:
|
|
|
|
\renewcommand{\indexsubitem}{(HTTP method)}
|
|
|
|
\begin{funcdesc}{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{funcdesc}
|
|
|
|
\begin{funcdesc}{connect}{host\optional{\, port}}
|
|
Connect to the server given by \var{host} and \var{port}. See the
|
|
intro for the default port. This should be called directly only if
|
|
the instance was instantiated without passing a host.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{send}{data}
|
|
Send data to the server. This should be used directly only after the
|
|
\code{endheaders()} method has been called and before
|
|
\code{getreply()} has been called.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{putrequest}{request\, selector}
|
|
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/1.0}).
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{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{funcdesc}
|
|
|
|
\begin{funcdesc}{endheaders}{}
|
|
Send a blank line to the server, signalling the end of the headers.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{getreply}{}
|
|
Complete the request by shutting down the sending end of the socket,
|
|
read the reply from the server, and return a triple (\var{replycode},
|
|
\var{message}, \var{headers}). Here \var{replycode} is the integer
|
|
reply code from the request (e.g.\ \code{200} if the request was
|
|
handled properly); \var{message} is the message string corresponding
|
|
to the reply code; and \var{headers} is an instance of the class
|
|
\code{mimetools.Message} containing the headers received from the server.
|
|
See the description of the \code{mimetools} module.
|
|
\refstmodindex{mimetools}
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{getfile}{}
|
|
Return a file object from which the data returned by the server can be
|
|
read, using the \code{read()}, \code{readline()} or \code{readlines()}
|
|
methods.
|
|
\end{funcdesc}
|
|
|
|
\subsection{Example}
|
|
\nodename{HTTP Example}
|
|
|
|
Here is an example session:
|
|
|
|
\bcode\begin{verbatim}
|
|
>>> import httplib
|
|
>>> h = httplib.HTTP('www.cwi.nl')
|
|
>>> h.putrequest('GET', '/index.html')
|
|
>>> h.putheader('Accept', 'text/html')
|
|
>>> h.putheader('Accept', 'text/plain')
|
|
>>> h.endheaders()
|
|
>>> errcode, errmsg, headers = h.getreply()
|
|
>>> print errcode # Should be 200
|
|
>>> f = h.getfile()
|
|
>>> data = f.read() # Get the raw HTML
|
|
>>> f.close()
|
|
>>>
|
|
\end{verbatim}\ecode
|