mirror of https://github.com/python/cpython.git
128 lines
4.3 KiB
TeX
128 lines
4.3 KiB
TeX
\section{Standard Module \sectcode{httplib}}
|
|
\label{module-httplib}
|
|
\stmodindex{httplib}
|
|
\indexii{HTTP}{protocol}
|
|
|
|
|
|
This module defines a class which implements the client side of the
|
|
HTTP protocol. It is normally not used directly --- the module
|
|
\module{urllib}\refstmodindex{urllib} uses it to handle URLs that use
|
|
HTTP.
|
|
|
|
The module defines one class, \class{HTTP}. An \class{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{\var{host}:\var{port}}, else the default HTTP port (80)
|
|
is used. If no host is passed, no connection is made, and the
|
|
\method{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:
|
|
|
|
\begin{verbatim}
|
|
>>> h1 = httplib.HTTP('www.cwi.nl')
|
|
>>> h2 = httplib.HTTP('www.cwi.nl:80')
|
|
>>> h3 = httplib.HTTP('www.cwi.nl', 80)
|
|
\end{verbatim}
|
|
|
|
Once an \class{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 \method{putrequest()} method.
|
|
|
|
\item[2.] Make zero or more calls to the \method{putheader()} method.
|
|
|
|
\item[3.] Call the \method{endheaders()} method (this can be omitted if
|
|
step 4 makes no calls).
|
|
|
|
\item[4.] Optional calls to the \method{send()} method.
|
|
|
|
\item[5.] Call the \method{getreply()} method.
|
|
|
|
\item[6.] Call the \method{getfile()} method and read the data off the
|
|
file object that it returns.
|
|
|
|
\end{enumerate}
|
|
|
|
\subsection{HTTP Objects}
|
|
|
|
\class{HTTP} instances have the following methods:
|
|
|
|
\setindexsubitem{(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
|
|
\method{endheaders()} method has been called and before
|
|
\method{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
|
|
\code{(\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 \class{mimetools.Message} containing the
|
|
headers received from the server. See the description of the
|
|
\module{mimetools}\refstmodindex{mimetools} module.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{getfile}{}
|
|
Return a file object from which the data returned by the server can be
|
|
read, using the \method{read()}, \method{readline()} or
|
|
\method{readlines()} methods.
|
|
\end{funcdesc}
|
|
|
|
\subsection{Example}
|
|
\nodename{HTTP Example}
|
|
|
|
Here is an example session:
|
|
|
|
\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}
|