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\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 theHTTP and HTTPS protocols.  It is normally not used directly --- themodule \refmodule{urllib}\refstmodindex{urllib} uses it to handle URLsthat 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 module provides the following classes: \begin{classdesc}{HTTPConnection}{host\optional{, port}}An \class{HTTPConnection} instance represents one transaction with an HTTPserver.  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 ithas the form \code{\var{host}:\var{port}}, else the default HTTP port (80) isused.  For example, the following calls all create instances that connect tothe 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 withsecure servers.  Default port is \code{443}.\var{key_file} isthe name of a PEM formatted file that contains your privatekey. \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.  Notinstantiated 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 asubclass 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 iseither 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 aHTTP status code that we don't understand.\versionadded{2.0}\end{excdesc} 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} and also the following constants for integer status codes: \begin{tableiii}{l|c|l}{constant}{Constant}{Value}{Definition}  \lineiii{CONTINUE}{\code{100}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.1.1}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.1.1}}  \lineiii{SWITCHING_PROTOCOLS}{\code{101}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.1.2}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.1.2}}  \lineiii{PROCESSING}{\code{102}}    {WEBDAV, \ulink{RFC 2518, Section 10.1}      {http://www.webdav.org/specs/rfc2518.html#STATUS_102}}   \lineiii{OK}{\code{200}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.2.1}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.1}}  \lineiii{CREATED}{\code{201}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.2.2}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.2}}  \lineiii{ACCEPTED}{\code{202}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.2.3}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.3}}  \lineiii{NON_AUTHORITATIVE_INFORMATION}{\code{203}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.2.4}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.4}}  \lineiii{NO_CONTENT}{\code{204}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.2.5}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.5}}  \lineiii{RESET_CONTENT}{\code{205}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.2.6}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.6}}  \lineiii{PARTIAL_CONTENT}{\code{206}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.2.7}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.2.7}}  \lineiii{MULTI_STATUS}{\code{207}}    {WEBDAV \ulink{RFC 2518, Section 10.2}      {http://www.webdav.org/specs/rfc2518.html#STATUS_207}}  \lineiii{IM_USED}{\code{226}}    {Delta encoding in HTTP, \rfc{3229}, Section 10.4.1}   \lineiii{MULTIPLE_CHOICES}{\code{300}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.3.1}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.1}}  \lineiii{MOVED_PERMANENTLY}{\code{301}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.3.2}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.2}}  \lineiii{FOUND}{\code{302}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.3.3}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.3}}  \lineiii{SEE_OTHER}{\code{303}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.3.4}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.4}}  \lineiii{NOT_MODIFIED}{\code{304}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.3.5}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.5}}  \lineiii{USE_PROXY}{\code{305}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.3.6}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.6}}  \lineiii{TEMPORARY_REDIRECT}{\code{307}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.3.8}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.3.8}}   \lineiii{BAD_REQUEST}{\code{400}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.1}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.1}}  \lineiii{UNAUTHORIZED}{\code{401}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.2}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.2}}  \lineiii{PAYMENT_REQUIRED}{\code{402}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.3}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.3}}  \lineiii{FORBIDDEN}{\code{403}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.4}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.4}}  \lineiii{NOT_FOUND}{\code{404}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.5}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.5}}  \lineiii{METHOD_NOT_ALLOWED}{\code{405}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.6}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.6}}  \lineiii{NOT_ACCEPTABLE}{\code{406}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.7}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.7}}  \lineiii{PROXY_AUTHENTICATION_REQUIRED}    {\code{407}}{HTTP/1.1, \ulink{RFC 2616, Section 10.4.8}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.8}}  \lineiii{REQUEST_TIMEOUT}{\code{408}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.9}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.9}}  \lineiii{CONFLICT}{\code{409}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.10}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.10}}  \lineiii{GONE}{\code{410}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.11}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.11}}  \lineiii{LENGTH_REQUIRED}{\code{411}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.12}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.12}}  \lineiii{PRECONDITION_FAILED}{\code{412}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.13}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.13}}  \lineiii{REQUEST_ENTITY_TOO_LARGE}    {\code{413}}{HTTP/1.1, \ulink{RFC 2616, Section 10.4.14}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.14}}  \lineiii{REQUEST_URI_TOO_LONG}{\code{414}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.15}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.15}}  \lineiii{UNSUPPORTED_MEDIA_TYPE}{\code{415}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.16}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.16}}  \lineiii{REQUESTED_RANGE_NOT_SATISFIABLE}{\code{416}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.17}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.17}}  \lineiii{EXPECTATION_FAILED}{\code{417}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.4.18}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.18}}  \lineiii{UNPROCESSABLE_ENTITY}{\code{422}}    {WEBDAV, \ulink{RFC 2518, Section 10.3}      {http://www.webdav.org/specs/rfc2518.html#STATUS_422}}  \lineiii{LOCKED}{\code{423}}    {WEBDAV \ulink{RFC 2518, Section 10.4}      {http://www.webdav.org/specs/rfc2518.html#STATUS_423}}  \lineiii{FAILED_DEPENDENCY}{\code{424}}    {WEBDAV, \ulink{RFC 2518, Section 10.5}      {http://www.webdav.org/specs/rfc2518.html#STATUS_424}}  \lineiii{UPGRADE_REQUIRED}{\code{426}}    {HTTP Upgrade to TLS, \rfc{2817}, Section 6}   \lineiii{INTERNAL_SERVER_ERROR}{\code{500}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.5.1}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.1}}  \lineiii{NOT_IMPLEMENTED}{\code{501}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.5.2}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.2}}  \lineiii{BAD_GATEWAY}{\code{502}}    {HTTP/1.1 \ulink{RFC 2616, Section 10.5.3}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.3}}  \lineiii{SERVICE_UNAVAILABLE}{\code{503}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.5.4}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.4}}  \lineiii{GATEWAY_TIMEOUT}{\code{504}}    {HTTP/1.1 \ulink{RFC 2616, Section 10.5.5}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.5}}  \lineiii{HTTP_VERSION_NOT_SUPPORTED}{\code{505}}    {HTTP/1.1, \ulink{RFC 2616, Section 10.5.6}      {http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.6}}  \lineiii{INSUFFICIENT_STORAGE}{\code{507}}    {WEBDAV, \ulink{RFC 2518, Section 10.6}      {http://www.webdav.org/specs/rfc2518.html#STATUS_507}}  \lineiii{NOT_EXTENDED}{\code{510}}    {An HTTP Extension Framework, \rfc{2774}, Section 7}\end{tableiii} \begin{datadesc}{responses}This dictionary maps the HTTP 1.1 status codes to the W3C names. Example: \code{httplib.responses[httplib.NOT_FOUND]} is \code{'Not Found'}.\versionadded{2.5}\end{datadesc}  \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 ispresent, 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 sendwith 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.\note{Note that you must have read the whole response before you can send a newrequest to the server.}\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 isprinted.\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} As an alternative to using the \method{request()} method described above,you can also send your request step by step, by using the four functionsbelow. \begin{methoddesc}{putrequest}{request, selector\optional{,skip\_host\optional{, skip_accept_encoding}}}This should be the first call after the connection to the server hasbeen 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 additionalcontent 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 theserver consisting of the header, a colon and a space, and the firstargument.  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} \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{getresponse()} is called.\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 nomatching header.\end{methoddesc} \begin{methoddesc}{getheaders}{}Return a list of (header, value) tuples. \versionadded{2.4}\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.reason200 OK>>> data1 = r1.read()>>> conn.request("GET", "/parrot.spam")>>> r2 = conn.getresponse()>>> print r2.status, r2.reason404 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.reason200 OK>>> data = response.read()>>> conn.close()\end{verbatim}