:mod:`robotparser` ---  Parser for robots.txt

=============================================

.. module:: robotparser

   :synopsis: Loads a robots.txt file and answers questions about

              fetchability of other URLs.

.. sectionauthor:: Skip Montanaro <skip@pobox.com>

.. index::

   single: WWW

   single: World Wide Web

   single: URL

   single: robots.txt

.. note::

   The :mod:`robotparser` module has been renamed :mod:`urllib.robotparser` in

   Python 3.0.

   The :term:`2to3` tool will automatically adapt imports when converting

   your sources to 3.0.

This module provides a single class, :class:`RobotFileParser`, which answers

questions about whether or not a particular user agent can fetch a URL on the

Web site that published the :file:`robots.txt` file.  For more details on the

structure of :file:`robots.txt` files, see http://www.robotstxt.org/orig.html.

.. class:: RobotFileParser()

   This class provides a set of methods to read, parse and answer questions

   about a single :file:`robots.txt` file.

   .. method:: set_url(url)

      Sets the URL referring to a :file:`robots.txt` file.

   .. method:: read()

      Reads the :file:`robots.txt` URL and feeds it to the parser.

   .. method:: parse(lines)

      Parses the lines argument.

   .. method:: can_fetch(useragent, url)

      Returns ``True`` if the *useragent* is allowed to fetch the *url*

      according to the rules contained in the parsed :file:`robots.txt`

      file.

   .. method:: mtime()

      Returns the time the ``robots.txt`` file was last fetched.  This is

      useful for long-running web spiders that need to check for new

      ``robots.txt`` files periodically.

   .. method:: modified()

      Sets the time the ``robots.txt`` file was last fetched to the current

      time.

The following example demonstrates basic use of the RobotFileParser class. ::

   >>> import robotparser

   >>> rp = robotparser.RobotFileParser()

   >>> rp.set_url("http://www.musi-cal.com/robots.txt")

   >>> rp.read()

   >>> rp.can_fetch("*", "http://www.musi-cal.com/cgi-bin/search?city=San+Francisco")

   False

   >>> rp.can_fetch("*", "http://www.musi-cal.com/")

   True