cpython/Doc/library/robotparser.rst

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:mod:`robotparser` --- Parser for robots.txt
=============================================
.. module:: robotparser
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:synopsis: Loads a robots.txt file and answers questions about
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fetchability of other URLs.
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.. sectionauthor:: Skip Montanaro <skip@pobox.com>
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.. index::
single: WWW
single: World Wide Web
single: URL
single: robots.txt
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.. note::
The :mod:`robotparser` module has been renamed :mod:`urllib.robotparser` in
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Python 3.
The :term:`2to3` tool will automatically adapt imports when converting
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your sources to Python 3.
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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.
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.. class:: RobotFileParser()
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This class provides a set of methods to read, parse and answer questions
about a single :file:`robots.txt` file.
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.. method:: set_url(url)
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Sets the URL referring to a :file:`robots.txt` file.
.. method:: read()
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Reads the :file:`robots.txt` URL and feeds it to the parser.
.. method:: parse(lines)
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Parses the lines argument.
.. method:: can_fetch(useragent, url)
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Returns ``True`` if the *useragent* is allowed to fetch the *url*
according to the rules contained in the parsed :file:`robots.txt`
file.
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.. method:: mtime()
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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.
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.. method:: modified()
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Sets the time the ``robots.txt`` file was last fetched to the current
time.
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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