107 lines
3.2 KiB
ReStructuredText
107 lines
3.2 KiB
ReStructuredText
:mod:`urllib.robotparser` --- Parser for robots.txt
|
|
====================================================
|
|
|
|
.. module:: urllib.robotparser
|
|
:synopsis: Load a robots.txt file and answer questions about
|
|
fetchability of other URLs.
|
|
|
|
.. sectionauthor:: Skip Montanaro <skip@pobox.com>
|
|
|
|
**Source code:** :source:`Lib/urllib/robotparser.py`
|
|
|
|
.. index::
|
|
single: WWW
|
|
single: World Wide Web
|
|
single: URL
|
|
single: robots.txt
|
|
|
|
--------------
|
|
|
|
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(url='')
|
|
|
|
This class provides methods to read, parse and answer questions about the
|
|
:file:`robots.txt` file at *url*.
|
|
|
|
.. 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.
|
|
|
|
.. method:: crawl_delay(useragent)
|
|
|
|
Returns the value of the ``Crawl-delay`` parameter from ``robots.txt``
|
|
for the *useragent* in question. If there is no such parameter or it
|
|
doesn't apply to the *useragent* specified or the ``robots.txt`` entry
|
|
for this parameter has invalid syntax, return ``None``.
|
|
|
|
.. versionadded:: 3.6
|
|
|
|
.. method:: request_rate(useragent)
|
|
|
|
Returns the contents of the ``Request-rate`` parameter from
|
|
``robots.txt`` as a :term:`named tuple` ``RequestRate(requests, seconds)``.
|
|
If there is no such parameter or it doesn't apply to the *useragent*
|
|
specified or the ``robots.txt`` entry for this parameter has invalid
|
|
syntax, return ``None``.
|
|
|
|
.. versionadded:: 3.6
|
|
|
|
.. method:: site_maps()
|
|
|
|
Returns the contents of the ``Sitemap`` parameter from
|
|
``robots.txt`` in the form of a :func:`list`. If there is no such
|
|
parameter or the ``robots.txt`` entry for this parameter has
|
|
invalid syntax, return ``None``.
|
|
|
|
.. versionadded:: 3.8
|
|
|
|
|
|
The following example demonstrates basic use of the :class:`RobotFileParser`
|
|
class::
|
|
|
|
>>> import urllib.robotparser
|
|
>>> rp = urllib.robotparser.RobotFileParser()
|
|
>>> rp.set_url("http://www.musi-cal.com/robots.txt")
|
|
>>> rp.read()
|
|
>>> rrate = rp.request_rate("*")
|
|
>>> rrate.requests
|
|
3
|
|
>>> rrate.seconds
|
|
20
|
|
>>> rp.crawl_delay("*")
|
|
6
|
|
>>> rp.can_fetch("*", "http://www.musi-cal.com/cgi-bin/search?city=San+Francisco")
|
|
False
|
|
>>> rp.can_fetch("*", "http://www.musi-cal.com/")
|
|
True
|