Python 3.6.5 Documentation >  "urllib.robotparser" — Parser for robots.txt

"urllib.robotparser" — Parser for robots.txt
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**Source code:** Lib/urllib/robotparser.py

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This module provides a single class, "RobotFileParser", which answers
questions about whether or not a particular user agent can fetch a URL
on the Web site that published the "robots.txt" file. For more
details on the structure of "robots.txt" files, see
http://www.robotstxt.org/orig.html.

class urllib.robotparser.RobotFileParser(url='')

This class provides methods to read, parse and answer questions
about the "robots.txt" file at *url*.

set_url(url)

Sets the URL referring to a "robots.txt" file.

read()

Reads the "robots.txt" URL and feeds it to the parser.

parse(lines)

Parses the lines argument.

can_fetch(useragent, url)

Returns "True" if the *useragent* is allowed to fetch the *url*
according to the rules contained in the parsed "robots.txt"
file.

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.

modified()

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

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".

New in version 3.6.

request_rate(useragent)

Returns the contents of the "Request-rate" parameter from
"robots.txt" as a *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".

New in version 3.6.

The following example demonstrates basic use of the "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