urllib.robotparser — Parser for robots.txt

Python documentation

Source code:

Lib/urllib/robotparser.py

———
This module provides a single class,

RobotFileParser

, which answers questions about whether or not a particular user agent can fetch a URL on the website that published the robots.txt file. For more details on the structure of robots.txt files, see

RFC 9309

.

classurllib.robotparser.RobotFileParser(url='')

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

urllib.request.Request

object.

Changed in version 3.16.0a0 (unreleased): url parameter can be a

urllib.request.Request

object.

set_url(url)

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

urllib.request.Request

object.

Changed in version 3.16.0a0 (unreleased): url parameter can be a

urllib.request.Request

object.

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.

Added 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.

Added in version 3.6.

site_maps()

Returns the contents of the Sitemap parameter from robots.txt in the form of a

list()

. If there is no such parameter or the robots.txt entry for this parameter has invalid syntax, return None.

Added in version 3.8.

The following example demonstrates basic use of the

RobotFileParser

class:

>>> importurllib.robotparser>>> rp=urllib.robotparser.RobotFileParser()>>> rp.set_url("http://www.pythontest.net/robots.txt")>>> rp.read()>>> rrate=rp.request_rate("*")>>> rrate.requests1>>> rrate.seconds1>>> rp.crawl_delay("*")6>>> rp.can_fetch("*","http://www.pythontest.net/")True>>> rp.can_fetch("*","http://www.pythontest.net/no-robots-here/")FalseThe following example demonstrates use of a

urllib.request.Request

object with additional user-agent headers populated:

>>> importurllib.robotparser>>> importurllib.request>>> rp=urllib.robotparser.RobotFileParser()>>> rp.set_url(urllib.request.Request("http://www.pythontest.net/robots.txt",headers={"User-Agent":"IsraBot"}))>>> rp.read()>>> rp.can_fetch("*","http://www.pythontest.net/")True>>> rp.can_fetch("*","http://www.pythontest.net/no-robots-here/")False