=======
Protego
=======
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:alt: Supported Python Versions
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Protego is a pure-Python ``robots.txt`` parser with support for modern
conventions.
Install
=======
To install Protego, simply use pip:
.. code-block:: none
pip install protego
Usage
=====
>>> from protego import Protego
>>> robotstxt = """
... User-agent: *
... Disallow: /
... Allow: /about
... Allow: /account
... Disallow: /account/contact$
... Disallow: /account/*/profile
... Crawl-delay: 4
... Request-rate: 10/1m # 10 requests every 1 minute
...
... Sitemap: http://example.com/sitemap-index.xml
... Host: http://example.co.in
... """
>>> rp = Protego.parse(robotstxt)
>>> rp.can_fetch("http://example.com/profiles", "mybot")
False
>>> rp.can_fetch("http://example.com/about", "mybot")
True
>>> rp.can_fetch("http://example.com/account", "mybot")
True
>>> rp.can_fetch("http://example.com/account/myuser/profile", "mybot")
False
>>> rp.can_fetch("http://example.com/account/contact", "mybot")
False
>>> rp.crawl_delay("mybot")
4.0
>>> rp.request_rate("mybot")
RequestRate(requests=10, seconds=60, start_time=None, end_time=None)
>>> list(rp.sitemaps)
['http://example.com/sitemap-index.xml']
>>> rp.preferred_host
'http://example.co.in'
Using Protego with Requests_:
>>> from protego import Protego
>>> import requests
>>> r = requests.get("https://google.com/robots.txt")
>>> rp = Protego.parse(r.text)
>>> rp.can_fetch("https://google.com/search", "mybot")
False
>>> rp.can_fetch("https://google.com/search/about", "mybot")
True
>>> list(rp.sitemaps)
['https://www.google.com/sitemap.xml']
.. _Requests: https://3.python-requests.org/
Comparison
==========
The following table compares Protego to the most popular ``robots.txt`` parsers
implemented in Python or featuring Python bindings:
+----------------------------+---------+-----------------+--------+---------------------------+
| | Protego | RobotFileParser | Reppy | Robotexclusionrulesparser |
+============================+=========+=================+========+===========================+
| Implementation language | Python | Python | C++ | Python |
+----------------------------+---------+-----------------+--------+---------------------------+
| Reference specification | Google_ | `Martijn Koster’s 1996 draft`_ |
+----------------------------+---------+-----------------+--------+---------------------------+
| `Wildcard support`_ | ✓ | | ✓ | ✓ |
+----------------------------+---------+-----------------+--------+---------------------------+
| `Length-based precedence`_ | ✓ | | ✓ | |
+----------------------------+---------+-----------------+--------+---------------------------+
| Performance_ | | +40% | +1300% | -25% |
+----------------------------+---------+-----------------+--------+---------------------------+
.. _Google: https://developers.google.com/search/reference/robots_txt
.. _Length-based precedence: https://developers.google.com/search/reference/robots_txt#order-of-precedence-for-group-member-lines
.. _Martijn Koster’s 1996 draft: https://www.robotstxt.org/norobots-rfc.txt
.. _Performance: https://anubhavp28.github.io/gsoc-weekly-checkin-12/
.. _Wildcard support: https://developers.google.com/search/reference/robots_txt#url-matching-based-on-path-values
API Reference
=============
Class ``protego.Protego``:
Properties
----------
* ``sitemaps`` {``list_iterator``} A list of sitemaps specified in
``robots.txt``.
* ``preferred_host`` {string} Preferred host specified in ``robots.txt``.
Methods
-------
* ``parse(robotstxt_body)`` Parse ``robots.txt`` and return a new instance of
``protego.Protego``.
* ``can_fetch(url, user_agent)`` Return True if the user agent can fetch the
URL, otherwise return ``False``.
* ``crawl_delay(user_agent)`` Return the crawl delay specified for the user
agent as a float. If nothing is specified, return ``None``.
* ``request_rate(user_agent)`` Return the request rate specified for the user
agent as a named tuple ``RequestRate(requests, seconds, start_time,
end_time)``. If nothing is specified, return ``None``.