robotparser behavior on 403 (Forbidden) robot.txt files

[John Nagle]

I just discovered that the "robotparser" module interprets
a 403 ("Forbidden") status on a "robots.txt" file as meaning
"all access disallowed". That's unexpected behavior.

A major site ("http://www.aplus.net/robot.txt") has their
"robots.txt" file set up that way.

There's no real "robots.txt" standard, unfortunately.
So it's not definitively a bug.

John Nagle
SiteTruth

[=?ISO-8859-1?Q?=22Martin_v=2E_L=F6wis=22?=]

I just discovered that the "robotparser" module interprets

a 403 ("Forbidden") status on a "robots.txt" file as meaning
"all access disallowed". That's unexpected behavior.

That's specified in the "norobots RFC":

http://www.robotstxt.org/norobots-rfc.txt

- On server response indicating access restrictions (HTTP Status
Code 401 or 403) a robot should regard access to the site
completely restricted.

So if a site returns 403, we should assume that it did so
deliberately, and doesn't want to be indexed.

A major site ("http://www.aplus.net/robot.txt") has their
"robots.txt" file set up that way.

You should try "http://www.aplus.net/robots.txt" instead,
which can be accessed just fine.

Regards,
Martin