Ignore space or %20 in webapi URLs

[davidsarah]

When a wrapped URL is copied to the clipboard and then to a browser address bar, ​sometimes the copying application inserts spaces at the end of each line and the browser does not strip them. This would happen in some cases even if URLs were shorter (#882), since they can include a filename and parameters.

I think it is only spaces that get inserted, not tabs. The browser might convert these to %20 when it submits the URL, so stripping spaces should be done after %-decoding.

Note that this isn't a duplicate of #884 ('give nice error page when URL is mangled') because we need to both:

• strip spaces, in order to eliminate one of the most common forms of mangling, and
• display a nice error page for mangled URLs that we're unable to correct.

[zooko]

See related ticket #885 (automatically url-unquote caps).

[davidsarah]

Replying to zooko:

See related ticket #885 (automatically url-unquote caps).

That should be #942.

Yes, we should first %-decode and then strip spaces. I think it's sufficient to do that in uri.from_string​. (As the IURI interface doc​ says, uri.from_string is supposed to be used instead of the *URI.init_from_string factory methods, and that stipulation appears to be followed everywhere apart from test code.)

[davidsarah]

Replying to davidsarah:

(As the IURI interface doc​ says, uri.from_string is supposed to be used instead of the *URI.init_from_string factory methods, ...)

Incidentally, *URI.init_from_string are classmethods, so init_from_string shouldn't be part of the IURI interface.

[davidsarah]

#496 was a duplicate. It gave this link to a user report: ​http://allmydata.org/pipermail/tahoe-dev/2008-July/000721.html (although I disagree with the opinion in that post that only the WUI should strip spaces; I think it should be done for all webapi URLs).

As mentioned in ticket:496#comment:1, if the URL was modified then we should do a permanent redirect. This is similar to the redirect that we currently do for ?uri= (tested here, although I don't see where it's implemented).

[davidsarah]

On second thoughts, this doesn't need to be done for 1.6.1.