File attachment to a subwikipage triggers an internal error

[Emmanuel Blot]

When a file is attached to a sub wikipage (e.g. SandBox/Test), Trac triggers the following error message:

Attachment wiki:SandBox: Test does not exist.

It seems there is a parsing mismatch between the file path and the Wiki page separator.

Note that the file is nevertheless attached to the page, and can be accessed/retrieved/viewed without any issue, hence the 'minor' severity.

The bug shows off in Trac [4812], but it's probably older. I hope it's not a duplicate ;-)

[Tim Hatch]

This is because the url is ambiguous… is wiki/a/b for the page a/b or for the attachment b under the page a. The relevant part is the len(segments) bit under AttachmentModule.process_request in attachment.py

Maybe it should check to see if the resource constructed from the full bit exists, otherwise try it with the last bit as the filename.

[Tim Hatch]

Thinking about it a bit more, I don't think there's a "good" way to solve it without altering the url syntax. What if you have a wiki subpage and attachment of the same name? Trac couldn't just glance at the db or try it both ways because they would both be valid.

[Christian Boos]

The URL syntax for an attachment itself is unambiguous:

/attachment/wiki/(pagename/)+/filename

Now, the URL syntax for the list of attachments is unambiguous:

/attachment/wiki/(pagename/)+

as it collides with the above.

Simple solution would be to require a trailing slash in the above case (that gives a Bad request error right now, which means that this URL space is available :-) ).

[Christian Boos]

Should be fixed in r4813.