Wiki access control based on change/view is broken

I have set up several wiki sites where access control is important. If TWiki did not have access control, we would have to use (gag) SharePoint.

Today, I noticed for the umpteenth time that TWiki's access control is, um, suboptimal, a pain to administer.

TWiki has separate lists for read access - ALLOWWEBVIEW - and change access - ALLOWWEBCHANGE.

Since nearly everyone who is allowed to change a topic is also allowed to read it, these are redundant. The ALLOWEBCHANGE list should always be a subset of the ALLOWWEBVIEW list. When it isn't, well, it's a pain - e.g. if you leave yourself off the ALLOWWEBVIEW list you can still read the pages by going into edit, but you have to type URLs in yourself.

I recommend that a user or group being in ALLOWWEBCHANGE imply that it also has ALLOWWEBVIEW access.

If you really want some people to have edit only, but not view, access ---- well, ewe could come up with a way of representing that. But I have trouble imaging such a use.

-- Contributors: AndyGlew

Discussion

Very sadly, I have used topics where the user has write access and not view access - for logging purposes. It was decided that the edit & state log for the ISO system should not be public. So yeah, while not necessarily being hugely important, it meant that for that application, i didn't need to make a plugin, or resort to non-topic storage of info.

-- SvenDowideit - 14 Apr 2006

(Apparently the comment formatting is broken.)

Fine. So provide:

• ALLOW_TOPIC_ACCESS_READONLY
• ALLOW_TOPIC_ACCESS_READWRITE
• ALLOW_TOPIC_ACCESS_WRITEONLY

and compute

• reads_allowed = readonly + readwrite
• writes_allowed = readwrite + writeonly

This is not a functionality issue. It's a user interface issue - for the user who is the admin setting up perms.

Or, equivalently, go to an access control list

• ACCESS_LIST =
  • AndyGlew? - readwrite
  • SvenDowideit? - writeonly
  • SomeoneElse? - readonly
  • TWikiGuest? - denied

My point is that the present system violates the OAOO rule - once and only once. The user must enter a group name in multiple lists.

Heck... I just realized that a plugin could be used to fix this.

-- AndyGlew - 14 Apr 2006

TWiki's access control is suboptimal because it is confusing.

I strongly recommend looking at Role Based Access Control.

It is simple to institute and simple to administer.

-- AntonAylward - 15 Apr 2006