TWiki Access Control
Restricting read and write access to topics and webs, by Users and groups TWiki Access Control allows you restrict access to single topics and entire webs, by individual user and by user Groups. Access control, combined with TWikiUserAuthentication, lets you easily create and manage an extremely flexible, fine-grained privilege system.
Tip: TWiki:TWiki.TWikiAccessControlSupplement on TWiki.org has additional documentation on access control.
On this page:
An Important Control Consideration
Open, freeform editing is the essence of WikiCulture - what makes TWiki different and often more effective than other collaboration tools. For that reason, it is strongly recommended that decisions to restrict read or write access to a web or a topic are made with great care - the more restrictions, the less Wiki in the mix. Experience shows that unrestricted write access works very well because:- Peer influence is enough to ensure that only relevant content is posted.
- Peer editing - the ability for anyone to rearrange all content on a page - keeps topics focused.
- In TWiki, content is transparently preserved under revision control:
- Edits can be undone by the administrator (per default a member of TWikiAdminGroup; see #ManagingGroups).
- Users are encouraged to edit and refactor (condense a long topic), since there's a safety net.
- Create broad-based Groups (for more and varied input), and...
- Avoid creating view-only Users (if you can read it, you should be able to contribute to it).
Permissions settings of the webs on this TWiki site
- A blank in the the above table may mean either the corresponding control is absent or commented out or that it has been set to a null value. The two conditions have dramatically different and possibly opposed semantics.
- TWikiGuest is the guest account - used by unauthenticated users.
- The TWiki web must not deny view to TWikiGuest; otherwise, people will not be able to register.
Authentication vs. Access Control
Authentication: Identifies who a user is based on a login procedure. See TWikiUserAuthentication. Access control: Restrict access to content based on users and groups once a user is identified.Users and Groups
Access control is based on the familiar concept of Users and Groups. Users are defined by their WikiNames. They can then be organized in unlimited combinations by inclusion in one or more user Groups. For convenience, Groups can also be included in other Groups.Managing Users
A user can create an account in TWikiRegistration. The following actions are performed:- WikiName and encrypted password are recorded using the password manager if authentication is enabled.
- A confirmation e-mail is sent to the user.
- A user home page with the WikiName of the user is created in the Main web.
- The user is added to the TWikiUsers topic.
Managing Groups
The following describes the standard TWiki support for groups. Your local TWiki may have an alternate group mapping manager installed. Check with your TWiki administrator if you are in doubt. Groups are defined by group topics located in theMain web. To create a new group, visit TWikiGroups and enter the name of the new group ending in Group into the "new group" form field. This will create a new group topic with two important settings: -
Set GROUP = < list of Users and/or Groups > -
Set ALLOWTOPICCHANGE = < list of Users and/or Groups >
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Set GROUP = Main.SomeUser, Main.OtherUser, Main.SomeGroup
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Set ALLOWTOPICCHANGE = Main.KasabianGroup
Note: TWiki has strict formatting rules. Make sure you have three spaces, an asterisk, and an extra space in front of any access control rule.
The Super Admin Group
A number of TWiki functions (for example, renaming webs) are only available to administrators. Administrators are simply users who belong to the SuperAdminGroup. This is a standard user group, the name of which is defined by {SuperAdminGroup} setting in configure. The default name of this group is theTWikiAdminGroup. The system administrator may have chosen a different name for this group if your local TWiki uses an alternate group mapping manager but for simplicity we will use the default name TWikiAdminGroup in the rest of this topic.
You can create new administrators simply by adding them to the TWikiAdminGroup topic. For example, -
Set GROUP = Main.ElizabethWindsor, Main.TonyBlair
Restricting Access
You can define who is allowed to read or write to a web or a topic. Note that some plugins may not respect access permissions.- Restricting VIEW blocks viewing and searching of content. When you restric VIEW to a topic or web, this also restricts INCLUDE and Formatted SEARCH from showing the content of the topics.
- Restricting CHANGE blocks creating new topics, changing topics or attaching files.
- Restricting RENAME prevents renaming of topics within a web.
Controlling access to a Web
You can define restrictions on who is allowed to view a TWiki-SL web. You can restrict access to certain webs to selected Users and Groups, by:- authenticating all webs and restricting selected webs: Topic access in all webs is authenticated, and selected webs have restricted access.
- authenticating and restricting selected webs only: Provide unrestricted viewing access to open webs, with authentication and restriction only on selected webs.
- You can define these settings in the WebPreferences topic, preferable towards the end of the topic:
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Set DENYWEB
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