created: 20180630194006239
modified: 20180904174030250
tags: WebServer
title: WebServer Authorization
type: text/vnd.tiddlywiki

''Authorization'' is the process of determining which resources may be accessed by a particular user. It occurs after [[authentication|WebServer Authentication]] has determined the identity of the user. TiddlyWiki's WebServer implements a simple authorization scheme which permits independent control of who has read and write access to a wiki.

The WebServer parameters [[readers|WebServer Parameter: readers]] and [[writers|WebServer Parameter: writers]] each contain a comma separated list of //principals// (which is to say, either usernames or certain special tokens) which should have read or write access respectively.

The available special tokens are:

* ''(anon)'' - indicates all anonymous users
* ''(authenticated)'' - indicates all authenticated users

!! Read-only Mode

Read-only mode is engaged when the current user is not authorized to write to the current wiki.

User interface features concerned with creating or editing content are disabled in read-only mode:

* ''clone'', ''delete'', ''new-here'' and ''new-journal-here'' tiddler toolbar buttons
* ''import'', ''manager'', ''new-tiddler'' ''new-image'' and ''new-journal'' page control buttons

The tiddler $:/status/IsReadOnly is set to `yes` when read-only mode is engaged.

!! Examples

These example use the [[credentials|WebServer Parameter: credentials]] parameter to specify the location of a file containing usernames and passwords.

In the first example, read access is permitted for the users "joe" and "mary", with write access restricted to "mary":

```
tiddlywiki mywikifolder --listen credentials=myusers.csv readers=joe,mary writers=mary
```

In the following example, read access is granted to all authenticated users, but only "mary" is granted write access:

```
tiddlywiki mywikifolder --listen credentials=myusers.csv "readers=(authenticated)" writers=mary
```