Programming Jabber

A note on error messages

Various errors can occur during user registration. They are, on the whole, fairly plain and easy to understand. But because of the way the server has been written, you might be surprised at what error message you receive in certain circumstances.

Because the required fields <username/> and <password/> are checked before looking to see whether or not there is a <register/> section in the JSM instance configuration, you will always receive a 406 “Not Acceptable” instead of a 501 “Not Implemented” if you don’t supply those fields, even if the registration mechanism has been turned off.

Likewise, if you specify a username that already exists, you will receive a 409 “Username Not Available” instead of a 501 “Not Implemented.”

Of course, if you do an IQ-get with the jabber:iq:register namespace beforehand, you will receive the “correct” error—good practice pays!