Programming Jabber

User Registration

User registration with a Jabber server specifically means the creation (or modification) of a user account for the JSM component—the component that provides the basic IM services and has a notion of users and user sessions. It takes place at the start of a connection to a Jabber server, as does user authentication, as shown in Figure 7-1.

Let’s take a look at the XML fragments involved in a typical user registration process. Example 7-1 shows the XML stream header exchange and the IQ packets in the jabber:iq:register namespace.

Example 7-1. A typical user registration process

First is the XML stream header exchange:

SEND: <?xml version='1.0'?>
      <stream:stream to='yak' xmlns='jabber:client'
                     xmlns:stream='http://etherx.jabber.org/streams'>

RECV: <?xml version='1.0'?>
      <stream:stream xmlns:stream='http://etherx.jabber.org/streams'
                     id='3B2DB1A7' xmlns='jabber:client' from='yak'>

Then the client sends a request to discover what information must be passed to the Jabber server to register a new user:

SEND: <iq type='get'>
        <query xmlns='jabber:iq:register'/>
      </iq>

RECV: <iq type='result'>
        <query xmlns='jabber:iq:register'>
          <instructions>
            Choose a username and password to register with this server.
          </instructions>
          <name/>
          <email/>
          <username/>
          <password/>
        </query>
      </iq>

The client does as asked and sends the required information, which results in a successful new user registration:

SEND: <iq type='set'> <query xmlns='jabber:iq:register'> <username>leslie</username> ...