Strophe.js - How to get a group of rosters with its members?

Question

When using this Strophe command:

var iq = $iq({type: 'get'}).c('query', {xmlns: 'jabber:iq:roster'}); 
connection.sendIQ(iq)

I get this as the success callback:

<iq xmlns="jabber:client" xml:lang="pt-br" to="user01@localhost/100164477219111523302818" from="user01@localhost" type="result" id="82480785-c170-48d1-a180-bcadbff957d2:sendIQ">
  <query xmlns="jabber:iq:roster">
    <item subscription="both" jid="user02@localhost">
      <group>Roster01</group>
      <group>Roster02</group>
    </item>
    <item subscription="both" jid="admin@localhost">
      <group>Roster01</group>
      <group>Roster02</group>
    </item>
    <item subscription="both" jid="[email protected]">
      <group>Roster02</group>
    </item>
    <item subscription="both" jid="[email protected]">
      <group>Roster01</group>
    </item>
  </query>
</iq>

What I want is to know is if there's some way to get this callback grouped by the groups and its members. If there's not, how can I do it with Javascript. Examples:

• Roster 01 has admin, user02 and grupo01
• Roster 02 has admin, user02 and grupo02

I'm using ejabberd as the XMPP server and Ionic 3 with Strophe as the client.

Answer 1

I suggest to use strophejs-plugin-roster which get things easier:

// connect Strophe
connection = new Strophe.Connection(url);
connection.connect(my_jid, my_pwd, onConnect);

...

function onConnect(status) {
    if (status == Strophe.Status.CONNECTED) {
        ...

        // pass connection to roster plugin
        connection.roster.init(connection);
    }
}

Here is a function to getRoster via plugin, result is a JS array containing objects (instead of XML...):

function getRoster() {
    connection.roster.get(function (roster) {
        console.log('   >roster:', roster);
        for (var i in roster) {
            console.log('   >buddy '+i+':');
            console.log('       >'+roster[i].name+" ("+roster[i].jid+' -->'+roster[i].subscription);
            console.log('       >', roster[i].groups);
        }
        // get buddies belonging to group1 and group2 (see below)
        console.log('   >roster-group1:', getRosterGroup(roster, 'group1'));
        console.log('   >roster-group2:', getRosterGroup(roster, 'group2'));
    });
}

The function below filter buddies by group:

function getRosterGroup(roster, group) {
    var reduced = roster.reduce(function(filtered, item) {
        if (item.groups.indexOf(group)!==-1) {
            filtered.push(item);
        }
        return filtered;
    }, []);
    return reduced;
}

Here is a working Plunker: http://plnkr.co/edit/XloJABSGHZvLTp3Js2KI?p=preview