XMPP intro & 101

          TheCamp - July 2012
          Steffen Larsen (slarsen@braintrust.dk)



Thursday, August 2, 12
This Presentation
                         I) Intro and presentation of the protocol
                           What is it?, Usage

                           Basics and architecture

                           Examples

                         II) Advanced Topics and loose talk
                           Extensions

                           Plugins and components

                         III) XMPP 101 - Kick start and play!


Thursday, August 2, 12
About me (blah blah)

                         Studied Computer Science @ Copenhagen
                         CEO / Founder of BrainTrust ApS 2010 (Solo Ent.)
                         Prof. Software Developer for 15+ years
                           Java (JSE / JEE), C, Erlang, Ruby, Perl.

                           Open Source developer.. Tigase, Strophe-plugins, XMPPConsole etc.




Thursday, August 2, 12
My XMPP Involvement

                Member of XMPP Standard Foundation (XSF)
                Developing XMPP since 2007 (Ms.Thesis, pidgin/VOIP)
                Done XMPP design and impl. for:
                         WAOO, Nordija (Set-top-boxes and over-the-top TV and IPTV)

                         Thrane&Thrane (Maritime Satellite Communication project)

                         Danske Spil / BetWare (Game software for Bingo etc)




Thursday, August 2, 12
XMPP Intro

                         What is it?
                           XMPP - eXtensible Message and Presence
                           Protocol
                           Earlier known as Jabber - 1998
                           Real time messages system for communication
                           Routes small snipplets of XML - called stanzas



Thursday, August 2, 12
XMPP - What?
                Who uses it? Most of you use it every day as chat..
                         You? Jabber client (pidgin/adium/messenger (m$))
                         Google (gmail, google hangouts)
                         Cisco (webex)
                         Facebook (chat)
                         Even Micro$oft have XMPP gateways integrated into
                         their messaging system


Thursday, August 2, 12
XMPP Basics

                What can you do with it?
                         Everything that you can imagine (almost) :-)
                         More than just chat -- Its about presence, routing
                         and real-time communication!
                         Real time web!.. its there - push it!




Thursday, August 2, 12
XMPP Basics	
                   Basic Services and applications
                         Encryption / Authentication

                         Presence

                         Contact / Buddy lists

                         Messaging (1-1 or group chat)

                         Push Notifications (individual or publish/subscribe)

                         Service discovery and device capability advertisement

                         Geolocation and notifications

                         Voice over IP (VOIP)

                         Collaborative text editing etc.



Thursday, August 2, 12
XMPP applications
                Set-top box and OTT implementation done my self..
                Taxi service real-time: http://cabulous.com/
                Yammer.com - work in social context (ala facebook)
                status.net - DISTRIBUTED twitter (micro blog) - download and federate..
                JIVE sbs - big social site for business / whiteboarding
                Apple mobile push
                stand-alone - adium/pidgin clients etc.
                Customer Service - chat and voip - call forwarding/queue
                games: tic-tac toe / chess
                Energy Trading software




Thursday, August 2, 12
XMPP Basics
             Why XMPP? just use normal HTTP (polling), or we
             (almost) have websockets and others..)
                    XMPP is an Open Standard (like HTTP) - XSF and the council does the work
                    openly.

                    Proven tech. Almost 15 years of dev.

                    Secure - Channel encryption and strong auth.

                    Decentralized. no stand-alone silos (hello twitter and fb..)

                    Huge community

                    Extensibility!.. We have above 300 extensions to the XMPP core




Thursday, August 2, 12
XMPP Protocol	 	
                Core specifies (RFC 6120 / RFC 6121)
                         http://xmpp.org/xmpp-protocols/rfcs/
                Connect with TCP or other transport protocols (HTTP/
                websockets, specified in extensions)
                Opening a Stream tag with with streaming XML stanzas
                (<stanza>.. stanza xml .. </stream>)
                stanzas



Thursday, August 2, 12
XMPP Architecture

                XMPP can consist of many modules:
                         Servers (many through federation)

                            Plugins

                            Components (XEP-0114)

                         Clients (typically many..)

                         Proxies

                         Database, LDAP, SIP and other systems (gateways)




Thursday, August 2, 12
XMPP Architecture




Thursday, August 2, 12
XMPP Addressing & Routing

                 Standard routing through JID
                         full JID: <id>@<domain>/<resource>

                         bare JID: <id>@<domain> (autom. resource)

                         Domain routing like normal mail (smtp).




Thursday, August 2, 12
XMPP Connection Lifecycle
     To illustrate a chat client connecting
       • Initiating TCP connection to the XMPP server
       • Opening an XML <stream> for session..
       • Negotiating stream features and SASL negotiation (Simple Authentiation
       and Security Layer)

              •Auth mechanisms: PLAIN, DIGETS-MD5, SCRAM, EXTERNAL etc.
       • TLS secure layer (authentication towards the server)
       • The clients resource gets bound to the session
       • The client sends out initial presence
       • The client can now communicate (send/receive stanzas)
       • The client ends session
       • </stream> is send. And TCP connection is closed.

Thursday, August 2, 12
Communication Primitives
          Simple, we only have 3 ways:

                Stanzas (xml snipplets that flow async.)
                         Presence
                         Message
                         IQ (Information/Query)




Thursday, August 2, 12
Stanzas: Presence
                         Sets and shows the availability of the entity that is
                         connected.
                           chat

                           away

                           dnd (do not disturb)

                         Presence for the system and the subscribers of
                         the entity (e.g. buddylist)
                         Specialized Presence extension (PEP) shows what
                         music you are playing..


Thursday, August 2, 12
Stanzas: Presence
                         // initial simple presence
                         <presence/>

                         // sending away to subscribers
                         <presence>
                            <show>away</show>
                         </presence>

                         <presence>
                            <show>dnd</show>
                            <status>I am working.. </status
                         </presence>

                         // before logging off.. more realtime
                         <presence type='unavailable'/>




Thursday, August 2, 12
Stanzas: Presence
                         // direct presence

                         <presence from='juliet@example.com balcony’
                         to='romeo@example.net'/>

                         // Capabilities.. version, voip etc.

                            <presence from='romeo@example.net'>
                              <c xmlns='http://jabber.org/protocol/caps'
                                 hash='sha-1'
                                 node='http://psi-im.org'
                                 ver='q07IKJEyjvHSyhy//CH0CxmKi8w='/>
                            </presence>




Thursday, August 2, 12
Stanzas: Message
                Using it to communicate with other clients
                TO attribute
                         full JID: direct messaging to specific entity (e.g. device/computer).

                         bare JID: will route to one or more of the connected resources - depends of
                         status, presence, message type etc.

                Type attribute (chat, normal, groupchat, headline etc) -
                presentation and routing
                Body Element - the message


Thursday, August 2, 12
Stanzas: Message
                  normal message
                  <message
                         from='juliet@example.com/balcony'
                         id='ktx72v49'
                         to='romeo@example.net'
                         type='chat'
                         xml:lang='en'>
                       <body>Hi romeo where art thou?</body>
                     </message>

                  direct message
                  <message
                         from='juliet@example.com/balcony'
                         id='ktx72v50'
                         to='romeo@example.net/thecastle'
                         type='chat'
                         xml:lang='en'>
                       <body>will you come and visit?</body>
                     </message>


Thursday, August 2, 12
Stanzas: IQ

                A more request / response model. For getting
                information and query the server / entities.
                Request: GET / SET
                Response: RESULT / ERROR
                Using it for getting roster, ad-hoc command and
                statistics for server (if admin).. etc.



Thursday, August 2, 12
Stanzas: IQ
                         Example 1: User requests current roster from server

                         UC: <iq from='romeo@example.net/orchard'
                                 id='hf61v3n7'
                                 type='get'>
                               <query xmlns='jabber:iq:roster'/>
                             </iq>

                         Example 2: User receives roster from server

                         US: <iq id='hf61v3n7'
                                 to='romeo@example.net/orchard'
                                 type='result'>
                               <query xmlns='jabber:iq:roster'>
                                 <item jid='juliet@example.com'
                                        name='Juliet'
                                        subscription='both'>
                                   <group>Friends</group>
                                 </item>
                                 <item jid='benvolio@example.org'
                                        name='Benvolio'
                                        subscription='to'/>
                                 <item jid='mercutio@example.org'
                                        name='Mercutio'
                                        subscription='from'/>
                               </query>
                             </iq>

Thursday, August 2, 12
Now.. Lets have Coffee!

                While having a break and if you want to play with XMPP
                later on..
                Install java sdk
                Install apache




Thursday, August 2, 12
II) Advanced Topics
                Extensions:
                         Pub / Sub (XEP-0060)
                         BOSH (XMPP over HTTP)
                External Database and LDAP
                Internal routing and modifications via. plugins
                Components



Thursday, August 2, 12
XMPP Extensions
                XSF defines a set of XMPP Extension Protocols (XEPs).
                > 300 at the moment
                           http://xmpp.org/xmpp-protocols/xmpp-extensions/.

                Jingle (Gtalk), MUC (hangouts), file transfer, etc..
                publish/subscribe
                We will concentrate on:
                         publish / subscribe & BOSH (XMPP on the web)


Thursday, August 2, 12
Publish / Subscribe
          (XEP-0060)

                Pub/Sub embbeds in IQ stanza
                Put JIDs into groups and push out messages to many
                subscribers!
                Let people subscribe/unsubscribe for data on a node
                Setup roles and affiliates..




Thursday, August 2, 12
Publish / Subscribe
          (XEP-0060)
                         <iq type='set'
                             from='hamlet@denmark.lit/blogbot'
                             to='pubsub.shakespeare.lit'
                             id='pub1'>
                           <pubsub xmlns='http://jabber.org/protocol/pubsub'>
                             <publish node='princely_musings'>
                               <item>
                                 <entry xmlns='http://www.w3.org/2005/Atom'>
                                   <title>Soliloquy</title>
                                   <summary>
                         To be, or not to be: that is the question:
                         Whether 'tis nobler in the mind to suffer
                         The slings and arrows of outrageous fortune,
                         Or to take arms against a sea of troubles,
                         And by opposing end them?
                                   </summary>
                                   <link rel='alternate' type='text/html'
                                         href='http://denmark.lit/2003/12/13/atom03'/>
                                   <id>tag:denmark.lit,2003:entry-32397</id>
                                   <published>2003-12-13T18:30:02Z</published>
                                   <updated>2003-12-13T18:30:02Z</updated>
                                 </entry>
                               </item>
                             </publish>
                           </pubsub>
                         </iq>

Thursday, August 2, 12
Publish / Subscribe
          (XEP-0060)
      Subscribers receives published data
                   <message from='pubsub.shakespeare.lit' to='francisco@denmark.lit' id='foo'>
                     <event xmlns='http://jabber.org/protocol/pubsub#event'>
                       <items node='princely_musings'>
                         <item id='ae890ac52d0df67ed7cfdf51b644e901'>
                           [ ... ENTRY ... ]
                         </item>
                       </items>
                     </event>
                   </message>

                   <message from='pubsub.shakespeare.lit' to='bernardo@denmark.lit' id='bar'>
                     <event xmlns='http://jabber.org/protocol/pubsub#event'>
                       <items node='princely_musings'>
                         <item id='ae890ac52d0df67ed7cfdf51b644e901'>
                           [ ... ENTRY ... ]
                         </item>
                       </items>
                     </event>
                   </message>



Thursday, August 2, 12
BOSH (XEP-0124)
                   Bidrectional streams Over Synchronous Http
                   (BOSH)
                         HTTPs api are great - Polling sucks.
                         Long Polling. XMPP embedded into HTTP
                         why? simple, known tech. use compress etc.
                         Small problem: cross origin policy (diff. ports)
                           default BOSH port 5280 - HTTP 80


Thursday, August 2, 12
BOSH
         HTTP hold the connection until there is something
                            to send




Thursday, August 2, 12
BOSH - XMPP over HTTP
                     POST /webclient HTTP/1.1
                     Host: httpcm.example.com
                     Accept-Encoding: gzip, deflate
                     Content-Type: text/xml; charset=utf-8
                     Content-Length: 188

                     <body rid='1249243562'
                           sid='SomeSID'
                           xmlns='http://jabber.org/protocol/httpbind'>

                         <message to='contact@example.com'
                                  xmlns='jabber:client'>
                           <body>Good morning!</body>
                         </message>

                     </body>


Thursday, August 2, 12
BOSH - XMPP over HTTP

      • No data - empty body tag from server
      • Works through header setup and timeouts

                         HTTP/1.1 200 OK
                         Content-Type: text/xml; charset=utf-8
                         Content-Length: 64

                         <body xmlns='http://jabber.org/protocol/
                         httpbind'/>




Thursday, August 2, 12
Plugins & Components




Thursday, August 2, 12
Some advanced features
                Normal client “bots” easy to do, but have limitations
                To incorporate your own business logic you need some
                more..
                To make advanced features on the server side
                         Server Plugins
                         Components
                External Auth.. either plain db, ldap or others.


Thursday, August 2, 12
Server Plugins

                Located on the server
                Change routing strategy
                Filter packages / Drop packages
                Do statistics etc.
                Bound to the server implementation - not portable
                Can hog mem/cpu from the server. Its embedded!.
                (take care)

Thursday, August 2, 12
Components (XEP-0114)
                Components conn. to the server or vice versa (normal
                TCP)
                Handshakes and authenticates (trusted by server)
                Portable
                Can be run externally with code implemented in almost
                every language.




Thursday, August 2, 12
Components (XEP-0114)

                Acts almost like a “normal” client. e.g. JID
                (comp@braintrust.dk)...
                Can act and interact on the whole domain.. not multiple
                Can alter the to/from fields...
                Can’t drop/filter packages for every domain.




Thursday, August 2, 12
Break!! ...
          Next developing XMPP 101
                    Lets have some hands-on experience.
                    Install Java (version 6 and up is fine)
                    Install Apache web server
                    Get XMPP server up and running
                    Play..




Thursday, August 2, 12
XMPP 101 - playtime!

                Install your very own XMPP server!
                Setup Apache or other httpd / proxy
                Download Strophe and setup examples..
                Play!




Thursday, August 2, 12
Developing XMPP
      Learned so far:
                XMPP can run on every device, on mobile, on the web
                on
                XMPP makes a bridge and makes the device present
                and available to communicate with other entities..
                Client frameworks for almost every language
                         Java, Javascript, C / C++, Erlang, C#, Python, Ruby, Perl etc.

                We will focus on the web (client side) and hence do
                javascript

Thursday, August 2, 12
XMPP Kick Start!
    But first! to make it work, we need a server

                  • Choose your favorite XMPP server!
                  • The list is long:  http://xmpp.org/xmpp-software/servers/


                  • Be ware of the license. Some are
                         commercial/gpl/gpl3/apache etc.




Thursday, August 2, 12
XMPP Servers

                Administrators would look for monitoring and tools.
                Extensions.. E.g. some can pub/sub, some can’t. So
                choose from your specific application.
                Clustering or not? What is your demand? 5k users?
                500k users?




Thursday, August 2, 12
My recommendations		 	
                         Ejabberd 2.1.11 (http://www.ejabberd.im/)
                           cool features dist. out-of-the-box. Thanks
                           erlang!
                           high load factor
                         Tigase 5.1.x (linux, mac etc. *NIX.)
                           very flexible. Code injection on the fly. Groovy /
                           Java. Easy to understand
                           Many extensions available
                           Good monitoring tools!
Thursday, August 2, 12
Windows users?...		

                If you can’t run shell scripts etc.
                Openfire might be easier:
                http://goo.gl/9HYeb
                Should be easy to setup.. I’ll help later. No worry. :-)




Thursday, August 2, 12
Tigase XMPP server	
                Install Java if you dont have it!

                Install tigase:

                         download http://goo.gl/jYNFD

                         run the downloaded jar file: java -jar tigase...jar

                Setup easy. in step 7, choose only base, extras and derby database. in the other
                steps just press next!

                cd {TIGASE_HOME} (where you installed it)

                Start: ./scripts/tigase.sh start etc/tigase.conf

                Stop: ./scripts/tigase.sh stop

                add a new user to the server (use a client: PSI, Adium , Pidgin etc)

Thursday, August 2, 12
Proxy setup

                         because of same origin policy.. if you have a
                         CORS enabled browser, this is not needed
                         http://httpd.apache.org/download.cgi
                         proxy_module should be enabled.
                         in httpd.conf (proxy port 80 to port 5280)
                           ProxyPass /http-bind/ http://localhost:5280/http-bind/




Thursday, August 2, 12
XMPP libraries..	

                There a many!   http://xmpp.org/xmpp-software/libraries/

                Native or BOSH (XMPP over HTTP)
                We focus on BOSH.. lets enable real-time push on the
                web.
                Strophe.js!




Thursday, August 2, 12
Strophe Install
                Download here: http://goo.gl/5btM2
                unzip / untar the downloaded package into your
                Apache web folder (on mac: Library/WebServer/
                Documents).
                You can change the folder in the httpd.conf if you want.
                change in examples/echobot.js :
                         var BOSH_SERVICE = '/http-bind/';

                Ready to run!. if server is running, fire up your browser
                and use the user created just before when logging in.

Thursday, August 2, 12
Strophe
                Pure javascript XMPP library (integrated with jquery)
                Using BOSH as connection type
                Simple manipulations with Stanzas
                Build everything like DOM
                Light and Event driven..
                Here is my example: http://localhost/webchat



Thursday, August 2, 12
Strophe

        Make connection on the BOSH URL defined in
                      apache proxy:
                         var conn = new Strophe.connection(“localhost/http-bind”);


  Connect with JID (full/bare) and make cb function:
                         conn.connect(JID, password, callbackfn);




Thursday, August 2, 12
Strophe

 Strophe have static status to check on the connection

    function onConnection () {
      if (status == Strophe.Status.CONNECTED) {
             // do something!
         } else if (status ...
         ..
    }

Thursday, August 2, 12
Strophe - Sending /
          Receiving
             conn.send(xml);....

             conn.addHandler(on_message,
                null, “message”, “chat”);
             on_message(message) {
                console.log(“Hi there: “ + message);
                return true;
             }

Thursday, August 2, 12
Strophe..

       1. function onMessage(msg) {
       2.     $(msg).find("message[type='chat'][from]:has(body)")
       3.         .each(function () {
       4.              var body = $(this).find("body:first").text();
       5.              var from = $(this).attr("from");
       6.
       7.              log('ECHOBOT: I got a message from ' + from + ': ' + body);
       8.
       9.              var reply = $msg({to: from, type: "chat"})
       10.                  .c("body")
       11.                  .t(body);
       12.              connection.send(reply.tree());
       13.
       14.              log('ECHOBOT: I sent ' + from + ': ' + body);
       15.         });
       16.}




Thursday, August 2, 12
Strophe - Stanzas..

                Strophe have convenience methods:
                $pres(attributes..);
                $msg(attributes..);
                $iq(attributes..);




Thursday, August 2, 12
Strophe - Stanzas
              Sending initial presence:
                         $pres();
         Building a message stanza:

                         $msg({to: ‘zooldk@gmail.com’, ‘type’ :
                            ‘chat’}).c(‘body’).t(‘Hello zool!’);




Thursday, August 2, 12
</stream>..the end..
                         Contact me at
                            Email/XMPP: slarsen@braintrust.dk / zooldk@gmail.com

                            LinkedIn: http://dk.linkedin.com/in/zooldk

                            Illustrations by Adrian Teh (Too lazy to draw my self..)

                            XMPP standard foundation: http://xmpp.org

                         Links
                         Server list: http://xmpp.org/xmpp-software/servers/

                         Client list: http://xmpp.org/xmpp-software/clients/

                         Libraries: http://xmpp.org/xmpp-software/libraries/

                         Strophe:

Thursday, August 2, 12

XMPP Intro - The camp2012

  • 1.
    XMPP intro &101 TheCamp - July 2012 Steffen Larsen (slarsen@braintrust.dk) Thursday, August 2, 12
  • 2.
    This Presentation I) Intro and presentation of the protocol What is it?, Usage Basics and architecture Examples II) Advanced Topics and loose talk Extensions Plugins and components III) XMPP 101 - Kick start and play! Thursday, August 2, 12
  • 3.
    About me (blahblah) Studied Computer Science @ Copenhagen CEO / Founder of BrainTrust ApS 2010 (Solo Ent.) Prof. Software Developer for 15+ years Java (JSE / JEE), C, Erlang, Ruby, Perl. Open Source developer.. Tigase, Strophe-plugins, XMPPConsole etc. Thursday, August 2, 12
  • 4.
    My XMPP Involvement Member of XMPP Standard Foundation (XSF) Developing XMPP since 2007 (Ms.Thesis, pidgin/VOIP) Done XMPP design and impl. for: WAOO, Nordija (Set-top-boxes and over-the-top TV and IPTV) Thrane&Thrane (Maritime Satellite Communication project) Danske Spil / BetWare (Game software for Bingo etc) Thursday, August 2, 12
  • 5.
    XMPP Intro What is it? XMPP - eXtensible Message and Presence Protocol Earlier known as Jabber - 1998 Real time messages system for communication Routes small snipplets of XML - called stanzas Thursday, August 2, 12
  • 6.
    XMPP - What? Who uses it? Most of you use it every day as chat.. You? Jabber client (pidgin/adium/messenger (m$)) Google (gmail, google hangouts) Cisco (webex) Facebook (chat) Even Micro$oft have XMPP gateways integrated into their messaging system Thursday, August 2, 12
  • 7.
    XMPP Basics What can you do with it? Everything that you can imagine (almost) :-) More than just chat -- Its about presence, routing and real-time communication! Real time web!.. its there - push it! Thursday, August 2, 12
  • 8.
    XMPP Basics Basic Services and applications Encryption / Authentication Presence Contact / Buddy lists Messaging (1-1 or group chat) Push Notifications (individual or publish/subscribe) Service discovery and device capability advertisement Geolocation and notifications Voice over IP (VOIP) Collaborative text editing etc. Thursday, August 2, 12
  • 9.
    XMPP applications Set-top box and OTT implementation done my self.. Taxi service real-time: http://cabulous.com/ Yammer.com - work in social context (ala facebook) status.net - DISTRIBUTED twitter (micro blog) - download and federate.. JIVE sbs - big social site for business / whiteboarding Apple mobile push stand-alone - adium/pidgin clients etc. Customer Service - chat and voip - call forwarding/queue games: tic-tac toe / chess Energy Trading software Thursday, August 2, 12
  • 10.
    XMPP Basics Why XMPP? just use normal HTTP (polling), or we (almost) have websockets and others..) XMPP is an Open Standard (like HTTP) - XSF and the council does the work openly. Proven tech. Almost 15 years of dev. Secure - Channel encryption and strong auth. Decentralized. no stand-alone silos (hello twitter and fb..) Huge community Extensibility!.. We have above 300 extensions to the XMPP core Thursday, August 2, 12
  • 11.
    XMPP Protocol Core specifies (RFC 6120 / RFC 6121) http://xmpp.org/xmpp-protocols/rfcs/ Connect with TCP or other transport protocols (HTTP/ websockets, specified in extensions) Opening a Stream tag with with streaming XML stanzas (<stanza>.. stanza xml .. </stream>) stanzas Thursday, August 2, 12
  • 12.
    XMPP Architecture XMPP can consist of many modules: Servers (many through federation) Plugins Components (XEP-0114) Clients (typically many..) Proxies Database, LDAP, SIP and other systems (gateways) Thursday, August 2, 12
  • 13.
  • 14.
    XMPP Addressing &Routing Standard routing through JID full JID: <id>@<domain>/<resource> bare JID: <id>@<domain> (autom. resource) Domain routing like normal mail (smtp). Thursday, August 2, 12
  • 15.
    XMPP Connection Lifecycle To illustrate a chat client connecting • Initiating TCP connection to the XMPP server • Opening an XML <stream> for session.. • Negotiating stream features and SASL negotiation (Simple Authentiation and Security Layer) •Auth mechanisms: PLAIN, DIGETS-MD5, SCRAM, EXTERNAL etc. • TLS secure layer (authentication towards the server) • The clients resource gets bound to the session • The client sends out initial presence • The client can now communicate (send/receive stanzas) • The client ends session • </stream> is send. And TCP connection is closed. Thursday, August 2, 12
  • 16.
    Communication Primitives Simple, we only have 3 ways: Stanzas (xml snipplets that flow async.) Presence Message IQ (Information/Query) Thursday, August 2, 12
  • 17.
    Stanzas: Presence Sets and shows the availability of the entity that is connected. chat away dnd (do not disturb) Presence for the system and the subscribers of the entity (e.g. buddylist) Specialized Presence extension (PEP) shows what music you are playing.. Thursday, August 2, 12
  • 18.
    Stanzas: Presence // initial simple presence <presence/> // sending away to subscribers <presence> <show>away</show> </presence> <presence> <show>dnd</show> <status>I am working.. </status </presence> // before logging off.. more realtime <presence type='unavailable'/> Thursday, August 2, 12
  • 19.
    Stanzas: Presence // direct presence <presence from='juliet@example.com balcony’ to='romeo@example.net'/> // Capabilities.. version, voip etc. <presence from='romeo@example.net'> <c xmlns='http://jabber.org/protocol/caps' hash='sha-1' node='http://psi-im.org' ver='q07IKJEyjvHSyhy//CH0CxmKi8w='/> </presence> Thursday, August 2, 12
  • 20.
    Stanzas: Message Using it to communicate with other clients TO attribute full JID: direct messaging to specific entity (e.g. device/computer). bare JID: will route to one or more of the connected resources - depends of status, presence, message type etc. Type attribute (chat, normal, groupchat, headline etc) - presentation and routing Body Element - the message Thursday, August 2, 12
  • 21.
    Stanzas: Message normal message <message from='juliet@example.com/balcony' id='ktx72v49' to='romeo@example.net' type='chat' xml:lang='en'> <body>Hi romeo where art thou?</body> </message> direct message <message from='juliet@example.com/balcony' id='ktx72v50' to='romeo@example.net/thecastle' type='chat' xml:lang='en'> <body>will you come and visit?</body> </message> Thursday, August 2, 12
  • 22.
    Stanzas: IQ A more request / response model. For getting information and query the server / entities. Request: GET / SET Response: RESULT / ERROR Using it for getting roster, ad-hoc command and statistics for server (if admin).. etc. Thursday, August 2, 12
  • 23.
    Stanzas: IQ Example 1: User requests current roster from server UC: <iq from='romeo@example.net/orchard' id='hf61v3n7' type='get'> <query xmlns='jabber:iq:roster'/> </iq> Example 2: User receives roster from server US: <iq id='hf61v3n7' to='romeo@example.net/orchard' type='result'> <query xmlns='jabber:iq:roster'> <item jid='juliet@example.com' name='Juliet' subscription='both'> <group>Friends</group> </item> <item jid='benvolio@example.org' name='Benvolio' subscription='to'/> <item jid='mercutio@example.org' name='Mercutio' subscription='from'/> </query> </iq> Thursday, August 2, 12
  • 24.
    Now.. Lets haveCoffee! While having a break and if you want to play with XMPP later on.. Install java sdk Install apache Thursday, August 2, 12
  • 25.
    II) Advanced Topics Extensions: Pub / Sub (XEP-0060) BOSH (XMPP over HTTP) External Database and LDAP Internal routing and modifications via. plugins Components Thursday, August 2, 12
  • 26.
    XMPP Extensions XSF defines a set of XMPP Extension Protocols (XEPs). > 300 at the moment http://xmpp.org/xmpp-protocols/xmpp-extensions/. Jingle (Gtalk), MUC (hangouts), file transfer, etc.. publish/subscribe We will concentrate on: publish / subscribe & BOSH (XMPP on the web) Thursday, August 2, 12
  • 27.
    Publish / Subscribe (XEP-0060) Pub/Sub embbeds in IQ stanza Put JIDs into groups and push out messages to many subscribers! Let people subscribe/unsubscribe for data on a node Setup roles and affiliates.. Thursday, August 2, 12
  • 28.
    Publish / Subscribe (XEP-0060) <iq type='set'     from='hamlet@denmark.lit/blogbot'     to='pubsub.shakespeare.lit'     id='pub1'>   <pubsub xmlns='http://jabber.org/protocol/pubsub'>     <publish node='princely_musings'>       <item>         <entry xmlns='http://www.w3.org/2005/Atom'>           <title>Soliloquy</title>           <summary> To be, or not to be: that is the question: Whether 'tis nobler in the mind to suffer The slings and arrows of outrageous fortune, Or to take arms against a sea of troubles, And by opposing end them?           </summary>           <link rel='alternate' type='text/html'                 href='http://denmark.lit/2003/12/13/atom03'/>           <id>tag:denmark.lit,2003:entry-32397</id>           <published>2003-12-13T18:30:02Z</published>           <updated>2003-12-13T18:30:02Z</updated>         </entry>       </item>     </publish>   </pubsub> </iq> Thursday, August 2, 12
  • 29.
    Publish / Subscribe (XEP-0060) Subscribers receives published data <message from='pubsub.shakespeare.lit' to='francisco@denmark.lit' id='foo'>   <event xmlns='http://jabber.org/protocol/pubsub#event'>     <items node='princely_musings'>       <item id='ae890ac52d0df67ed7cfdf51b644e901'>         [ ... ENTRY ... ]       </item>     </items>   </event> </message> <message from='pubsub.shakespeare.lit' to='bernardo@denmark.lit' id='bar'>   <event xmlns='http://jabber.org/protocol/pubsub#event'>     <items node='princely_musings'>       <item id='ae890ac52d0df67ed7cfdf51b644e901'>         [ ... ENTRY ... ]       </item>     </items>   </event> </message> Thursday, August 2, 12
  • 30.
    BOSH (XEP-0124) Bidrectional streams Over Synchronous Http (BOSH) HTTPs api are great - Polling sucks. Long Polling. XMPP embedded into HTTP why? simple, known tech. use compress etc. Small problem: cross origin policy (diff. ports) default BOSH port 5280 - HTTP 80 Thursday, August 2, 12
  • 31.
    BOSH HTTP hold the connection until there is something to send Thursday, August 2, 12
  • 32.
    BOSH - XMPPover HTTP POST /webclient HTTP/1.1 Host: httpcm.example.com Accept-Encoding: gzip, deflate Content-Type: text/xml; charset=utf-8 Content-Length: 188 <body rid='1249243562'       sid='SomeSID'       xmlns='http://jabber.org/protocol/httpbind'>   <message to='contact@example.com'            xmlns='jabber:client'>     <body>Good morning!</body>   </message> </body> Thursday, August 2, 12
  • 33.
    BOSH - XMPPover HTTP • No data - empty body tag from server • Works through header setup and timeouts HTTP/1.1 200 OK Content-Type: text/xml; charset=utf-8 Content-Length: 64 <body xmlns='http://jabber.org/protocol/ httpbind'/> Thursday, August 2, 12
  • 34.
  • 35.
    Some advanced features Normal client “bots” easy to do, but have limitations To incorporate your own business logic you need some more.. To make advanced features on the server side Server Plugins Components External Auth.. either plain db, ldap or others. Thursday, August 2, 12
  • 36.
    Server Plugins Located on the server Change routing strategy Filter packages / Drop packages Do statistics etc. Bound to the server implementation - not portable Can hog mem/cpu from the server. Its embedded!. (take care) Thursday, August 2, 12
  • 37.
    Components (XEP-0114) Components conn. to the server or vice versa (normal TCP) Handshakes and authenticates (trusted by server) Portable Can be run externally with code implemented in almost every language. Thursday, August 2, 12
  • 38.
    Components (XEP-0114) Acts almost like a “normal” client. e.g. JID (comp@braintrust.dk)... Can act and interact on the whole domain.. not multiple Can alter the to/from fields... Can’t drop/filter packages for every domain. Thursday, August 2, 12
  • 39.
    Break!! ... Next developing XMPP 101 Lets have some hands-on experience. Install Java (version 6 and up is fine) Install Apache web server Get XMPP server up and running Play.. Thursday, August 2, 12
  • 40.
    XMPP 101 -playtime! Install your very own XMPP server! Setup Apache or other httpd / proxy Download Strophe and setup examples.. Play! Thursday, August 2, 12
  • 41.
    Developing XMPP Learned so far: XMPP can run on every device, on mobile, on the web on XMPP makes a bridge and makes the device present and available to communicate with other entities.. Client frameworks for almost every language Java, Javascript, C / C++, Erlang, C#, Python, Ruby, Perl etc. We will focus on the web (client side) and hence do javascript Thursday, August 2, 12
  • 42.
    XMPP Kick Start! But first! to make it work, we need a server • Choose your favorite XMPP server! • The list is long: http://xmpp.org/xmpp-software/servers/ • Be ware of the license. Some are commercial/gpl/gpl3/apache etc. Thursday, August 2, 12
  • 43.
    XMPP Servers Administrators would look for monitoring and tools. Extensions.. E.g. some can pub/sub, some can’t. So choose from your specific application. Clustering or not? What is your demand? 5k users? 500k users? Thursday, August 2, 12
  • 44.
    My recommendations Ejabberd 2.1.11 (http://www.ejabberd.im/) cool features dist. out-of-the-box. Thanks erlang! high load factor Tigase 5.1.x (linux, mac etc. *NIX.) very flexible. Code injection on the fly. Groovy / Java. Easy to understand Many extensions available Good monitoring tools! Thursday, August 2, 12
  • 45.
    Windows users?... If you can’t run shell scripts etc. Openfire might be easier: http://goo.gl/9HYeb Should be easy to setup.. I’ll help later. No worry. :-) Thursday, August 2, 12
  • 46.
    Tigase XMPP server Install Java if you dont have it! Install tigase: download http://goo.gl/jYNFD run the downloaded jar file: java -jar tigase...jar Setup easy. in step 7, choose only base, extras and derby database. in the other steps just press next! cd {TIGASE_HOME} (where you installed it) Start: ./scripts/tigase.sh start etc/tigase.conf Stop: ./scripts/tigase.sh stop add a new user to the server (use a client: PSI, Adium , Pidgin etc) Thursday, August 2, 12
  • 47.
    Proxy setup because of same origin policy.. if you have a CORS enabled browser, this is not needed http://httpd.apache.org/download.cgi proxy_module should be enabled. in httpd.conf (proxy port 80 to port 5280) ProxyPass /http-bind/ http://localhost:5280/http-bind/ Thursday, August 2, 12
  • 48.
    XMPP libraries.. There a many! http://xmpp.org/xmpp-software/libraries/ Native or BOSH (XMPP over HTTP) We focus on BOSH.. lets enable real-time push on the web. Strophe.js! Thursday, August 2, 12
  • 49.
    Strophe Install Download here: http://goo.gl/5btM2 unzip / untar the downloaded package into your Apache web folder (on mac: Library/WebServer/ Documents). You can change the folder in the httpd.conf if you want. change in examples/echobot.js : var BOSH_SERVICE = '/http-bind/'; Ready to run!. if server is running, fire up your browser and use the user created just before when logging in. Thursday, August 2, 12
  • 50.
    Strophe Pure javascript XMPP library (integrated with jquery) Using BOSH as connection type Simple manipulations with Stanzas Build everything like DOM Light and Event driven.. Here is my example: http://localhost/webchat Thursday, August 2, 12
  • 51.
    Strophe Make connection on the BOSH URL defined in apache proxy: var conn = new Strophe.connection(“localhost/http-bind”); Connect with JID (full/bare) and make cb function: conn.connect(JID, password, callbackfn); Thursday, August 2, 12
  • 52.
    Strophe Strophe havestatic status to check on the connection function onConnection () { if (status == Strophe.Status.CONNECTED) { // do something! } else if (status ... .. } Thursday, August 2, 12
  • 53.
    Strophe - Sending/ Receiving conn.send(xml);.... conn.addHandler(on_message, null, “message”, “chat”); on_message(message) { console.log(“Hi there: “ + message); return true; } Thursday, August 2, 12
  • 54.
    Strophe.. 1. function onMessage(msg) { 2. $(msg).find("message[type='chat'][from]:has(body)") 3. .each(function () { 4. var body = $(this).find("body:first").text(); 5. var from = $(this).attr("from"); 6. 7. log('ECHOBOT: I got a message from ' + from + ': ' + body); 8. 9. var reply = $msg({to: from, type: "chat"}) 10. .c("body") 11. .t(body); 12. connection.send(reply.tree()); 13. 14. log('ECHOBOT: I sent ' + from + ': ' + body); 15. }); 16.} Thursday, August 2, 12
  • 55.
    Strophe - Stanzas.. Strophe have convenience methods: $pres(attributes..); $msg(attributes..); $iq(attributes..); Thursday, August 2, 12
  • 56.
    Strophe - Stanzas Sending initial presence: $pres(); Building a message stanza: $msg({to: ‘zooldk@gmail.com’, ‘type’ : ‘chat’}).c(‘body’).t(‘Hello zool!’); Thursday, August 2, 12
  • 57.
    </stream>..the end.. Contact me at Email/XMPP: slarsen@braintrust.dk / zooldk@gmail.com LinkedIn: http://dk.linkedin.com/in/zooldk Illustrations by Adrian Teh (Too lazy to draw my self..) XMPP standard foundation: http://xmpp.org Links Server list: http://xmpp.org/xmpp-software/servers/ Client list: http://xmpp.org/xmpp-software/clients/ Libraries: http://xmpp.org/xmpp-software/libraries/ Strophe: Thursday, August 2, 12