Peter Robinett [email protected] for DUSE VI, 2010-06-30

Peter Robinett Peter@Bubblefoundry.Com for DUSE VI, 2010-06-30

"' L-* Fr#1'w3r/ f3r F72 #2& Pr3)6

W,3 #1 I?

● Background in web programming with interpreted languages (PHP, Python, Javascript, etc)

● Likes long walks on the beaches

● Lift + Scala programmer for one year

● Loves both cats AND dogs

● Lift committer for approx. 6 months BUT only has minor commit to lift-flot to my name

● Likes fine wine and smooth jazz

● BUT active on mailing list and wiki

● Isn't very good at making funny bullet points

W,#6 . L-*?

Lift is an expressive and elegant framework for writing web applications.

Lift stresses the importance of security, maintainability, scalability and performance, while allowing for high levels of developer productivity.

Lift is inspired by Seaside, Rails, Django, Wicket, and beyond.

W,9 F72?

class AskName extends CometActor { def render = ajaxForm(

What is your username?

++ text("",name => answer(name.trim)) ++ ) } class Chat extends CometActor with CometListener { private var userName = "" private var chats: List[ChatLine] = Nil private lazy val infoId = uniqueId + "_info" C31'6 private lazy val infoIn = uniqueId + "_in" private lazy val inputArea = findKids(defaultXml, "chat", "input") private lazy val bodyArea = findKids(defaultXml, "chat", "body") private lazy val singleLine = deepFindKids(bodyArea, "chat", "list") // handle an update to the chat lists // by diffing the lists and then sending a partial update // to the browser override def lowPriority = { case ChatServerUpdate(value) => val update = (value -- chats).reverse.map(b => AppendHtml(infoId, line(b))) partialUpdate(update) chats = value } // render the input area by binding the // appropriate dynamically generated code to the // view supplied by the template override lazy val fixedRender: Box[NodeSeq] = ajaxForm(After(100, SetValueAndFocus(infoIn, "")), bind("chat", inputArea, "input" -> text("", sendMessage _, "id" -> infoIn))) // send a message to the chat server private def sendMessage(msg: String) = ChatServer ! ChatServerMsg(userName, msg.trim) // display a line private def line(c: ChatLine) = bind("list", singleLine, "when" -> hourFormat(c.when), "who" -> c.user, "msg" -> c.msg) // display a list of chats private def displayList(in: NodeSeq): NodeSeq = chats.reverse.flatMap(line) // render the whole list of chats override def render = bind("chat", bodyArea, "name" -> userName, AttrBindParam("id", Text(infoId), "id"), "list" -> displayList _) // setup the component override def localSetup { askForName super.localSetup } // register as a listener def registerWith = ChatServer // ask for the user's name private def askForName { if (userName.length == 0) { ask(new AskName, "what's your username") { case s: String if (s.trim.length > 2) => userName = s.trim reRender(true)

case _ => askForName reRender(false) } } } } "' C31172-69

W,9 Pr3)6#b0'?

W,9 S%#0#?

!00 6,' 23r1#0 r'$325, p075...

!%63r5 Allows great AJAX, Comet support. The time is . class Clock extends CometActor { override def defaultPrefix = Full("clock") // schedule a ping every 10 seconds so we redraw ActorPing.schedule(this, Tick, 10 seconds) private lazy val spanId = uniqueId+"_timespan" def render = { bind("time" -> timeSpan) } def timeSpan = ({timeNow}) override def lowPriority = { case Tick => partialUpdate(SetHtml(spanId, Text(timeNow.toString))) ActorPing.schedule(this, Tick, 10 seconds) } } case object Tick

BUT, there were issues with th e EFPL library so David wrote LiftActor. This is actually a proof of Scala's strength. XHTML Pr3%(5-2+ Template: Hi . It's now .

Snippet:

import java.util.Date import scala.xml.{NodeSeq, Text} import net.liftweb.util.Helpers.bind object DuSE { def sayHello(xhtml: NodeSeq): NodeSeq = { User.currentUser.map(user => { bind(“DuSE”, xhtml, “name” -> Text(user.shortName), “datetime” -> Text((new Date).toString) ) }) openOr

You didn't log in!

} } R376-2+

Routing is done via SiteMap...

val entries = Menu(Loc(“App Page”, “app” :: “view” :: Nil, “App Page”) :: Nil LiftRules.setSiteMap(SiteMap(entries :_*))

... and redirects with partial functions!

LiftRules.statefulRewrite.prepend({ case RewriteRequest(ParsePath("app" :: appID :: "index" :: Nil, _, _,_), GetRequest, _) => RewriteResponse("app":: "view" :: Nil, Map("appID" -> appID) })

Regex Free!

W,#6 . L-* +33& #6?

● Comet, also AJAX

● X(HT)ML processing

● JSON

● REST

● As much or as little as you want done for you

● Secure

● Fast execution, fast development (IF you already know Lift)

● Great code:functionality ratio W,#6 . L-* b#& #6?

● High learning curve

● Stateless request/response cycle (but is possible)

● View-first, not MVC

● I.E. Does some things differently

● Statefulness can lead to lots of stuff in memory if you're not careful

H3w 63 +'6 L-*'&?

By Markus Lütkemeyer http://flickr.com/photos/helico/2245863081/ ! D-+r(5-32 32 V'r5-325

By Alan Sung http://flickr.com/photos/clsung/310886130/ ● 2.0-SNAPSHOT is quite stable

● RCs are really stable, only important bug ﬁxes are added. We're at 2.0-RC2.

● Milestones are very stable. Last one was 2.0-M6.

● If you have crazy rules requiring that you MUST use 'ofﬁcial' releases, wait a week for 2.0.

● Moral of the story: DON'T use 1.x.

● PS Scala 2.8 support in 280_port_refresh, should see 3.0-SNAPSHOT after the 2.0 release.

J3-2 6,' G33+0' Gr37p

http://groups.google.com/group/liftweb

R'#& 6,' G'66-2+ S6#r6'& G7-&' http://www.liftweb.net/docs/getting_started.html

S/-1 6,' W-/- http://www.assembla.com/wiki/show/liftweb/

C,'%/376 6,' S%#0#&3%5 http://scala-tools.org/mvnsites-snapshots/liftweb/

C032' 6,' %3&'

http://github.com/lift/lift *

* Yep, since last night we've been using the new GitHub organizations feature. We're cutting edge like that.

U5' #2 !r%,'6:'

● lift-archetype-basic

● lift-archetype-blank

● lift-archetype-jpa-basic

● lift-archetyp-jpa-blank-single

● lift-archetyp-jpa-blank

● lift-archetyp-sbt

5b6 simple-build-tool is THE way to do Scala projects.

See http://www.assembla.com/wiki/show/liftweb/Using_SBT

git clone git://github.com/dpp/lift_sbt_prototype.git

Then cd into lift_sbt_prototype and type: sbt

At the sbt prompt, type: update

Then: jetty-run

Point your browser to http://localhost:8080/ Mads Hartmann is working on sbt processors for Google Summer of Code. It should be awesome. M#v'2 http://www.assembla.com/wiki/show/liftweb/Using_Maven

mvn archetype:generate \ -DarchetypeGroupId=net.liftweb \ -DarchetypeArtifactId=lift-archetype-blank \ -DarchetypeVersion=2.0-SNAPSHOT \ -DarchetypeRepository=http://scala-tools.org/repo-snapshots \ -DremoteRepositories=http://scala-tools.org/repo-snapshots \ -DgroupId=your.groupId \ -DartifactId=your.artifactId mvn jetty:run mvn scala:cc (jRebel license: http://www.zeroturnaround.com/scala-license/)

D'14 #2& E8#1p0(

http://demo.liftweb.net/ http://github.com/lift/lift/tree/master/examples/

http://github.com/dpp/lift-samples

http://www.liftweb.net

Q7(6-325?

By Gillian Maniscalco http://flickr.com/photos/gillian_m/448800043/