lsug-lift.pdf

London Scala User Group introduction to Lift web development, 8 March 2010.

Transcript

1. Getting started with Lift Richard Dallaway, @d6y richard@taykt.com
2. lsug.org
4. Struts Grails Rails PHP JSF Wicket GWT JAX-RS Stripes Spring MVC Play Seam Seaside Lift Cocoon WebObjects
5. Struts Grails Rails PHP JSF Wicket GWT JAX-RS Stripes Spring MVC Play Seam Seaside Lift Cocoon WebObjects Zero Plenty Weirdness
6. ‛ ‛ ‛ ‛ http://liftweb.net
7. Versions 1.0.3 Updated Jan 2010 2.0 M2 Released Feb 2010 both for Scala 2.7.7
10. lift-base/lift-actor lift-base/lift-common lift-base/lift-json lift-base/lift-util lift-base/lift-webkit lift-modules/lift-amqp lift-modules/lift-facebook lift-modules/lift-imaging lift-modules/lift-jta lift-modules/lift-ldap lift-modules/lift-machine lift-modules/lift-oauth lift-modules/lift-openid lift-modules/lift-osgi lift-modules/lift-paypal lift-modules/lift-testkit lift-modules/lift-textile lift-modules/lift-widgets lift-modules/lift-wizard lift-modules/lift-xmpp lift-persistence/lift-couchdb lift-persistence/lift-jpa lift-persistence/lift-mapper lift-persistence/lift-record $ find . -name lift\* -depth 2 -type d
11. Agenda • Part I: View first • Part II: Doing stuff quickly • Part III: Ajax • Part IV: Real time web
12. The time on this server is: Mon Mar 08 18:40:51 GMT 2010.
13. <html xmlns="http://www.w3.org/1999/xhtml"> <body> <h1>Hello world</h1> <p>The time on this server is: <lift:Time.now> time appears here </lift:Time.now> </p> </body> </html>
14. package com.myproject.snippet import scala.xml.NodeSeq class Time { // My <lift:Time.now /> implementation: def now(xhtml: NodeSeq) = <span>{new java.util.Date()}</span> }
15. <html xmlns="http://www.w3.org/1999/xhtml"> <body> <h1>Hello world</h1> <lift:Time.now> <p>It’s <when:day/> at <when:hour/>.</p> </lift:Time.now> </body> </html>
16. package com.myproject.snippet import scala.xml.{NodeSeq,Text} import net.liftweb.util.Helpers._ class Time { def now(xhtml:NodeSeq) = { val day = "Monday" val hour = "7 o'clock" bind("when", xhtml, "hour" -> <span>{hour}</span>, "day" -> Text(day) ) } }
18. <html xmlns="http://www.w3.org/1999/xhtml"> <body> <h1>Hello Canada</h1> <lift:Olympics.results> <table> <table:rows> <tr> <td><r:country>Country here</r:country></td> <td><r:golds>Gold medal count</r:golds></td> </tr> </table:rows> </table> </lift:Olympics.results> </body> </html>
19. package com.myprojects.snippet import scala.xml.NodeSeq import net.liftweb.util.Helpers._ class Olympics { case class Golds(country: String, medals: Int) def results(xhtml: NodeSeq) = { val vancouver = Golds("CAN", 14) :: Golds("GER", 10) :: Golds("GBR", 1) :: Nil // <table:rows> <r:country/> <r:golds/> </table:rows> bind("table", xhtml, ! ! "rows" -> vancouver.flatMap( gold => bind("r", chooseTemplate("table", "rows", xhtml), "country" -> gold.country, "golds" -> gold.medals ) ) ) } }
21. $ mvn archetype:generate \ -DarchetypeCatalog=http://scala-tools.org/ Choose archetype: 1: http://scala-tools.org/ -> scala-archetype-simple (A simple scala project) 2: http://scala-tools.org/ -> lift-archetype-blank (A blank/empty liftweb project) 3: http://scala-tools.org/ -> lift-archetype-basic (A basic liftweb project (with DB, css, ...)) Choose a number: (1/2/3):
22. $ mvn archetype:generate \ -DarchetypeGroupId=net.liftweb \ -DarchetypeArtifactId=lift-archetype-blank \ -DarchetypeVersion=2.0-M2 \ -DremoteRepositories=http://scala-tools.org/repo-releases \ -DgroupId=com.example.proj
23. package com.brightonbloggers.admin.model import net.liftweb.common._ import net.liftweb.util._ import net.liftweb.mapper._ import net.liftweb.http._ class Blog extends LongKeyedMapper[Blog] with IdPK { def getSingleton = Blog object title extends MappedString(this, 20) object url extends MappedString(this, 100) { override def validations = isUrl _ :: super.validations } def isUrl(u:String) = if (url startsWith "http") ! ! ! ! ! ! ! Nil ! ! ! ! ! ! else ! ! ! ! ! ! ! List(FieldError(url, S.?("field.url.error"))) } object Blog extends Blog with LongKeyedMetaMapper[Blog] with CRUDify[Long,Blog] { }
24. <lift:surround with="default" at="content"> <h1>Ajax blog</h1> <div id="list"> <lift:Blogs.list> <ul> <directory:entry /> </ul> <directory:new_blog /> </lift:Blogs.list> </div> </lift:surround>
25. import com.brightonbloggers.admin.model.Blog import scala.xml._ import net.liftweb.common._ import net.liftweb.mapper._ import net.liftweb.http.SHtml._ import net.liftweb.http.js.JsCmds._ import net.liftweb.util.Helpers._ import net.liftweb.http.S._ class Blogs { def list(xhtml: NodeSeq): NodeSeq = { ! def add_new_blog(s: String) = { Blog.create.url(s).title(s).save SetHtml( "list", list(xhtml) ) } bind("directory", xhtml, ! ! "entry" -> Blog.findAll().flatMap( b => <li>{b.url}</li> ), ! ! "new_blog" -> ajaxText("", add_new_blog _) ) } }
26. package com.brightonbloggers.admin.snippet import com.brightonbloggers.admin.model.Blog import scala.xml._ import net.liftweb.common._ import net.liftweb.mapper._ import net.liftweb.http.SHtml._ import net.liftweb.http.js.JsCmds._ import net.liftweb.util.Helpers._ import net.liftweb.http.S._ class Blogs { def list(xhtml: NodeSeq): NodeSeq = { ! def add_new_blog(s: String) = { Blog.create.url(s).title(s).save SetHtml("list", list(xhtml) ) } def update_blog(blog: Blog)(new_value: String) = { blog.url(new_value).save SetHtml("list", list(xhtml) ) } def click_to_edit(blog: Blog) : NodeSeq = ! ! swappable( <li>{blog.url}</li>, ! ! ! ajaxText(blog.url, update_blog(blog) _ ) ) bind("directory", xhtml, ! ! "entry" -> Blog.findAll().flatMap( click_to_edit _ ), ! ! "new_blog" -> ajaxText("", add_new_blog _) ) } }
28. $MJFOU 4FSWFS 5JNF #SPXTFS6* $0.&5$MJFOU User Activity Client Processing Display Display Display Comet Event Bus Initialization Data Push Data Push Data Push Display Display Data Push Data Push Server-Side Processing Event Event Event Event Event
29. def list(xhtml: NodeSeq): NodeSeq = { ! def countable(blog: Blog) : NodeSeq = ! <li>{link("/static/list", () => { StatsServer ! blog }, Text(blog.url)) }</li> bind("directory", xhtml, ! ! "entry" -> Blog.findAll().flatMap(countable _) )
30. package com.brightonbloggers.admin.comet import net.liftweb.http._ import net.liftweb.common._ import net.liftweb.util.Helpers._ import net.liftweb.http.js._ import net.liftweb.actor._ import net.liftweb.http.js.JsCmds._ import scala.xml._ object StatsServer extends LiftActor with ListenerManager { var count = 0 override def lowPriority = { case b => count = count + 1 updateListeners() } def createUpdate = count } // <lift:comet type=”StatsWatch” /> class StatsWatch extends CometActor with CometListenee { def registerWith = StatsServer override def render = <div id="total">0</div> override def lowPriority = { case count: Int => partialUpdate(SetHtml("total", Text(count.toString))) } }
31. Thank you. • Lift book: http://groups.google.com/group/ the-lift-book • Liftweb.net: Wiki, mailing list, getting started guide • Visit lsug.org, join the meetup.com group
32. apress discount code LONDONSCALAUQUCUAVGLT
33. Next Meeting Traits & Mixins Kevin Monday 12 April Here, Skillsmatter