Never before in my life I had the opportunity to learn a new technology and put it into productive use within just a couple of days. Grails will change is changing has changed the Java and framework landscape. Using Grails, within less than 3 weeks, an application has been developed that accepts NFC-scans from mobile devices (i.e. Nokia 6131 NFC), sends notifications by email and by SMS, and renders a live view of scans as well. None of the staff involved had any previous experience with Grails whatsoever (I started implementing the domain classes and services, a colleague of mine then took over to implement the GUI while I was on vacation on the Canary Islands). Our work was targeted towards NetBeans, GlassFish and PostgreSQL.

Listed here are the links that helped us jump on the track to wealth, glory and wisdom

1-2-3

• Download Grails
• Get NetBeans Version >= 6.5 (don’t worry, NetBeans allows more than one version to be installed) NetBeans 6.5 Beta suffers from regression bugs affecting Grails/Groovy/Subversion, e.g. Issue 142724. Use NetBeans 6.5 M1 instead (download, archives, 6.5, milestone,…) Besides that, I experienced drastic problems checking out existing Java projects from subversion, so for now I recommend to stick with NetBeans 6.1 for Java production projects.
• NetBeans Grails Integration Watch out: With NetBeans 6.5 M1+Beta and Windows, don’t use Run from NetBeans, because Jetty won’t stop unless either being killed or you log off. Use grails run-app from command prompt instead (see also Issue 138116)
• Have a look at Groovy: Groovy Beginners Tutorial (don’t skip this)
• optional: Grails Quick Start Tutorial
• Learn Grails: Getting Started with Grails
• Read the books: Beginning Groovy and Grails: From Novice to Professional (by Christopher M. Judd, Jun 2008, my favorite one) and of course The Definitive Guide to Grails (by Graeme Rocher, 2006, available as eBook/PDF, new edition scheduled for Jan 2009)

Links

• http://www.grails.org/
• New (as of 2014): Grails Cookbook (http://grails.asia)
• Build your first Grails application, The Grails event model and 6 more from IBM: Mastering Grails Series.
• http://www.g2one.com/ (the commercial sibling of Grails)
• Grails Framework Reference Documentation, and as single html
• http://docs.codehaus.org/display/GRAILS/Home and Groovy Pages at Codehaus – Tree View
• For those new to both Java and Groovy, Groovy Operators and Groovy Regular Expressions
• HQL – The Hibernate Query Language and Hibernate – Working with objects
• Search for Grails on DZone DZone is a free link-sharing community for developers
• Groovy & Grails eXchange conferences, don’t miss Previous Years (see also Grails eXchange Videos on Google)
• Graeme Rocher’s Blog (working 24 hours a day, Grails bugs fixed within last 3 months)
• Graeme Rocher’s Blog at NFJS (NFJS – No Fluff Just Stuff conferences)
• Guillaume Laforge’s Blog
• Jeffs Groovy Web Log (G2One)
• Jason Rudolph Blog (author of Getting Started with Grails)
• Grails cheatsheet / quicksheet draft is here
• Using the dbmigrate plugin with Grails (Google Code)
• Ruby on Rails^TM, Rails for short, the rails within Grails
• Grails 1.0-RC1 Release Notes
• http://grails.org/Validation+Reference
• Dynamic Finders within Persistence Basics
• Thoughts and Ideas: PostgreSQL and Grails (statements for datasource.groovy)
• Practical Prototype and script.aculo.us (by Andrew Dupont, available as PDF too)

Pet stores, sort of:

• A lot of Grails sample applications and Grails open source projects
• 24 Hours of groovyblogs.org: source now available, download from Google Code (or still better check out from SVN), Live-App at http://www.groovyblogs.org/
• FiBiRi.com running on Grails
• Sample Store Catalog using using Groovy and Grails (Sample Store Catalog using using Groovy and Grails and the Java Persistence API on Glassfish with MySQL
• grails-petstore (Google Code, fragment!)
• 7 year old girl implements Pet Store

The web service side:

• What a pity – doesn’t work with GlassFish: Grails + Metro – Contract First Web Service, Grails and web service development with Metro : Martin Grebac and Metro Plugin for Grails Framework (see attachments)
• Ok – in GlassFish, but no client: Grails – XFire plugin
• not yet evaluated: Apache Axis 2 Plugin
• tedious? GroovyWS + Groovy Web Service and Consuming FedEx Web Services from Grails using Apache CXF
• Inject “session” into Grails Service, see also Class GrailsWebRequest
• soapUI (ad-hoc web service testing and more), WebStart and IDE Plugins available, a must-have!

Still more advanced:

• Creating a Grails Plugin in NetBeans IDE (Geertjan’s blog)

Slightly off topic:

• Silk icons (700 ready to use free ones, but have a look at Fotolia too)
• Guicy: a Groovy Guice? (Guice @Inject instead of factories for Java)

Tiddlers:

• Groovy Truth (how Groovy coerces to boolean, a must-read)
• Grails – WebFlow (Spring Web Flow for Grails)
• The Grails Application Generator (Import and export Grails-Domains from/to both databases and UML, Beta)
• Grails Widget list… (set type of widgets within constraints , e.g. description(widget:’textarea’), in case description has no maxSize but should still be rendered within textarea)
• Sh*tmores: Grails + Ext Grid Mini Tutorial
• Grails on Sakila (Marcel Overdijk playing with Grails and YUI, e.g. slick scaffolding templates using YUI)
• Scaffolding with Dojo Grid (and Grails)
• Grails scaffolding – improved list page
• Grails Scaffolding
• Grails & Locales
• OpenID Plugin Very cool! For heavy-weight enterprise apps, use in conjunction with Acegi. Have a look at OpenID user registration on Grails and at http://curious-attempt-bunny.blogspot.com/2008/07/playing-with-grails-openid-integration.html for quick-and-dirty patterns. Get your instant !OpenIDs either from Google or from Verisign Personal Identity Portal(PIP).
• JSecurity Plugin
• Using Groovy to Send Emails – Towards a DSL: Groovy + Ant (html mail) and Grails: Sending email using Ant with GMail SMTP server and Ant Mail Task, send SMTP mail using JavaMail with gmail account (ran into problems on GlassFish when using SSL), Java Tip 115: Secure JavaMail with JSSE
• Grails Mail Plugin (if only I had known this in advance…, note: I’ve not yet confirmed its operation within containers like GlassFish)
• Sending SMTP Authenticated Email, Html content with GroovyTemplates and Spring integration
• Groovy Templates (use them for your own app as well)
• Grails Service, JMS and an MDB and JMS Plugin (e.g. for serving asynchronous requests within an environment that hates new Thread())
• My first Grails plugin (Jetty only, does not work with GlassFish) Plugin adding …/static/resources/ to your Grails project allowing arbitrary resources to be packaged and downloaded, see jettystatic at Google Code
• Enabling HTTP Compression in GlassFish

Deutsche Ecke (German corner, don’t hold your breath yet):

• Groovy- und Grails-Forum
• Groovy- und Grails-Wiki
• Groovy Grails User Group Hamburg

Watch out

• Within its domain classes section, Getting Started with Grails refers to deprecated optionals. Use nullable:true within constraints instead.
• Constraint password:true is undocumented. Causes type=’password to be generated instead of type=’text. Does not affect scaffolding lists (change exlude from within template in order to hide)
• This bug affects Windows only: NetBeans versions 6.5 M1+Beta are unable to stop Grails scripts causing bind failed, port 8080 already in use when using Run within NetBeans. Work-Around: Start from command prompt using plain vanilla Grails: grails run-app. See Issue 138116 – Stopping a running app doesn’t stop the child process
• Auto Compile should be named Mostly Auto Compile grails run-app sometimes needs to be restarted in order for changes to source files to have any effect. And if that doesn’t help do a grails clean as well.
• Grails, Jetty, Glassfish and JNDI Data Sources – Glen Smith
• Mano’s Tech World » Blog Archive » Grails 1.0.3 upgrade issues (e.g. trouble with blanks in paths)
• AuditLogEvent domain object fails to save on PostgreSQL and Oracle databases
• Events and Auto Timestamping (attributes within domain classes named dateCreated and lastUpdated)
• Reserved Names
  • Any SQL keyword you might think of (and still more you don’t know yet)
  • PostgreSql: User – that’s a nasty one when working with tutorials
  • Grails: application
  • action (heaven knows)