Regular SQL query result mapped to Grails domain class

It's often needed to do a regular SQL query if Criteria or HQL query isn't flexible enough. This is achieved with Hibernate's org.hibernate.SessionFactory class function createSQLQuery. However query's list-method returns a List of objects inside of a List by default instead of List of domain instances. Luckily org.hibernate.SQLQuery class has a method named addEntity which can be used to map results to specific domain class.

Our domain class:
package fi.company.domain
class Product {
   String name
   int price
}


Service that uses sql
import org.hibernate.SessionFactory
import org.hibernate.Session
import org.hibernate.SQLQuery
class ProductSearchService {
   SessionFactory sessionFactory
   boolean transactional = false


   List<Product> searchProducts(Map params) {
      Session session = sessionFactory.getCurrentSession()
      SQLQuery sqlQuery = session.createSQLQuery("SELECT * FROM product WHERE ...")
      sqlQuery.addEntity(fi.company.domain.Product.class)
      return sqlQuery.list()
   }
}

Delete records with Hibernate Criteria Builder

A neat way of deleting records with createCriteria and Groovy:

def c = Agency.createCriteria().list {
   eq("agency", "XXX") 
}*.delete()

Source: http://stackoverflow.com/questions/2232621/how-do-you-bulk-delete-records-in-grails-gorm

Check if JSON object is undefined

on the callback of jQuery.getJSON(), you want to check if json.myObject is undefined. It's done in a groovy way:
function(json){
if (json.myObject){
// do stuff with myObject
} else {
// do not do stuff with myObject
}
}

Accessing Taglib from Service

From the service:

class MyService {
    def grailsApplication
    
    def method() {
        def g = grailsApplication.mainContext.getBean('org.codehaus.groovy.grails.plugins.web.taglib.ApplicationTagLib')
    }
}

...now g can be used just as in GSP files.

Mystical message codes for numerical validation constraints

minSize -> class.prop.minSize.notmet
maxSize -> class.prop.maxSize.exceeded
size -> class.prop.size.toosmall & class.prop.size.toobig

min -> class.prop.min.notmet
max -> class.prop.max.exceeded
range -> class.prop.range.invalid (only if validated value is null), class.prop.size.toosmall , class.prop.size.toobig

Hibernate-plugin refuses to install: A workaround

Failed to install plugin [hibernate-1.2.2]. Plugin has missing JAR dependencies.

How to fix this? No clue, but a workaround is to clear the ~/.ivy2 directory.

Using session-scoped services in Grails' taglib

Using services with session scope in tag libraries does not work in Grails, as per version 1.2.2. There's a fix promised in 1.3.0, but while waiting for it to be released, here's a simple workaround:

import org.springframework.context.ApplicationContextAware
import org.springframework.context.ApplicationContext

class DefaultTagLib implements ApplicationContextAware {
  ApplicationContext applicationContext

  def someTag = {attrs, body ->
    applicationContext.documentService.doSomething()
  }
}

Setting environment variables for Grails on OSX

The best place to store environment variables on OS X is /etc/launchd.conf. The contents of that file are accessible by console applications, and also (unlike ~/.bashrc and the like) by desktop applications.

Paths should be defined in /etc/paths.

In /etc/launchd.conf:

setenv JAVA_HOME /Library/Java/Home
setenv GRAILS_HOME /Developer/grails-1.2.1

In /etc/paths:

/Developer/grails-1.2.1/bin

Max-width / max-height in IE

IE does not play nice with max-width and max-height. Here's how to handle it...

/* real browsers */
max-width: 500px;
max-height: 500px;

/* IE */
width: expression(this.width > 499 ? "500px" : "auto");
height: expression(this.height > 499 ? "500px" : "auto");

Java VM options for Grails usage

When developing large(ish) Grails applications, you probably will need to adjust your heap and permgen sizes. Here be the Options!

-Xmx512m -Xms512m -XX:MaxPermSize=128M

How to protect everything from XSS

Simply, add .encodeAsHTML() to everything that users have input on and are printed to views.

For example, if the malicious user changes his/her name to <script src="evilscript.js">giveMeAdminRights(); </script> , using user.name.encodeAsHTML() will prevent the script from being run when the admin views the user's profile.

Also the fieldValue tag will do the same, like this: <g:fieldValue bean="${user}" field="name"/ >

The IE 7 z-index problem

Ok, this one is not Grails, but still it took a painful while to get my head around: The IE 7 z-index problem.

ApplicationContext

Accessing application context

import org.springframework.context.ApplicationContextAware
import org.springframework.beans.BeansException
import org.springframework.context.ApplicationContext

class MyServiceOrController 
  implements ApplicationContextAware {
    
  def applicationContext    

    def void setApplicationContext(
      ApplicationContext appctx) throws BeansException {
        applicationContext = appctx
    }
}

Running Grails commands in specific environment

Every now and then there's a need to run Grails commands from command prompt, in a specific environment. For example, to create a WAR in demo environment:

grails -Dgrails.env=demo war

Importing stuff in GSP files

Sometimes (pretty often, actually) there's a need for importing classes inside GSP files. Here's how the syntax goes:

<%@ page import="fi.company.project.enums.ThingType" %>