Renaming composite foreign keys in GORM
Question
I have the following classes:
class Catalog {
static mapping = {
id composite:['name', 'manufacturer']
columns {
name column:'cat_name'
manufacturer column:'manuf_id'
}
}
String name
Manufacturer manufacturer
}
class Order {
static mapping = {
columns {
// How to rename foreign keys as cat_name, manuf_id?
}
}
Catalog catalog // creates catalog_name, catalog_manufacturer_name
}
Presently, an Order table is generated with the attributes catalog_name and catalog_manufacturer_name (which reference the composite primary keys of the Catalog table).
I need to rename these generated columns to cat_name and manuf_id in the Order table to work with an existing database. Is this possible, and if so, how?
Solution
It's not possible using GORM configuration, but you can do it with a custom Configuration class:
package com.foo.bar;
import java.util.Collection;
import java.util.Iterator;
import org.codehaus.groovy.grails.orm.hibernate.cfg.DefaultGrailsDomainConfiguration;
import org.hibernate.MappingException;
import org.hibernate.mapping.Column;
import org.hibernate.mapping.PersistentClass;
import org.hibernate.mapping.RootClass;
public class CompositeAwareHibernateConfiguration extends DefaultGrailsDomainConfiguration {
private static final long serialVersionUID = 1;
private boolean _alreadyProcessed;
@SuppressWarnings("unchecked")
@Override
protected void secondPassCompile() throws MappingException {
super.secondPassCompile();
if (_alreadyProcessed) {
return;
}
for (PersistentClass pc : (Collection<PersistentClass>)classes.values()) {
if (pc instanceof RootClass) {
RootClass root = (RootClass)pc;
if ("com.foo.bar.Order".equals(root.getClassName())) {
for (Iterator iter = root.getTable().getColumnIterator(); iter.hasNext(); ) {
Column column = (Column)iter.next();
if ("catalog_name".equals(column.getName())) {
column.setName("cat_name");
}
else if ("catalog_manufacturer_id".equals(column.getName())) {
column.setName("manuf_id");
}
}
}
}
}
_alreadyProcessed = true;
}
}
Put the class in src/java and register it in DataSource.groovy:
dataSource {
pooled = true
driverClassName = ...
username = ...
password = ...
configClass = com.foo.bar.CompositeAwareHibernateConfiguration
}
OTHER TIPS
This solved my problem (grails 2.0.4):
My case:
class GroupMessage implements Serializable {
Group group
Integer messageId
static mapping = {
datasources(['ds1'])
table 't_group_msg'
version false
id composite: ['group', 'messageId'], generator: 'assigned'
group column:'grpid'
messageId column:'msgid', type:int
}
}
class GroupMessageDetail implements Serializable {
GroupMessage groupMessage
Integer detailId
String message
String url
static mapping = {
datasources(['ds1'])
table 't_group_msg_det'
version false
id composite: ['groupMessage', 'detailId'], generator: 'assigned'
columns {
groupMessage {
column name: 'grpid'
column name: 'msgid'
}
detailId column:'id', type:int
message column:'sms'
url column:'url'
}
}
I have write a solution that is for any domain-class that need it and you don't need readapt every time.
class Catalog {
static mapping = {
id composite:['name', 'manufacturer']
columns {
name column:'cat_name'
manufacturer column:'manuf_id'
}
}
String name
Manufacturer manufacturer
}
class Order {
Catalog catalog
static mapping = {
}
static foreigners = [
catalog : [name : "catalog_name",
manufacturer: "catalog_manufacturer_name"]
]
}
This is the GORM Configuration class that i write to consume the foreigners in the domain class.
package my.app.package
import java.util.Collection;
import org.codehaus.groovy.grails.orm.hibernate.cfg.GrailsAnnotationConfiguration;
import org.hibernate.MappingException;
import org.hibernate.mapping.Column;
import org.hibernate.mapping.ForeignKey;
import org.hibernate.mapping.PersistentClass;
import org.hibernate.mapping.RootClass;
class MyCustomGrailsAnotationConfiguration extends GrailsAnnotationConfiguration{
private static final long serialVersionUID = 1;
private boolean _alreadyProcessed=false;
@SuppressWarnings("unchecked")
@Override
protected void secondPassCompile() throws MappingException {
super.secondPassCompile();
if(_alreadyProcessed){
return;
}
classes.values().each{rootClass ->
if(rootClass instanceof RootClass){
def domainClass= null
Boolean hasForeigners=false
try{
domainClass=Class.forName(rootClass.entityName,false,Thread.currentThread().getContextClassLoader())
hasForeigners = domainClass.metaClass.hasProperty(domainClass, 'foreigners')
}catch(Exception e){}
if(domainClass && hasForeigners){
rootClass?.table?.foreignKeyIterator?.each{fKey->
fKey?.columnIterator?.each{column->
domainClass.foreigners?.each{attrName,columns ->
columns.each{columnItmName,columnItmValue->
def exp=attrName+"_"
columnItmName.split("").each{exp+=(it==~/[A-Z]/) ? "_"+it:it}
exp=exp.toLowerCase()+".(id)\$"
//println "Expression:"+exp
if(column.name.matches(exp)){
//println "Match:"+column.name+" changing to "+columnItmValue
column.name=columnItmValue
}
}
}
}
}
}
}
}
_alreadyProcessed = true;
}
}
Put the my.app.package.MyCustomGrailsAnotationConfiguration.groovy class in src/groovy/my/app/package/MyCustomGrailsAnotationConfiguration.groovy and register it in DataSource.groovy:
dataSource {
pooled = true
driverClassName = ...
username = ...
password = ...
configClass = my.app.package.MyCustomGrailsAnotationConfiguration
}
I hope that will useful for you. Thanks @carlosmain for your help