Question

I have a following piece of code which connects to database and executes a query, I have a no clarity in placing of this code(Model/Service).

def value
def url      = ConfigurationHolder.config.dataSource.url
def username = ConfigurationHolder.config.dataSource.username
def password = ConfigurationHolder.config.dataSource.password
def driver   = ConfigurationHolder.config.dataSource.driverClassName
def sql      = Sql.newInstance(url, username, password, driver)

sql.eachRow("select field_value from application_configuration where field_name=?", [field]) {
        value=it.field_value
}

I have a class called ApplicationConfiguaration, I am querying on this domain.

I have two doubts

1) where to put the Database connection logic
2) where to put the query execution logic

Answer 1

If you haven’t created a domain object to represent application_configuration, you should consider that, and use domain object finders or HQL.

If you need to perform the query outside of GORM, it should probably go in a service. Note that a DataSource object can be automatically injected into your service and that a Sql object can be created directly from it. You could have something like this:

import groovy.sql.Sql

class ApplicationConfigurationService {
    def dataSource

    def valueForName(name) {
        def sql = new Sql(dataSource)

        sql.eachRow(...) {
            value=it.field_value
        }
    }
}