How to properly remove H2 from Grails - grails

Question

I am trying to minimalize my Grails (2.4.2) app and cull out a lot of stuff that create-app generates that I'm just not going to use.
One of these things is H2. I'm just not going to use it, and besides, if I needed an embedded DB, I'd prefer to use HSQLDB.
So I made the following changes to my BuildConfig:
...
// Remove the DB console for all environments, not just dev.
grails.dbconsole.enabled = false
...
grails.project.dependency.resolution = {
inherits("global") {
excludes 'h2'
}
...
}
Now, when I do a run-app, I get the following error:
... <huge stacktrace omitted for brevity>
Caused by: org.springframework.jdbc.support.MetaDataAccessException: Error while extracting DatabaseMetaData; nested exception is java.sql.SQLException: org.h2.Driver
... 4 more
Caused by: java.sql.SQLException: org.h2.Driver
... 4 more
Caused by: java.lang.ClassNotFoundException: org.h2.Driver
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.Class.forName(Class.java:270)
... 4 more
Error |
Forked Grails VM exited with error
What's going on and how do I fix this error while properly removing H2 and any of its configs/references?
Update, my DataSources.groovy file
dataSource {
pooled = true
jmxExport = true
driverClassName = "org.h2.Driver"
username = "sa"
password = ""
}
hibernate {
cache.use_second_level_cache = true
cache.use_query_cache = false
// cache.region.factory_class = 'net.sf.ehcache.hibernate.EhCacheRegionFactory' // Hibernate 3
cache.region.factory_class = 'org.hibernate.cache.ehcache.EhCacheRegionFactory' // Hibernate 4
singleSession = true // configure OSIV singleSession mode
}
// environment specific settings
environments {
development {
dataSource {
dbCreate = "create-drop" // one of 'create', 'create-drop', 'update', 'validate', ''
url = "jdbc:h2:mem:devDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE"
}
}
test {
dataSource {
dbCreate = "update"
url = "jdbc:h2:mem:testDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE"
}
}
production {
dataSource {
dbCreate = "update"
url = "jdbc:h2:prodDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE"
properties {
// See http://grails.org/doc/latest/guide/conf.html#dataSource for documentation
jmxEnabled = true
initialSize = 5
maxActive = 50
minIdle = 5
maxIdle = 25
maxWait = 10000
maxAge = 10 * 60000
timeBetweenEvictionRunsMillis = 5000
minEvictableIdleTimeMillis = 60000
validationQuery = "SELECT 1"
validationQueryTimeout = 3
validationInterval = 15000
testOnBorrow = true
testWhileIdle = true
testOnReturn = false
jdbcInterceptors = "ConnectionState"
defaultTransactionIsolation = java.sql.Connection.TRANSACTION_READ_COMMITTED
}
}
}
}

Answer 1

In your grails-app/conf/DataSources.groovy you probably have some references to the h2 Driver, e.g.
dataSource {
pooled = true
jmxExport = true
driverClassName = "org.h2.Driver"
username = "sa"
password = ""
}
Remove the dataSource configuration completely if you're not using any DB. If you're using a different DB, replace the h2 driver class name with the class name of the driver for your DB.