Adding JNDI to embedded Tomcat server in Grails 3

Question

When running test-app in grails 3.0, or run-app, grails runs its own version of the embedded Tomcat server. I was able to conclude this from the following link: https://rosh

Answer 1

In Grails 3, you do it like this: SampleTomcatJndiApplication

Typically, in Grails web applications, this is in /grails-app/init/Application.groovy

(In my case, I commented out the jndiDataSource() part and just used postProcessContext().)

Source: Graeme Rocher

Answer 2

The solution to this issue is addressed in two steps. First, I had to use the child approach to setting the right context, found in this question. Setting the right context in embedded Tomcat

As imagined, The only change I then had to make was to the getTomcatEmbeddedServletContainer method. I have edited the original to look like this:

@Override
protected TomcatEmbeddedServletContainer getTomcatEmbeddedServletContainer(Tomcat tomcat) {
    tomcat.enableNaming();
    TomcatEmbeddedServletContainer container =
    super.getTomcatEmbeddedServletContainer(tomcat);
    for (Container child: container.getTomcat().getHost().findChildren()) {
        if (child instanceof Context) {
            ClassLoader contextClassLoader =((Context)child).getLoader().getClassLoader();
            Thread.currentThread().setContextClassLoader(contextClassLoader);
            break;
        }
    }
    return container;
}

Next, I had to edit the gradle build file, to include the dbcp BasicDataSource Dependency. My gradle build file now contains:

dependencies {
    // Embedded tomcat dependencies
    compile "org.apache.tomcat:tomcat-dbcp:9.0.0.M1"
}