[grails 3]: Replacement of doWithWebDescriptor on Plugin descriptor?

Question

We are trying to move our existing grails 2.5 application to newer versions of grails. For that adopting strategy to first upgrade to grails 3.3.11 (latest in 3.x releases) and then move to grails 4.

For one of the feature from grails 2.5.6 application, I found that there is nothing documented anywhere or may be I've missed that part on the document! It is about Plugin descriptor's doWithWebDescriptor. With this closure we can able to update web.xml dynamically based on some rules.

After upgrading to grails 3, I found that doWithWebDescriptor is not working. It is not initializing task which it supposed to (as far as grails 2.5 concerned). Later I found that there is nothing documented after grails 3.0 documentation.

If doWithWebDescriptor is removed then what is the best suitable replacement with grails 3 or latest grails 4 edition? If it still working fine and there is some configuration related changes required with grails 3 then kindly point me to that part.

Update:

Reason why we need doWithWebDescriptor is that, we are trying to add servlet based on the plugin. Actually we have several plugins for different modules in the application. Not all plugins included in the project. Based on modules selected we are adding plugin to the application. So if a plugin is included then we need to add servlet and a filter to web.xml.

Thank you.

Answer 1

Reason why we need doWithWebDescriptor is that, we are trying to add servlet based on the plugin.

You can add a servlet by registering a ServletRegistrationBean in the application context. You can do that in the plugin's doWithSpring method or in the app's resources.groovy. Example:

Closure doWithSpring() {{->
  myServlet(ServletRegistrationBean, new MyServlet(), "/myServlet/*") {
    loadOnStartup = 2
  }
}}

We have documented this in the 18.5 Hooking into Runtime Configuration section at http://docs.grails.org/3.3.11/guide/plugins.html#hookingIntoRuntimeConfiguration.