I started a grails application by grails create-app. For modularity, I feel like it would be better that component be a plugin. Can I convert this application into a grails
I never created a plugin based on an application written before but looking at the documentation for grails plugins you can read the following statement:
The structure of a Grails plugin is exactly the same as a regular Grails project's directory structure, except that in the root of the plugin directory you will find a plugin Groovy file called the "plugin descriptor".
So I would suggest to create a new plugin with grails create-plugin *your-plugin-name*
and copy all files from your application into the plugin.
In case anyone else is looking, this should be exactly what you need: http://burtbeckwith.com/blog/?p=1973
Excerpt:
So to convert an application to a plugin, the general workflow would be something like
Create the plugin descriptor, FooGrailsPlugin.groovy. The easiest way to do this is to rungrails create-plugin pluginname and copy the generated file from there
delete everything from application.properties except the app.grails.version property
if you have jars in the lib directory that are available in a Maven repo, delete them and replace with BuildConfig.groovy dependencies
change any plugin and jar dependencies that are needed for development and testing but not when the plugin is installed to not be exported, by adding export = false
If you need the _Install.groovy, _Uninstall.groovy, or _Upgrade.groovy scripts (you probably don’t) grab those from the dummy plugin from step 1 (but delete any you don’t need, they’re all optional)
delete ApplicationResources.groovy if you aren’t using it and don’t depend on resources plugin
move code from BootStrap.groovy init() toFooGrailsPlugin.doWithApplicationContext and/orFooGrailsPlugin.doWithDynamicMethods and destroy() to FooGrailsPlugin.onShutdown, and delete BootStrap.groovy
add a dependency for the release plugin in BuildConfig.groovy
delete everything but the log4j configuration from Config.groovy
delete UrlMappings.groovy unless you have exported mappings; only keep the added ones
move bean definitions from resources.groovy to FooGrailsPlugin.doWithSpring and delete resources.groovy
delete grails-app/i18n message bundle files unless you added messages; only keep the added ones
delete everything from grails-app/views that you don’t use (in particular error.gsp,index.gsp, and layouts/main.gsp)
delete everything from web-app that you don’t use (including WEB-INF xml and tld files)
now would be a great time to write those tests you’ve been meaning to get to
create one or more test applications to install the plugin into to ensure that it works as a plugin; consider scripting this
write documentation for how to use the plugin; at a minimum a README file, but Grails gdoc files would be much better (run grails doc --init to get started)