8.1. Taking advantage of others’ hard work

When might you want to install a plugin? If you find yourself with a feature requirement that doesn’t sound specific to your application—one that’s not directly related to your business logic—look out for existing plugins that promise to do the job for you. If you would use a separate library or tool to do the job in a plain Java project, then a plugin is probably the best solution in Grails. Remember, it’s rarely a good idea to reinvent the wheel.

Take Hubbub, for example. We’ll want to send emails from various parts of the application, such as a user registration module or a daily email digest module, but emailing isn’t what Hubbub is about. The feature is outside the core of Hubbub and is common to lots of different types of applications. That makes it an ideal plugin candidate, and you won’t be surprised to learn that an email plugin already exists.