I developed a plugin that registers a convention and a bunch of tasks. The convention mostly holds file paths.
I also created a task that uses the file paths defined within the convention
I am now wondering if i should be accessing the convention directly from the task or whether i should be using the conventionMapping to set the values the task uses as defaults.
For many tasks i imagine, using the conventionMapping would be the best approach because that lets you reuse the task in a standalone way. However in this case the file paths not something you would override in any scenario and if i made every path a property of my task then using the task in a standalone fashion would be painful because if i understand correctly then each of the paths would have to be set manually by the caller.
Is it acceptable in that case to access the convention directly from the task ? Or is there some other clever technique i can use that allows these properties to be defaulted to a convention when used directly
Usually, convention objects (which have, for the most part, been replaced with extension objects) will be at a higher level of abstraction than the tasks. Otherwise, users could also configure the tasks directly with ‘tasks.withType(…) { … }’.
Whether to couple the tasks to the convention/extension object is a judgement call that you’ll have to make. As a general guideline, the more likely you are going to publish the plugin to third parties, the less likely you should have a tight coupling.
Thanks for the response. So I guess I should be using extension objects then ? Do you know of any resources that describe the differences between extensions and convention objects? Should you now always be using extension objects?
Start out by studying the “Writing Custom Plugins” chapter in the user guide. After that, have a look at some of the plugins in the Gradle codebase, for example the code quality plugins.
Unless you know exactly what you are doing and have a concrete reason to go with convention objects (and there aren’t many), you should always prefer extension objects. They are both easier to use and safer.