Custom plugin options

🚀 Feature Proposal

I think it could be useful to allow passing custom options to the plugin defined by the app.js. After reading the discussion at https://github.com/fastify/fastify-cli/issues/26 I would like to propose an alternative approach: exposing a pluginOptions property in app.js, the same way the custom options for Fastify are passed using the options property.

Motivation

In some cases, you might need to define custom options for the app.js and you might want to be able to pass them directly through the options object or let fastify-cli inject them.

Example

app.js

module.exports = function (fastify, options, next) {
  ...
  next()
})

module.exports.options = {} // Cusom Fastify options

module.exports.pluginOptions = {} //Custom plugins options injected by fastify-cli

[dnlup]

The target is clear, I’m not pro to the module.exports.pluginOptions because it is app.js that loads -using env-schema or other logic- the value of this option and so it is not decoupled: the test must know how app.js implemented the loading logic to change the options. So it should be a different actor that exposes those parameters.

I understand your point, and I agree that it should be a different actor. I thought that exposing the options this way would have been more in line with how fastify options are exposed, and I was wrong. Just to be clear, though, I wasn’t suggesting using pluginOptions in tests, but the opposite. I would have used custom objects without knowing how app.js implemented the loading part. Anyway, I agree with you.

For this reason, I’m pro to a powerful -- because the app.js receives the options without knowing how they are loaded at all.

I like this approach too.

(I say powerful because #208 simply decorate the process.argv and this could be optimized as you suggested, in order to be the input options )

Ok, so we can say that after #208 is merged, there is the groundwork for supporting this and that we would like to support it?

If the answer is yes, should I keep this issue open at this point, or should I open a new one?

Thank you again for the feedback.

[mcollina]

I think adding support for passing in args would be nice.