Types Migration

[antoniomuso]

The current types do the overloading of Fastify default types, this creates the problem that we found the plugin types also in data type not reached from the plugin.

fastify.get<ReqReplyMetrics, MetricsConfig>(
        '/',
        { config: { metrics: { metricId: '' } } },
        (request, reply) => {}
    );

For this reason, we can evaluate the migration to generics typing, in this way, it is the user's responsibility to type his data.

[dnlup]

I've looked into this lately, and I agree with you, the downside of this approach is that we have to use the generics in every point we need it 🤔 , that could be cumbersome in my opinion.

/cc @mdoria12