docs: adding reference guide

[lirantal]

Adding a section to list helpful resource guides to get started with building with env-schema

Fixes #142

Checklist

• run npm run test and npm run benchmark
• tests and/or benchmarks are included
• documentation is changed or added
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[mcollina]

Could you split creation of the Fastify application with the call to listen in two files, as this enables testing without using globals?

[lirantal]

Sure thing. I was going for simplicity there but have merged a PR to change that to a more modular structure: lirantal/fastify-dotenv-envschema-example#1 (landed in main already)

[climba03003]

Shouldn't it place in @fastify/env when you did not directly using env-schema?

[lirantal]

It's a good question and I was asking myself the same thing but I thought the ideal place is here because folks using the @fastify/env plugin would probably already know best practices and how to use it, yet new folks landing on this repository might look for how to get started and how they can use env-schema, especially since it doesn't have anything to do with Fastify as the app framework itself, but just happens to live on this org.

So, I'd keep it here to be more helpful but happy to move elsewhere if you think it'd be a better fit.

[mcollina]

I personally find env-schema better and I don't use fastify-env ;).

[lirantal]

fastify-env is pretty small and is anyway just a wrapper around env-schema though, isn't it? I figured if you don't use fastify-env you probably just do the same plugging wrapping yourself.

[mcollina]

I tend to not wrap this into a plugin, but rather read it before Fastify is started. In this way I can customize the options of Fastify itself

[jsumners]

I tend to not wrap this into a plugin, but rather read it before Fastify is started. In this way I can customize the options of Fastify itself

Agreed. I really don't understand the point of fastify-env.

'use strict'

const dotenv = require('dotenv')
const config = dotenv.config()

const fastify = require('fastify')({ /* use stuff from config */})
fastify.decorate('env', {
  getter() { return config }
})

[mcollina]

lgtm