Add fastify.url to return the current url of the application

[mcollina]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the feature has not already been requested

🚀 Feature Proposal

I think we should add fastify.url as it would be a convenient API.
I spend way too much time coding http://localhost:${server.server.address().port, so maybe we could get it done in Fastify itself.

Wdyt?

Motivation

No response

Example

In Platformatic, we addded:

https://github.com/platformatic/platformatic/blob/d8ad6a97e552c4d2c365a27b1a427738aaa6833c/packages/service/index.js#L208-L215

[climba03003]

We should also provide the correct protocol based on server setting (maybe server instance class would be better).

[mcollina]

Yes, exactly

[jsumners]

How is this different from the discussion in #387?

[climba03003]

How is this different from the discussion in #387?

In the discussion is used for requset.
In here is used for a friendly shortcut for test-case.

Another main different is one of them depends on header, one of them depends on server startup setting only.

[Uzlopak]

i already see that people report bugs, saying that fastify.url does not respect their top level domain and just report http://127.0.0.1:3000 (instead of http://www.mysecret.tld:3000)

[mcollina]

Ouch, now that I think about it, it will likely happen. Maybe we should call it localUrl instead?

[climba03003]

Or listenHost / listenOrigin ?

[mcollina]

listenOrigin is likely the more correct one

[Uzlopak]

I would prefer something like originUrl as listen is a Verb indicating a function.

[climba03003]

I would prefer something like originUrl as listen is a Verb indicating a function.

originUrl does not indicate what origin it is. and it is odd to have both origin and url since origin is part of url.

Would listeningOrigin or currentListeningOrigin be specific enough?

[mcollina]

listeningOrigin would work for me.