The Console - who owns it? who can interact with it?

[dmlloyd]

tl;dr - We do not have a very good abstraction for managing the console at present; maybe we can analyze this problem a bit.

The console could conceivably be used in any of the following ways in a Quarkus application (non-exhaustive list) - and maybe more than one at once:

• Logging (to print the logs, obviously)
• Logging again (to discover the terminal capabilities so we can correctly solve Color scheme in Quarkus devmode and logs not adapted to light backgrounds #28869, Support graphical banners #40226, etc.)
• Interactive prompts including reading passwords (up to and including jline usage)
• Non-interactive progress reporting
• Raw, machine-readable output for another stage or process to consume (JSON logging for example)
• As I/O for a socket channel
• Produce one-time output (like a report generator)
• (Probably more cases I'm not thinking of now)

We do not have a single, reliable way to arbitrate access to the console (that I am aware of), but we need one (in my opinion).

I'd want an API that would let me do the following:

• Perform console capability queries (with a nice failure path if there is no console or if the console has only basic I/O capabilities)
• Request exclusive access to the console (for example, for a full-screen terminal app, or for writing large control structures like graphical banners or displaying images)
• Maybe: request interactive access to the console (not exclusive) including the ability to enter passwords
• Maybe: request logging/printing access to the console (in such a way that interactive access isn't disturbed; e.g. inserting log lines before the interactive prompt)
• Maybe: request or provide a progress bar mechanism for the console (if supported)

Maybe something like jline or jansi would get us most of the way here. I'm sure we're using those things individually, but it would be nice to coordinate it in a clear API (without configuration) so that e.g. logging isn't fighting against the interactive app.

Thoughts?