Console still doesn't quite work with Ractors

[Forthoney]

I really appreciate the quick response with #54 , but it still doesn't seem to be fully compatible with Ractors.
I'm still running into an error with my architecture
'write': can't modify frozen IO: #<IO:<STDERR>> (FrozenError)

The full stack trace is
.../console/terminal/logger.rb:116 in call .../console/filter.rb:148 in call .../console/filger.rb:40 in block (3 levels) in []
and my architecture can be found here

[ioquatix]

Thanks, I'll take a look.

[ioquatix]

Do you have any way to reproduce the error? I couldn't figure out how to reproduce it.

[ioquatix]

I managed to make a similar reproduction:

> Ractor.make_shareable(STDERR)
=> #<IO:<STDERR>>

> Ractor.new{STDERR.puts "Hello"}

#<Thread:0x000000012b473408 run> terminated with exception (report_on_exception is true):
(irb):2:in `write': can't modify frozen IO: #<IO:<STDERR>> (FrozenError)
	from (irb):2:in `puts'
	from (irb):2:in `block in <top (required)>'
=> #<Ractor:#2 (irb):2 running>

Any time $stderr can leak into or out of a Ractor, it looks like it can become frozen and then operations may fail. I also noted at least once IO#tty? failed for the similar reason.

[ioquatix]

One thing I can suggest is don't share Console.logger instances anywhere. Only use Console.logger.info (or other log levels) OR better Console.info only. Sharing logger instances may trigger the above situation.

[Forthoney]

My guess as to why the frozen error occurs is when objects are sent over as messages between ractors, ruby implicitly freezes things that can be frozen (it even does this recursively). The IO object is probably being frozen as Console is being passed between ractors. So, this is more so a limitation with Ractor messages than with Console.

In case other people also encounter this challenge, I'll briefly explain here what I did. To work around this limitation, I made it so that there is one "logger" ractor that actually holds on to the Console::Logger. In other ractors, I modify Console::Logger method calls to instead send a message to the "logger" ractor who will then log on behalf of the sender. It's essentially a RPC between ractors. This way, the IO object is not shared between Ractors, but the worker ractors can continue on using Console like normal.

Here's the code for what I do. I just include the module everywhere where Console is used except the logger.

[ioquatix]

The Console class does this already, e.g. Console.info - so if you need to pass a logger, pass Console itself. In theory you can redirect this easily too, using an output layer. I'll try to take a look at your code if I have a moment.