Add log darkening factor

[dmlloyd]

Configure via quarkus.log.console.darken=<factor> where the factor should be a small integer (2 seems to work well for bright backgrounds).

[cescoffier]

@dmlloyd I will try tomorrow. Wondering if we can use an environment variable for quarkus.log.console.darken (QUARKUS_LOG_CONSOLE_DARKEN if we follow the MP config rules).

Let me explain why:
One of the issue with this approach is the "in-container" usage. I don't really want to have my docker file using the -Dquarkus.log.console.darken=2 neither setting this in the application.config. However, I can use --env or even a global env file (env-file) in my docker run command.

[dmlloyd]

@dmlloyd I will try tomorrow. Wondering if we can use an environment variable for quarkus.log.console.darken (QUARKUS_LOG_CONSOLE_DARKEN if we follow the MP config rules).

Yes, that should work. No, I take that back, I'm not sure it will work. It would definitely work to override an existing value, but I think you'd have to test it otherwise.

[cescoffier]

Unfortunately, it does not seem to work:

The background / color are used are "solarized light" (it's what work well on stage)

[dmlloyd]

I think I can do a one-off fix for this property. I have an idea...

[dmlloyd]

OK with that change you are now able to give the QUARKUS_LOG_CONSOLE_DARKEN environment variable with no other configuration present and it will override the configuration.

[cescoffier]

Thanks @dmlloyd. I will try that tonight (MTZ).

[gsmet]

@cescoffier maybe let's try to get that one in 0.13.1?

[cescoffier]

Just tested.

It's not perfect (basically it's monochrome), but readable enough. Let's merge it like this, and improve it later with colors.

[dmlloyd]

Great! Maybe try with 1 instead of 2 then?

[cescoffier]

I've tried 1, 2 and 3... no much changes

[dmlloyd]

Ah, you probably have a 256-color terminal. Not much else to do in that case unfortunately!

[dmlloyd]

Actually I might be able to use a smoother color increment for 256 mode. Will mess around with it a bit.

[emmanuelbernard]

@dmlloyd Was the binary mode of ligh/dark not working that you went for the darkening factor?
I would say that for the layman user that's a bit confusing this factor ratio.

Also no doc, I'll open an issue for it.

[dmlloyd]

This fix is only meant as a short term workaround for Clement to get through his presentation. I'll come around to fixing it up once logmanager is upstreamed, which I've been steadily working on but has been a slightly lower priority.

I tried making it binary but it seemed that different background colors need different darkening or brightening factors. So I settled on the factor in the end.