Cockroach: log: replace homegrown coloring code

[tamird]

This should be a self-contained task, touching only the logging package.

Related to #14483.

Good one for a first-time contributor.

The code in question: https://github.com/cockroachdb/cockroach/blob/34736b8e24aa242d80ca890cf8b3d0fe1fa4763e/pkg/util/log/clog.go#L788:L823 plus surrounding types.

Three requirements:

1) the new code should abstract the color numeric codes into symbolic names
2) it must test the right file descriptor (stderr, not stdout)
3) it must be conservative about which color codes are sent to which terminal type. Not every terminal supports the same colors.

For example the package at http://github.com/faith/color does not satisfy requirements 2 and 3.

[juanjcsr]

I can work with this one. This will be my first time contributing to this awesome project.

I was looking at the source code of the logging package and it seems like an easy task. I was worried for github.com/faith/color Windows support but I just saw that the latest version now correctly supports it so I hope it does not be too hard

[tamird]

@juanjcsr great! I'm happy to mentor and review your work (reach out to me on our gitter channel if you need help).

Welcome!

[MattBroyles]

I can take a stab at this if it's alright for a first time contributor.

[tamird]

Please do!

[MattBroyles]

I'll get right on it.

[yangliang9004]

Hi, tamird, I have replace homegrown coloring code with https://github.com/fatih/color .. In this case, I need to add the open project "github.com/mattn/go-colorable" to "cockroachdb/cockroach/vendor" . so I copy "github.com/mattn/go-colorable" to the path "cockroachdb/cockroach/vendor". I write a test function to check the output and It runs OK .
But , I still doubt wether it will take effect after it has been merged . How do you mange the open project ? If I need add a new one, what shoud I do ?

[tamird]

@yangliang9004 welcome! Our dependency management workflow is described here.

If you have additional questions, let's discuss in #15587. Thanks!

[knz]

I have added more details about the requirements in the original issue description here: https://github.com/cockroachdb/cockroach/issues/14634#issue-219646919

This highlights that https://github.com/fatih/color is probably not the right package to use, without further changes.

[Ngo-The-Trung]

Is this task still applicable?

[knz]

It is still applicable but please check the requirements!

[knz]

Addressed in #26936.