gh-131952: Add color to the json CLI

[tomasr8]

Example:

I'm open to changing the colors. For now it's green for strings, yellow for numbers and cyan for true/false/null.

• Issue: Color in json.tool CLI #131952

[StanFromIreland]

How much of a performance impact does this have?

[picnixz]

How much of a performance impact does this have?

It doesn't matter here. json.tool is more of a visualization tool. If users don't want to colorize the output they can also disable it using the NO_COLOR env. var IIRC. OTOH, we could add an explicit --pretty flag to enable colorization instead of making the default.

[tomasr8]

OTOH, we could add an explicit --pretty flag to enable colorization instead of making the default.

I think we might not need that, can_colorize can already detect most situations where color is not desirable (e.g. not a TTY). You can also set NO_COLOR to turn off colors unconditionally.

[picnixz]

What about CLIs? they would be broken if data is piped?

[tomasr8]

What about CLIs? they would be broken if data is piped?

AFAIU they wouldn't (and local testing confirms that), see this comment from Hugo: #131952 (comment)

[raztd]

@tomasr8 thank you for taking the time to look into it. couple of notes regarding the keys 1) could you make them a different color from the string values? 2) could you make them bold?

this is what jq does and i think it provides a good ux https://static1.howtogeekimages.com/wordpress/wp-content/uploads/2020/01/5-7.png

[tomasr8]

@tomasr8 thank you for taking the time to look into it. couple of notes regarding the keys 1) could you make them a different color from the string values? 2) could you make them bold?

this is what jq does and i think it provides a good ux https://static1.howtogeekimages.com/wordpress/wp-content/uploads/2020/01/5-7.png

That should be in theory possible, we can distinguish keys from string literals since keys are always followed by :. I will make a couple different color versions and then we can decide which one looks the best.

[python-cla-bot]

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[picnixz]

Can we move the helper functions before the main function? it's easier to read when you're coming from the bottom of the file (and make them private so that someone is not using them by importing json.tool?)