Display only the running configuration in configurations view

[BasPH]

This PR displays only the running configuration in the configurations view. The (very confusing) default configuration is not displayed anymore. I regularly encounter confusion among Airflow users on this page about what is actually the running value of a config option, because it's not obvious you first have to scroll past the default configuration.

This follows up on #14641, which went stale.

There's an undocumented /configuration?raw=true endpoint to download the config. Users should use the /config endpoint in the REST API instead. I can't imagine anybody using this raw=true endpoint, but added a Deprecation header to the response to indicate the upcoming removal. If there's a better way to indicate deprecation, please let me know.

After:
AIRFLOW__WEBSERVER__EXPOSE_CONFIG=True:

AIRFLOW__WEBSERVER__EXPOSE_CONFIG=False:

Before:
AIRFLOW__WEBSERVER__EXPOSE_CONFIG=True:

AIRFLOW__WEBSERVER__EXPOSE_CONFIG=False:

---

^ Add meaningful description above

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[eladkal]

Looks good

default configuration is not displayed anymore.

I think we should still display defaults because if user is not aware of them he needs to look them up.

Maybe a toggle could solve this as it will allow both states in the same view?

[BasPH]

I think we should still display defaults because if user is not aware of them he needs to look them up.

Why?

I encounter confusion about this page very regularly, people expect this page to show the running configuration. They do not expect the default configuration and are also not interested in knowing the default value when viewing this page, so I don't see the point in showing that.

[eladkal]

I encounter confusion about this page very regularly, people expect this page to show the running configuration. They do not expect the default configuration and are also not interested in knowing the default value when viewing this page, so I don't see the point in showing that.

I agree that now its confusing.
What I meant is to show all configurations that applied to the specific Airflow instance. If user override then show the override value if user didn't then show the default value

[BasPH]

The table is showing exactly that? It shows the active values, plus from where they're configured:

[eladkal]

The table is showing exactly that? It shows the active values, plus from where they're configured

Wasnt sure about that.
LGTM then :)
Very useful improvement!

[potiuk]

Looks cool. very useful to not show defaults and super helpful to see the source of the values.

I think it would be useful but more difficult to show the same values for other components (especially if they differ from the one that webserve sees). This is also an often source of confusion for users especially those who set up a self-managed versions where the values might differ. But this is much more difficult to avhieve via GUI, so this is another story (and discussed/implemented elsewhere).

[BasPH]

Agreed! Also saw failures happening at projects where the configuration wasn't applied consistently to all components, which was difficult to debug because the webserver showed the correct value. It would be cool to build some sort of "configuration-drift-detection", but I'll leave that for another time ;-)