Use the current user's SDKMAN installation

[reitzig]

When su-ing to another user, environment variables carry over.
As a result, sdk will point to the installation of the original user,
not the one running the current shell.

Thus: Reset $SDKMAN_DIR if the directory it points at
belongs to a user other than the current one.

(Sorry, I didn't have the time to fulfill the prerequisites. I empathize, but that doesn't change my time prioritization.)

[marc0der]

Although I do see the point, the implementation does feel a bit hacky to me.
Can we assign this expression to a clearly named variable? Can we unset said variable at the end of the script? Can we collapse the two conditional blocks into one?

[marc0der]

Ah, and of course, please refrain from using awk as this forces a hard dependency that will often not be met on very basic systems.

[reitzig]

Ah, and of course, please refrain from using awk as this forces a hard dependency that will often not be met on very basic systems.

Which systems are that? The smallest I know comes with (an) awk:

$ docker run --rm alpine awk -version
BusyBox v1.30.1 (2019-06-12 17:51:55 UTC) multi-call binary.

Of course, BusyBox binaries are quite often not compatible with GNU ones... :/

That said, which dependencies are you comfortable with? For instance, I used to use the innocuous stat but it turns out that macOS and Ubuntu come with incompatible versions (FreeBSD-ish vs GNU-ish). ls + awk was the best I could come up with -- I'm open for suggestions!

[marc0der]

The cut command is preferable as it is packaged as part of gnu coreutils. You could try something like this:

ls -ld "${SDKMAN_DIR}" | cut -d" " -f3

[reitzig]

Although I do see the point, the implementation does feel a bit hacky to me.

Do you have a proposal? I felt it's a pretty straight-forward implementation for "do we point at this user's installation?". Of course, it will fail with system installations, but IIRC that's not a use-case you support?

Can we assign this expression to a clearly named variable? Can we unset said variable at the end of the script?

Sure!

Can we collapse the two conditional blocks into one?

What do you mean? [ -z ... ] || [ ... ] into [ ... ]? No, I don't think so; [ 1 -eq 1 || 1 -eq 2 ] doesn't parse. [[ 1 -eq 1 || 1 -eq 2 ]] would work, but you use single brackets everywhere else?

[marc0der]

Actually, yes I do think so. We use double square brackets throughout the sdkman codebase when dealing with complex expressions.

[reitzig]

The cut command is preferable as it is packaged as part of gnu coreutils. You could try something like this:

ls -ld "${SDKMAN_DIR}" | cut -d" " -f3

This does fail on the current Alpine (BusyBox v1.30.1). :/

Then, maybe stat wrapped away in a function and distinguish flavors there? That's in coreutils, after all.

[reitzig]

It occurs to me that SDKMAN_VERSION is similarly affected. Is there a reason against not setting it to $(cat ${SDKMAN_DIR}/var/version), always?

[smac89]

To run a command as another user, don't use su, use sudo instead. By default, sudo will clear the current user's environment variables before starting the command.

sudo --user=<user> <cmd...>