Revert environment regexp in opts

[vdemeester]

Remove the environment regexp introduced in #13694 as it makes some application not working anymore.

As said in #16585

Environment variable names used by the utilities in the Shell and Utilities volume of IEEE Std 1003.1-2001 consist solely of uppercase letters, digits, and the '_' (underscore) from the characters defined in Portable Character Set and do not begin with a digit. Other characters may be permitted by an implementation; applications shall tolerate the presence of such names. Uppercase and lowercase letters shall retain their unique identities and shall not be folded together. The name space of environment variable names containing lowercase letters is reserved for applications.

Even if I was liking this, as @tianon said, docker should be tolerant on the environment passed as is — separation of concern, it's up to the application to handle this or not 😅.

The only question I have on that one is the fact that ParseEnvFile behave differently from ValidateEnv as it checks from white spaces where the other don't. What should we do there ?

Fixes #16585

Signed-off-by: Vincent Demeester vincent@sbr.pm

[thaJeztah]

Perhaps you should add some of the discussion in this PR (and the linked issue) in a comment (and in the commit message) to explain why we're not validating that the characters are valid for environment vars. (also to prevent someone to re-introduce the regex in future)

[vdemeester]

@thaJeztah true 😝

[vdemeester]

and done :)

[vdemeester]

/ping @calavera @duglin

[phemmer]

why trim whitespace? It's technically allowed to have an env var with leading whitespace.

[vdemeester]

@phemmer it's how it was done before the regexp so I reverted to it. But yeah.. and in ValidateEnv we do not trim leading space so.. there is something to do.. (probably removing this trim)

[calavera]

let's leave this here. I'd rather have the previous behavior, that seemed to work as expected, than a new different behavior.

[calavera]

@vdemeester can we add a couple new regression tests to opts/envfile_test.go with special characters, like . and _ to make sure this doesn't break again?

[vdemeester]

@calavera yes, will do 😉.

[vdemeester]

@calavera done 😉

[calavera]

LGTM

[LK4D4]

LGTM