Delete multiple deployments simultaneously via single kapp delete cmd

[scothis]

It would be nice to delete multiple deployment with a single command

kapp delete -a app1 -a app2 -a app3

Currently, only the last app (app3) is deleted and the others are ignored. This is common behavior with cobra, but can be surprising for users.

[cppforlife]

the alternative option is to disallow multiple -a specifications.

im not sure if we should allow multiple -a on delete as then deploy command becomes asymmetric with delete. thoughts about alternative mentioned above?

[scothis]

the alternative option is to disallow multiple -a specifications.

Cobra doesn't make this easy

[cppforlife]

can just switch to string slice type and assert on length == 1.

[scothis]

can just switch to string slice type and assert on length == 1.

The docs for the command will then be misleading as they will show the flag as an array. Also, this pattern applies to every other flag. I'd leave it alone and let Cobra manage the behavior generically.

[cppforlife]

but if so, what does it mean to kapp deploy -a foo -a another-one ...?

[cppforlife]

after thinking some more, i think at this point kapp should stick with one deployment for -a flag for now to maintain consistency with other commands.