Use go-homedir.Dir() everywhere

[kim0]

This can also close #117 since the binary will now respect $HOME which can be set to any location instead of ~/.terraform.versions

[yermulnik]

Hey @kim0
Thank you for the contribution. I have two questions:

1. I'm not quite really familiar with Golang internals and hence why is so huge removal change set for go.sum file?
2. Looking at description and code of os.UserHomeDir(), I can see it relies upon HOME env var exclusively and returns error if it is not defined, which is quite rare though still viable condition (when HOME env var (or non-Linux OS alternative) is not defined), whilst go-homedir does its best to dig to the bottom of it and (despite running external commands) tries to determine user home dir much better than os.UserHomeDir() — what's the rationale behind this PR given the comparison on how these two determine user home dir? Thanks (and sorry if the question is dumb — I'm not a Golang folk 🤷🏻)

ps: this PR may also become stale as both owner (@warrensbox) and another contributor (@jukie) are more of not with this project rather than with it 😢

[kim0]

Hello @yermulnik

Thanks a lot for your feedback. I'm not that great with Golang either, I didn't think os.UserHomeDir() only looks at the HOME env var, but looking at its code, that does seem to be the case! A bit surprising since that is supposed to be the recommended way to work. Anyway, for now, I've switched everything to use go-homedir which does seem to do a better job!

It's sorta sad that the maintainers are no longer active mostly. My use-case involves running tfswitch with a read-only home directory on AWS lambda, which causes errors since tfswitch insists on writing to the home directory and does not respect $HOME. I hope I don't end up forking this repo and building releases! Really hope the maintainers can get in touch soon. Thanks!

[yermulnik]

My use-case involves running tfswitch with a read-only home directory on AWS lambda, which causes errors since tfswitch insists on writing to the home directory and does not respect $HOME.

Would the https://github.com/warrensbox/terraform-switcher#use-tfswitchtoml-file--for-non-admin---users-with-limited-privilege-on-their-computers be an option for your use case? You also can provide binary path as command line arg.

I hope I don't end up forking this repo and building releases! Really hope the maintainers can get in touch soon. Thanks!

🤞🏻

[kim0]

be an option for your use case?

Thanks a lot for the reply @yermulnik .. wrt the suggested tfswitch -b or conf file, unfortunately this does not help. This is bec tfswitch is very stubborn wanting to write to the home directory. This was the reason for this PR. I confirmed -b doesn't help, by running in a container with the home directory /root mounted as read-only. You can see it fail below

root@5bc5fcb6879a:~# pwd
/root
root@5bc5fcb6879a:~# touch foo
touch: cannot touch 'foo': Read-only file system
root@5bc5fcb6879a:~# tfswitch -u -b /tmp/terraform
Creating directory for terraform binary at: /root/.terraform.versions
Unable to create directory for terraform binary at: /root/.terraform.versionspanic: mkdir /root/.terraform.versions: read-only file system

goroutine 1 [running]:
github.com/warrensbox/terraform-switcher/lib.CreateDirIfNotExist({0xc000327300, 0x19})
        /home/circleci/go/src/github.com/warrensbox/terraform-switcher/lib/files.go:112 +0x147
github.com/warrensbox/terraform-switcher/lib.GetInstallLocation()
        /home/circleci/go/src/github.com/warrensbox/terraform-switcher/lib/install.go:72 +0xca
github.com/warrensbox/terraform-switcher/lib.Install({0xc000300651, 0x5}, {0x7ffdda050f10?, 0xc0000920f0?}, {0x9e004d, 0x28})
        /home/circleci/go/src/github.com/warrensbox/terraform-switcher/lib/install.go:94 +0x70
main.installLatestVersion(0xc00016acb0, 0xc00016ad90)
        /home/circleci/go/src/github.com/warrensbox/terraform-switcher/main.go:237 +0x50
main.main()
        /home/circleci/go/src/github.com/warrensbox/terraform-switcher/main.go:179 +0xc9f
root@5bc5fcb6879a:~# echo $?
2
root@5bc5fcb6879a:~# ls -l /tmp/terraform
ls: cannot access '/tmp/terraform': No such file or directory

So given this failure, are you interested in merging this PR please? Let me know, thanks!

[kim0]

Sorry @yermulnik I confused you with being a maintainer .. Guess I'll have to wait more or find some other solution