feat: update to terraform-plugin-sdk2

[mavogel]

• see Update to SDK v2 hashicorp/terraform-provider-docker#310
• https://www.terraform.io/docs/extend/guides/v2-upgrade-guide.html

[mavogel]

Currently, trying to fix

tf-sdk-migrator v2upgrade --sdk-version v2.4.0
Rewriting provider go.mod file...
Rewriting SDK package imports...
Running `go mod tidy`...
Error running go mod tidy: exit status 1
go: github.com/hashicorp/terraform-plugin-sdk/[email protected] requires
        cloud.google.com/[email protected] requires
        github.com/google/martian/[email protected] requires
        golang.org/x/[email protected]/go.mod: verifying module: golang.org/x/[email protected]/go.mod: cannot authenticate record data in server response

@innovate-invent, did you have something similar in #23 ?

[innovate-invent]

I did not, it looks like the hash of the module is not matching what it is expecting.
I should point out that in my PR I have many manual changes that are required for the update.

[mavogel]

Ok thanks for the heads-up. Do you need any support on the PR from my side @innovate-invent ? I'd like to push this one forward :)

[innovate-invent]

Do you mind taking over the PR? It looks like the original repo and yours have diverged a bit

[mavogel]

Sure thing. Thanks for the initial work. First I need to get the issue mentioned above to be fixed

[innovate-invent]

try and delete the go.sum file?

[mavogel]

tried deleting go.sum, but it did not help 😕

• I had a similar issue with golang.org/x/oauth2 which I could solve with go get golang.org/x/[email protected], but for golang.org/x/net it does not work...
• I also tried export GOPROXY=https://gocenter.io,https://proxy.golang.org,direct, which did not help either

[innovate-invent]

perhaps add

replace github.com/google/martian/[email protected] => github.com/google/martian/[email protected]

to your go.mod?

also try go clean -modcache if you haven't already

[mavogel]

go clean -modcache was the key :) Thx. Feels like I need to dig a bit deeper into those modules to understand the process.
Now I can continue at least.