Turn packages into modules for independent versioning

[ian-shim]

Right now, the entire repository is versioned together.
If there is a desired patch for one package, but that version has an undesired update on another package, I cannot make an upgrade.
Ideally, each package is versioned separately, so that developers can upgrade specific packages.

[afkbyte]

Hey! Would you want a go.work at root or something to generate a go.work including each of the modules?

This discussion for reference: golang/go#53502

[samlaf]

Good find @afkbyte . Didn't read through the whole issue, still confused as to what exactly is happening with the go.work file. The last message (golang/go#53502 (comment)) is saying it's needed for vscode to be able to identify the different go.mod files in the repo.

Not sure what the exact tradeoffs he's mentioning are, aka what's wrong with checking the go.work file into the repo. Are you aware of this @ian-shim ?

[samlaf]

Coming back to this super old issue because I just randomly got more context on how golang does packaging/moduling/versioning.

Basically in golang modules are the unit of versioning: packages cannot be independently versioned. So I updated the title to reflect that this requires moving to modules.

Now as to whether we want to use a go.work or not, I think that is an independent question. That issue was closed and the main https://go.dev/ref/mod#workspaces updated with a recommendation to NOT commit the go.work (not sure about that vscode issue though):

From reading https://go.dev/blog/get-familiar-with-workspaces, it seems like go workspaces are more of a devex tool to help develop different modules together without having to go add replace directives in all of their respective go.mod files. So basically you can spin up go workspaces as you wish, just for development purposes. But if our modules in the sdk don't have that many dependencies, then we don't even need to use workspaces, we can just while developing go add some replace directives.

The aws sdk is an example of a multi-module repo that doesn't have a go.work checked in: https://github.com/search?q=repo%3Aaws%2Faws-sdk-go-v2%20go.mod&type=code

[shrimalmadhur]

I like the idea of breaking into modules. Rust sdk has similar models of crates. This might also help in defining better interface between modules and push us not to break.