Go Runtime with go mod

[thspinto]

☕ Purpose

Implement Go runtime with go mod as dependency manager.

❓ Questions

• Should we create a new runtime for go due to breaking changes?
• I used golang as name for the run time, but not sure if it is the best name.
• Where to host the official docker image?

🧐 Checklist

• Add CI integration
• Send to stable dir

🍩 Further details

Let me know what you think of this PR, I'll finish de CI integration after discussing the questions.

[thspinto]

Related Issues

• Update settings for Golang kubeless#1136
• Golang modules support kubeless#1100
• Support for Go Modules #70

[andresmgot]

Thank you for the PR @thspinto! It's looking good so far :)

So, regarding how to handle the breaking change, ideally I would maintain support for the old runtimes (go1.12, go1.11...) and use go dep with those but it's true that is not currently supported by Kubeless core.

Since we are not actively adding new features to Kubeless core I think it's better to just replace the current go runtimes with go1.13 and go1.14 to avoid confusion and use go.mod instead. When releasing a new version of Kubeless we can notify people of the breaking change in go and add some instructions to use the latest version of Kubeless with the old version of the runtimes in case is necessary.

Regarding the image registry, once the PR is ready, I will build the golang images and update the jsonnet manifest to point to kubeless/go.....

Hope that makes sense to you!

[thspinto]

Hope that makes sense to you!

It does. I'm going to fix the tests and add the instructions to run the legacy version then.

Thanks @andresmgot.

[thspinto]

Done. Ready for review.

[andresmgot]

Sorry for the late response @thspinto! (I've been out of the office for a while). It seems that you copied the same jsonnet file twice :) Apart from that, the rest looks good to me, I will build the images once that is ready.

[andresmgot]

this file should contain the runtimes for go1.10, go1.11 and go1.12 :)

[thspinto]

Lol. Missed that, thanks =).

[andresmgot]

Thanks for the changes! Do you mind updating the kubeless docs with the new changes here: https://github.com/kubeless/kubeless/blob/master/docs/runtimes.md#go?

[thspinto]

Thanks for the changes! Do you mind updating the kubeless docs with the new changes here: https://github.com/kubeless/kubeless/blob/master/docs/runtimes.md#go?

Sure, I'll send a PR over there! Thanks!