Update KEDA ScaledObject API to include MetricType for Triggers

[vidhartbhatia]

I apologize if I missed anything, but I wanted to initiate this PR to try and fix the KEDA scaled object issue where the trigger metric type isn't copied over correctly, I suspected it was just due to the API being out of date

I will update as needed, any advice is welcome!

[vidhartbhatia]

Sorry forgot to link it to the issue, this is intended to fix #1240

[vidhartbhatia]

For reference this is the latest API i copied over: https://github.com/kedacore/keda/blob/main/apis/keda/v1alpha1/scaledobject_types.go

[aryan9600]

Hi @vidhartbhatia, thanks for catching the issue and opening this PR!

[vidhartbhatia]

Hey, @aryan9600 I noticed another issue, it's not strictly related but I figure if you think of a small fix we can include it in this PR.
Basically, when we switch from using scaled object to hpa and vice versa in the canary spec, the old primary resource gets left behind, It would be great to have flagger delete the old -primary hpa or scaledobject when a deployment happens.

Here you can see the state after each deploy, this would casue issues as keda and hpa dont behave well together:

Update: We just worked around this by running a clean up script so no rush on it

[aryan9600]

@vidhartbhatia Yes, that'd be ideal (ref: #259), but the fix won't be small enough for it to be included in this PR. If you'd like to give it a shot, please feel free to open another PR for this :D

[vidhartbhatia]

@vidhartbhatia Yes, that'd be ideal (ref: #259), but the fix won't be small enough for it to be included in this PR. If you'd like to give it a shot, please feel free to open another PR for this :D

@aryan9600 Okay that makes sense! for now then we really need this current bug fix in asap so we can take KEDA to production so Any help getting this through and merged and then a minor release would be appreciated!
@stefanprodan I noticed you were also requested as a review, just wanted to bump :)

[stefanprodan]

This is a breaking change in Keda API, usually you never remove fields without bumping the API version, instead you mark them as deprecated. Due to this, we need to update the Keda doc with the exact version which Flagger expects.

[stefanprodan]

LGTM

Thanks @vidhartbhatia and @aryan9600

stale