feat: use scarf.sh registry for all container images

[mowies]

This PR

• introduces a new container registry under our own keptn domain
• this gives keptn the option to keep track of download numbers and versions of KLT that are downloaded

THIS IS A BREAKING CHANGE

Part of #195

[codecov]

Codecov Report

Merging #507 (546770f) into main (23ddfa3) will increase coverage by 0.05%.
The diff coverage is n/a.

❗ Current head 546770f differs from pull request most recent head 3b96261. Consider uploading reports for the commit 3b96261 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #507      +/-   ##
==========================================
+ Coverage   48.84%   48.90%   +0.05%     
==========================================
  Files          55       55              
  Lines        5143     5143              
==========================================
+ Hits         2512     2515       +3     
+ Misses       2525     2523       -2     
+ Partials      106      105       -1     

Impacted Files	Coverage Δ
...or/controllers/keptnworkloadinstance/controller.go	78.86% <0.00%> (ø)
...ptnworkloadinstance/reconcile_prepostdeployment.go	90.90% <0.00%> (+9.09%)	⬆️

Flag	Coverage Δ
component-tests	51.36% <ø> (+0.24%)	⬆️
keptn-lifecycle-operator	47.27% <ø> (ø)
scheduler	4.52% <ø> (ø)

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[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[hwinkel]

Any experience with the scarf service, as it might "break" the download, if not working correctly, can scarf cope with the reliability of the typical public registries?

[thschue]

lgtm

[mowies]

@hwinkel good question, we don't have any meaningful experience yet, but we aim to get it by trying scarf out for now.
It's just a proxy with a different certificate and a new DNS CNAME entry for the new domain so it should be fairly easy to run well.

[thisthat]

should we change also this: https://github.com/keptn/lifecycle-toolkit/blob/main/.github/workflows/release.yml#L57 ?

[thisthat]

Hey @hwinkel, we had a discussion with Scarf on exactly this topic and they are confident that they can handle the amount of traffic. Scarf is also used by other CNCF projects such as Linkerd which boosts our confidence in the service.

[hwinkel]

Hey @hwinkel, we had a discussion with Scarf on exactly this topic and they are confident that they can handle the amount of traffic. Scarf is also used by other CNCF projects such as Linkerd which boosts our confidence in the service.

thanks for the feeedback.. as we are looking for a similar service

[mowies]

should we change also this: main/.github/workflows/release.yml#L57 ?

@thisthat that occurrence should stay as it is. We still push to ghcr directly without going though scarf, therefore also the image tag needs to still point to ghcr.