Add cluster name to flagger cmd args for altering

[baldey-nz]

Signed-off-by: baldey-nz baldey@gmail.com

As per issue feature request #926, the notifications to slack for flagger are great but if we have multiple clusters running flagger and all are sending notifications to the same channel then its hard to determine which cluster the canary is happening in from the notification msgs.
This change adds an optional summary field (Spec.Summary)
If this fields isnt set then nothing changes in the notifications.

If summary is set then a new summary field is created e.g:

my-app.my-namespace
New Deployment detected, initialization completed.
Summary
Sandbox env
Target
Deployment/my-app.my-namespace
.......

[stefanprodan]

Please remove the cluster field and leave only summary. In a distant feature, Flagger will be integrated with Flux notification-controller and the Alert CRD from Flux contains only Summary.

[codecov-commenter]

Codecov Report

Merging #1041 (8c881ab) into main (01d4780) will increase coverage by 0.28%.
The diff coverage is 12.50%.

@@            Coverage Diff             @@
##             main    #1041      +/-   ##
==========================================
+ Coverage   56.88%   57.17%   +0.28%     
==========================================
  Files          76       76              
  Lines        6093     6169      +76     
==========================================
+ Hits         3466     3527      +61     
- Misses       2102     2111       +9     
- Partials      525      531       +6     

Impacted Files	Coverage Δ
pkg/controller/controller.go	0.72% <0.00%> (-0.01%)	⬇️
pkg/controller/events.go	52.89% <14.28%> (-2.76%)	⬇️
pkg/router/kubernetes_default.go	63.43% <0.00%> (-0.69%)	⬇️
pkg/canary/config_tracker.go	82.00% <0.00%> (-0.51%)	⬇️
pkg/router/istio.go	81.07% <0.00%> (-0.48%)	⬇️
pkg/router/util.go	100.00% <0.00%> (ø)
pkg/router/appmesh_v1beta2.go	88.12% <0.00%> (+0.30%)	⬆️
pkg/router/contour.go	88.54% <0.00%> (+0.36%)	⬆️
pkg/router/appmesh.go	85.42% <0.00%> (+0.45%)	⬆️
pkg/canary/daemonset_controller.go	58.33% <0.00%> (+0.64%)	⬆️
... and 3 more

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[baldey-nz]

Cluster field removed as requested. @stefanprodan any chance of taking another look at this one?

[Nerja]

@stefanprodan Should we maybe place the summary field in the CanaryAlert struct(

flagger/pkg/apis/flagger/v1beta1/canary.go

Line 297 in 30ab182

type CanaryAlert struct {

) instead of only providing the ability to specify a summary field per canary? Enabling the users to define a summary per alert is more in line with what is supported by the Flux Alert API.

[baldey-nz]

Hi @stefanprodan - any chance you could let us know what the preferred option is here please? we are really keen to start using flagger in production but this is currently blocking us. thanks!

[stefanprodan]

@Nerja good point, adding it to Canary means we'll break the API once we switch over to Flux notification-controller.

@baldey-nz to unblock this, I'm for adding a --cluster-name flag to Flagger, if that flag has a value, then we inject it as a cluster filed in the alert.

[baldey-nz]

@stefanprodan like this?

[stefanprodan]

LGTM

Thanks @baldey-nz