Auto create events in channels

[Cali0707]

Fixes #7044

Proposed Changes

• Refactor eventtypes.go and eventtypes_test.go out of the broker package into their own package to facilitate sharing code with channels.
• Use the auto create funcionality from the eventtypes package in the fanout message handler to autocreate event types.

Pre-review Checklist

• At least 80% unit test coverage
• E2E tests for any new behavior
• Docs PR for any user-facing impact
• Spec PR for any new API feature
• Conformance test for any change to the spec

Release Note

Even Type auto-create feature:
- Based on CloudEvents processed in an inmemorychannel corresponding `EventType` resources are created in the namespace  

Docs

Tracking issue for docs: knative/docs#5612

[knative-prow]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[codecov]

Codecov Report

Patch coverage: 32.05% and project coverage change: -0.30% ⚠️

Comparison is base (ed05a35) 78.29% compared to head (115461e) 77.99%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7089      +/-   ##
==========================================
- Coverage   78.29%   77.99%   -0.30%     
==========================================
  Files         250      250              
  Lines       13290    13367      +77     
==========================================
+ Hits        10405    10426      +21     
- Misses       2353     2405      +52     
- Partials      532      536       +4     

Files Changed	Coverage Δ
pkg/broker/ingress/ingress_handler.go	60.09% <ø> (ø)
pkg/channel/fanout/fanout_message_handler.go	74.66% <21.42%> (-12.64%)	⬇️
...iler/inmemorychannel/dispatcher/inmemorychannel.go	65.19% <31.03%> (-6.52%)	⬇️
...nnelfanout/multi_channel_fanout_message_handler.go	86.88% <100.00%> (ø)
pkg/eventtype/eventtypes.go	72.22% <100.00%> (ø)
...econciler/inmemorychannel/dispatcher/controller.go	81.73% <100.00%> (+0.83%)	⬆️

... and 8 files with indirect coverage changes

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[Cali0707]

@creydr @pierDipi I'm getting the following error when running the InMemoryChannel after making my changes:

k8s.io/client-go@v0.26.5/tools/cache/reflector.go:169: Failed to watch *v1beta2.EventType: failed to list *v1beta2.EventType: eventtypes.eventing.knative.dev is forbidden: User "system:serviceaccount:knative-eventing:imc-dispatcher" cannot list resource "eventtypes" in API group "eventing.knative.dev" at the cluster scope

Any ideas what I should do?

[creydr]

@creydr @pierDipi I'm getting the following error when running the InMemoryChannel after making my changes:

k8s.io/client-go@v0.26.5/tools/cache/reflector.go:169: Failed to watch *v1beta2.EventType: failed to list *v1beta2.EventType: eventtypes.eventing.knative.dev is forbidden: User "system:serviceaccount:knative-eventing:imc-dispatcher" cannot list resource "eventtypes" in API group "eventing.knative.dev" at the cluster scope

Any ideas what I should do?

Hey @Cali0707,
it seems the imc-dispatcher user does not have permissions to list EventTypes. The config/channels/in-memory-channel/roles/dispatcher-clusterrole.yaml file defines the rules for this user. So you need to add the required permissions there too.

[Cali0707]

/hold
This needs #7091 to be resolved before it will work

[Cali0707]

This is now working for me:

kn-event-linux-amd64 send \                                                                                      
--to Channel:messaging.knative.dev/v1:example-channel \
--type org.test.message.error \
-f message="There is a problem"

kn-event-linux-amd64 send \                   
--to Channel:messaging.knative.dev/v1:example-channel \
--type com.company.test.warning \
-f message="There is a problem"

kubectl get eventtypes.eventing.knative.dev -A
NAMESPACE   NAME                            TYPE                       SOURCE             SCHEMA   REFERENCE NAME    REFERENCE KIND    DESCRIPTION                             READY   REASON
default     et-example-channel-b3jnlnrlc3   org.test.message.error     kn-event/v1.10.0            example-channel   InMemoryChannel   Event Type auto-created by controller   True    
default     et-example-channel-y29tlmnvbx   com.company.test.warning   kn-event/v1.10.0            example-channel   InMemoryChannel   Event Type auto-created by controller   True    

[Cali0707]

Note: I had to change how the eventtype names are autogenerated because they were not unique enough. With the old function, I could only get one unique event name per channel/namespace pair. With the new function, I can get unique event names if the event type is different enough (e.g. org.test.message.error vs. com.company.test.warning), but if they are too similar then it still has issues. I will open a new issue to fix that as it isn't directly related to these changes

[Cali0707]

/unhold

[matzew]

nice to move that out

[matzew]

/lgtm
/approve

[knative-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Cali0707, matzew

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