Add sink resources

[wfernandes]

This PR is intended to initiate conversation around adding sink resources to observability. We have attempted to follow knative conventions/guidelines as much as possible.

We are looking for feedback.

Summary of the changes:

• Add sink resources config
• Add sink and event controllers
• Add tests for sink-resources CRDs
• Add test infra
• Add e2e tests
• Add CONTRIBUTING guidelines for development
• Move role bindings to separate files and make file names consistent
• Fix fluent bit labels
• Pin fluent-bit-out-syslog version to v0.9
• Update imagePullPolicy to IfNotPresent for fluent-bit-out-syslog
• Refactor signal handling to use knative/pkg/signals
• Modify controllers to implement cache.ResourceEventHandler interface
  https://godoc.org/k8s.io/client-go/tools/cache#ResourceEventHandler
• Pin version of oratos/crosstalk-receiver in e2e tests to v0.3
• Pin version of ubuntu to Xenial in e2e tests. Xenial is currently OSL approved.

[googlebot]

So there's good news and bad news.

👍 The good news is that everyone that needs to sign a CLA (the pull request submitter and all commit authors) have done so. Everything is all good there.

😕 The bad news is that it appears that one or more commits were authored or co-authored by someone other than the pull request submitter. We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that here in the pull request.

Note to project maintainer: This is a terminal state, meaning the cla/google commit status will not change from this state. It's up to you to confirm consent of all the commit author(s), set the cla label to yes (if enabled on your project), and then merge this pull request when appropriate.

[jasonkeene]

As far as the google bot is concerned. I am the author of the commits and I confirm that I am ok with these commits being contributed to the project. I can not set the cla label to yes so I leave that up to the powers that be.

This is a large change. It is most of the work that we have put into the sink resources. This is just a first stab at getting this functionality into knative. There has been suggestions that we consider using the knative/pkg/controller for our controllers, however that isn't within the scope of this initial PR.

We'd appreciate any feedback on this change.

[dprotaso]

/assign @dprotaso

[yanweiguo]

cc @mdemirhan

[googlebot]

CLAs look good, thanks!

[mdemirhan]

This one is too big to to a proper review. Should we check this in and provide feedback in an async manner?

[jasonkeene]

@mdemirhan We'd be fine with that. Additionally, @dprotaso asked to separate out the vendor/ dir into its own commit to make it easier to review the actual content of the change. You can view the actual changes here:

e28485b

[jasonkeene]

/lgtm

[jasonkeene]

/approve

[jasonkeene]

Something to be aware of is that the CRDs we originally created were targeted towards using syslog only. As a result we were able to do some custom validation on fields such as host/port:

https://github.com/knative/observability/pull/2/files#diff-135361e4eaf0dcd19d26d6aecc6209b1

This might have to go away when we end up supporting other output types. I imagine elasticsearch and stackdriver are two types we'd want to support shortly. Other types might have different configuration than host, port, enable_tls and insecure_skip_verify. I've put some thought into different structures for the LogSink CRDs that we might want to use but I really like the simplicity of what we currently have.

Any thoughts/feedback on the CRDs alone?

cc/ @dprotaso @mdemirhan

[googlebot]

So there's good news and bad news.

👍 The good news is that everyone that needs to sign a CLA (the pull request submitter and all commit authors) have done so. Everything is all good there.

😕 The bad news is that it appears that one or more commits were authored or co-authored by someone other than the pull request submitter. We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that here in the pull request.

Note to project maintainer: This is a terminal state, meaning the cla/google commit status will not change from this state. It's up to you to confirm consent of all the commit author(s), set the cla label to yes (if enabled on your project), and then merge this pull request when appropriate.

[jasonkeene]

As far as the google bot is concerned. I am the author of the new commit and I confirm that I am ok with this commit being contributed to the project.

Not sure how to prevent cla/google from complaining when we push changes in the future.

[dprotaso]

Take a look at my comments and let me know if you have any questions!

[wfernandes]

@dprotaso I removed the priorityClassName from the fluent-bit daemonset manifest. We had that in there because we copied it from another fluent-bit k8s manifest. I believe this is the same action taken by knative/serving.

[Benjamintf1]

/lgtm
/approve

[Benjamintf1]

Does it think jason or I don't approve of our commits being in this project? Can anyone fix this check?

[googlebot]

CLAs look good, thanks!

[Benjamintf1]

/lgtm
/approve

[Benjamintf1]

/approve

[knative-prow-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Benjamintf1, jasonkeene, wfernandes

The full list of commands accepted by this bot can be found here.

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• OWNERS [Benjamintf1,jasonkeene,wfernandes]

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