feat: Support dataTemplate and contextTemplate for Trigger Parameters

[tinyzimmer]

This PR relates to the issue I opened: #541

One thing I am definitely open to maybe doing is maybe a number on ResolveParamValue. With the two additions it feels like it's getting a bit unruly.

I can add some coverage as well. So consider this just a WIP to get feedback on the approach.

As a side note, I am having trouble running make codegen

./hack/update-api-docs.sh
I0315 18:03:19.811707    6828 main.go:127] parsing go packages in directory github.com/argoproj/argo-events/pkg/apis/eventsources/v1alpha1
F0315 18:03:21.224675    6828 main.go:133] no API packages found in github.com/argoproj/argo-events/pkg/apis/eventsources/v1alpha1

But that doesn't seem right...

[CLAassistant]

All committers have signed the CLA.

[VaibhavPage]

Thanks for the PR. This feature is awesome!! Just a couple of suggestions,

1. You may need to run make codegen and commit updated files for deep copy and api docs.
2. Can you also add an example sensor YAML file under examples/sensors folder that demonstrates the templating functionality?

[tinyzimmer]

1. You may need to run make codegen and commit updated files for deep copy and api docs.

I feel like an idiot, but I'm still struggling with this. On my mac it gives the error I showed above once it's done allegedly running deep copy funcs (that dont produce any changes).

Tried on Linux, and it ran all the way through, but again didn't actually generate any deep-copy code, and for the html/md files it just converted every kind to it's full path...e.g.

-<code>context</code></br> <em> Argo Events common.EventContext </em>
+<code>event</code></br> <em>
+github.com/argoproj/argo-events/pkg/apis/common.Event </em>

This is beginning to make me doubt my sanity.

2. Can you also add an example sensor YAML file under examples/sensors folder that demonstrates the templating functionality?

I will add an example if not tonight, then sometime in the morning.

[VaibhavPage]

Changes look good to me. I'll fix the make codegen part.

[tinyzimmer]

Changes look good to me. I'll fix the make codegen part.

I'd be very curious what the issue was in case I want to contribute more in the future 😄

[VaibhavPage]

As you have introduced string fields within an existing struct, the deep-copy script won't update anything. But, make codegen should at least update API docs under api folder and openapi_generated.go file. make codegen really just runs 1) https://github.com/argoproj/argo-events/blob/master/hack/update-codegen.sh 2) https://github.com/argoproj/argo-events/blob/master/hack/update-openapigen.sh and 3) https://github.com/argoproj/argo-events/blob/master/hack/update-api-docs.sh under the hood. So, you can run these files individually as well.

[VaibhavPage]

Also, can you resolve the conflicts? Thanks.