Passing MetaData beween User Defined Code

[RohanAshar]

Summary

We need a mechanism to pass metadata between user defined code. We have a usecase where we want to use Numaflow monovertex to route between multiple kafka topics. We have a transformer that has the business logic to determine the route but we dont have a way to pass that information to sink to actually route it. We thought about using headers but as they are immutable we cant use that.

As a stop gap we are using keys to propagate this info.

Use Cases

When would you use this?

---

Message from the maintainers:

If you wish to see this enhancement implemented please add a 👍 reaction to this issue! We often sort issues this way to know what to prioritize.