ReactiveSocket metrics stream

[robertroeser]

Metrics stream implementation in reactive sockets. Takes a 32-bit integer that represents the stream type. Data is streamed as CBOR.

[mattrjacobs]

Typo: Collasper -> Collapser

[mattrjacobs]

A couple more questions:

1. How should this actually get exposed over the network? As an example, if I wanted to use this for hystrix-examples-webapp, I could set up a EventStreamRequestHandler. From that, I can get a Publisher<Payload> by passing in the appropriate enum. But I'm not familiar enough with ReactiveSocket to know how to expose that, and then set up a client on the other side.

2. The code to convert data types into JSON/CBOR is very similar to hystrix-metric-event-stream. Would it make sense to directly expose a map-like object from hystrix-core, on the assumption that any serializer wants that? If that were exposed, then any given serializer wouldn't care anything about the content of the data, just the field-types.

[robertroeser]

1) How should this actually get exposed over the network? As an example, if I wanted to use this for hystrix-examples-webapp, I could set up a EventStreamRequestHandler. From that, I can get a Publisher by passing in the appropriate enum. But I'm not familiar enough with ReactiveSocket to know how to expose that, and then set up a client on the other side.

EventStreamRequestHandler is roughly equivalent to a HttpServlet. When you create an instance of a ReactiveSocket you would give it an instance of this class.

2) The code to convert data types into JSON/CBOR is very similar to hystrix-metric-event-stream. Would it make sense to directly expose a map-like object from hystrix-core, on the assumption that any serializer wants that? If that were exposed, then any given serializer wouldn't care anything about the content of the data, just the field-types.
Sure - add a method on the Metrics objets that gets the metrics as a map?

[mattrjacobs]

Merging this, and I'll work on building a client and the data type work outlined in my second point above. Thanks @robertroeser !