Cross linking of event fields.

[donaldpipowitch]

Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Description

It would be lovely if we could link/reference from one event field to the field of a different event. Speaking about this view here:

Motivation

Imagine you have TradeCreated event with the two fields buyerId and sellerId. It would be lovely if both fields could link/reference to an id field in a UserCreated event. That way people can jump to UserCreated and from here on check related fields or other related events.

This feature request is not exactly about supporting $ref in JSON Schemas. As far as I know $ref references a complete (sub)-schema. If TradeCreated: buyerId and TradeCreated: sellerId would reference UserCreated: id directly they would inherit the description of UserCreated: id and could not provide there own. (But I might be wrong here.) So I'd still like to be able to write something like this:

UserCreated:
  properties:
    id:
      description: "Use this to reference any user."

TradeCreated:
  properties:
    buyerId:
      description: "References a user which has money and trades it for some goods."
    sellerId:
      description: "References a user which offers goods."

I wonder what would be the best way to support? Currently I could imagine two weeks:

• extend JSON Schema somehow (misusing fields like $comment or adding custom fields)
• provide an additional EventCatalog-specific document (something like a sitemap.xml, but for events)

In case of an EventCatalog-specific document it would be nice if we could design it in a way that it can be extended in the future. E.g. another feature we'd love to see would be placing events in "business process flows. E.g. something like this:

TradeRequested ----- TradeAccepted ----- TradeDelivered
               \
                 --- TradeRejected