Event Sourcing, Subscription Monitoring and Distributed Logging

[Aaron Digulla]

Hi,

I'm looking for a technology to combine microservices and crossbar.io looks very promising.

I looked at the website and have a few questions left:

1. Event Sourcing

Event Sourcing means to be able to replay all events that ever happened.

I saw that you have "Event History" which is similar to what I'm looking for but a) it's not persisted ("For the time being, memory is the only valid argument for where the store is kept,...", see https://crossbar.io/docs/Event-History/).

Is it possible to create an ordered log of all every that passed through the system?

2. Subscription Monitoring

Is it possible to monitor who is subscribed to what? Or at least to see that every subscriber has a publisher.

I'm thinking about a way to check the health of the system during development and production when it's clear what must be there for it to work. For example, if no one listens on the "send mail" event, that would be very bad in production. During development, the presence of such a subscriber would be a problem.

Is there support for analyzing the topology of the whole network of services?

3. Global Logging

When events are processed in a distributed system, we need a way to attach a token to each business operation so we can quickly collect all log entries that were generated while it ran.

Is there support for passing some token / ID around or do I have to implement this in every handler method?

Regards,

A. Digulla