wardlem / sialia.jl

A microservices framework for building web applications

Sialia

sialia.jl's Issues

Event Store

Summary

Events need to be transactionally stored in a persistent data store. Eventually, this will be done through an interface or abstract type, but for now, a default implementation should be created. Likely, the initial implementation will be based on MongoDB to keep the required infrastructure to a minimal level.

Details

An event record will require the following fields:

• Context
• Event Type (scoped to the context)
• Event Id (guid?)
• Aggregate (aggregate type, optional)
• Aggregate Id (only if aggregate exists)
• Aggregate Version (for optimistic concurrency control)
• Data Mime (The format the data is stored in)
• Data (serialized, binary value)
• Timestamp
• Correlation Id

Future work

• Add support for encrypting an event's data at rest (to protect sensitive data)
• Automatic snapshots of aggregates

Event Broker

Summary

Sialia needs an event broker to distribute messages to services.

Eventually, this will be done through an abstract type or interface in order to swap out the broker implementation, but for the initial implementation, a broker built on Redis streams will be Implemented.

Aggregates

Summary

An aggregate is a projection of past events utilized to perform logic related to rejecting or accepting a command. An aggregate must be able to perform the following:

• Reconstruct its state from events
• Handle command logic

Details

Implement this as an abstract type with a defined interface.