Orchestration vs. choreography

Image CC BY-SA 2.0, hernanpc

This has been earlier published in Medium

Technology nowadays starts to be mature enough for microservices to be adopted by mainstream developers. Containerization, provisioning and build automation tools make it easy to create new services quickly. Focal points for these services are agility in transformation and manageability as microservices have clear responsibilities.

Traditional software mixes multitude of responsibilities and features together and makes it harder to make changes without breaking something in the process. Microservices tackle this by separating functionality to smaller pieces that are easy to test and manage.

What this trending shift from traditional software to microservices mean in organisational context is more agile and faster development, simpler services with clear responsibilities and a new way of managing and producing services. However microservices are not a silver bullet that kills the complexity. Actually microservices come with all the complexity that distributed systems have.

Slicing software to a big set of smaller services has huge impact to integration architecture. Traditional orchestrated ESB driven architecture starts to slow down the agility and idea of microservices quite fast. As a centralized solution ESB becomes a bottleneck when it tries to abstract and connect hundreds of microservices together in a fast, changing environment.

Integration architectures with ESB based solution made it easy to manage interactions between traditional software systems and leverage the power of business processes. This way there is no direct connections between systems and interfaces and communication methods can be abstracted.

However centralized integration solutions mean centralized management and changes when there is new or changing requirements. This wouldn’t be a problem with traditional systems but with microservices changes happen more often as the building blocks are much smaller than with larger systems.

With microservices integration architecture needs a new point of view. Rapid and lean development accompanied with automated build processes cut down costs attached to changes.

I think that integration architecture with microservices should also adapt to the idea of smart services and dump (data)pipelines.

Nic Ferrier has a great piece of writing about this.

Integration architecture with value added services would be more about designing communication patterns with event driven messaging, aggregating and managing events to form clear view to operative processes and providing services like API management to support businesses.

It’s clear that current integration practices do not blend well with microservice ideology but it takes time for microservices to become mainstream. Being extreme SOA microservices require new ways of thinking to make them manageable in long run.