Service Collaboration

The recent trend in application architectures is to transition from monolithic applications to a microservices model. Software development teams are trying to develop a unified architecture that will work for most of the use cases in real world applications: online transactional, batch, IoT and big data processing pipelines.

This transition without a good service interaction model will most likely result in chaos and a service landscape that’s hard to govern and maintain.The teams would have hundreds of microservices communicating with each other without any governance to allow only the authorized microservices to call the other microservices.

The following article is to discuss the pros and cons of service orchestration vs. service choreography and best practices on how to implement business process services that require calling multiple microservices.

Let’s assume you want to build a simple order system covering the whole order fulfillment process with the following three microservices involved:

• Payment
• Inventory
• Shipping

The overall order fulfillment definitely requires these three services to collaborate. Currently there is a big fight going on as to which collaboration style to use — orchestration or choreography (for an introduction on the basic styles see Orchestration or Choreography).