Design Patterns and Best Practices in Java

Communicating among services

Looking at the previous example, one obvious question that comes to mind is this: How would the scaled image service and thumbnail service be triggered? Well, there are many options. The most common ones are REST-based communication, where the upload service can make a REST call to the other two services, or message queue-based communication, where the upload service would add a message to the queue that can be processed by other services, or a state-based workflow, where the upload service will set a state in the database (for example, ready for scaling) that will be read by other services and processed.

Based on the application needs, you can take a call as to which communication method is preferred.