Microservices Development Cookbook

How to do it...

Migrating data from a monolith database to a new store fronted by a new service, without any impact on availability or consistency, is a difficult but common task when making the transition to microservices. Using our fictional photo-messaging application, we can imagine a scenario where we want to create a new microservice responsible for handling media uploads. In this scenario, we'd follow a common dual-writing pattern:

1. Before writing a new service to handle media uploads, we'll assume that the monolith architecture looks something like the following diagram, where HTTP requests are being handled by the monolith, which presumably reads the multipart/form-encoded content body as a binary object and stores the file in a ...