Implementing the Sidecar Pattern in Microservices-based ASP.NET Core Applications

A step-by-step guide to implementing the sidecar design pattern in ASP.NET Core microservices. The tutorial builds an inventory management system with two services: a TransactionsAPI that generates logs and a SidecarAPI that reads those logs from a shared file system and forwards them to Elasticsearch. Covers creating thread-safe file loggers, background services, concurrent queues, Docker and Docker Compose configuration, and discusses alternatives like Dapr, Serilog, and Kubernetes pods. Also addresses performance considerations such as batching Elasticsearch writes and using in-memory caching to avoid duplicate log entries.