Grpc

Every public-facing API in the Composable Commerce Platform starts as a .proto file. The code — Go gRPC handlers, TypeScript SDK, HTTP routes, request validation, error codes — is generated from that contract. This article documents the conventions that make that system work. Answer-first: Internal services communicate via gRPC (type-safe, binary, ~7× faster than JSON over REST). External clients (browser, mobile app) use REST via the Gateway Service (port 8000). The proto file is the single source of truth for the API contract — and three proto conventions require special attention for engineers coming from Magento: the Money type (never use float for prices), cursor-based pagination (never use offset), and proto-level field validation (validation declared in the contract, not in business logic). ...

Answer-first: gRPC is optimized for internal microservices using binary Protobuf serialization over multiplexed HTTP/2 or HTTP/3 streams. REST uses standard JSON over HTTP/1.1 or HTTP/2, serving as the default for public APIs. GraphQL operates as an aggregator at the API gateway or Backend-for-Frontend (BFF) layer, allowing clients to query specific properties, but requires complexity limits and DataLoader batching to prevent server degradation. Prerequisite: This is Part 12 of the System Design Masterclass. Previous parts built the reliability patterns — this part covers comparing communication protocols and data formats for microservice communication. ...

← Series hub ← Prev • Next → Prerequisite: Ensure you have read Part 3: Spatial Indexing (Uber H3, PostGIS & Redis GEO) before integrating with Golang microservices. Building a simple API that calls Graphhopper via http.Get is easy. Building a Principal-level API Gateway that survives 10,000 concurrent riders requesting routes without crashing is a masterclass in Distributed Systems. Answer-first: Graphhopper is a heavily CPU-bound downstream service. If your Golang API blindly accepts traffic and forwards it, a slight slowdown in Graphhopper will cause your Goroutines to pile up, exhausting your server’s RAM and triggering a cascading failure. You must implement a “Defense in Depth” strategy using Concurrency Bounding, Circuit Breakers, and Asynchronous Pub/Sub. ...

Answer-first: Optimize inter-service communication in Go microservices using gRPC and Protobuf, delivering 3-10× smaller payloads and sub-millisecond latencies compared to REST. Secure communication channels with mutual TLS (mTLS), handle cross-cutting concerns using custom interceptor middleware, and implement native gRPC health checking for container readiness probes. What You’ll Learn That AI Won’t Tell You Optimizing Protobuf serialization overhead in Go-based gRPC microservices. How to set up connection keep-alive parameters to prevent TCP connection drops during peak load. Why gRPC for Go Microservices? The key advantages over REST: ...