gRPC vs REST APIs - Key Differences

The article compares two popular API frameworks, REST and gRPC, highlighting their benefits, limitations, and potential use-cases. REST APIs are widely adopted in modern web development for building stateless, scalable, and reliable APIs. They rely on HTTP verbs to perform CRUD operations and follow design constraints such as uniform interface, decoupling the client and server, stateless interface, cacheability, layered architecture, and code on demand. On the other hand, gRPC is a universal, open-source, high-performance RPC framework that enforces scalability and performance for microservice architecture. It uses function calls to enforce client-server communication in microservices built with different programming languages and relies on protocol buffers (protobufs), streaming, and the HTTP/2 protocol for message transmission. gRPC APIs are modeled as a resource hierarchy and follow design constraints such as resource & service-oriented design, open-source, layered architecture, payload agnostic, flow control, metadata exchange, extensions as APIs, standard status codes. The article concludes by stating that both REST and gRPC API design models provide a way to connect loosely-coupled services in modern software development. While REST APIs are best suited for applications requiring high-speed HTTP message transfer iteration and cloud applications with flexible changes in workload, gRPC is ideal for building internal systems and real-time streaming in low-power, low-bandwidth connections due to its ability to handle multiplexing and two-way communications.