Why not use WebSocket instead of gRPC streaming?

WebSocket and gRPC streaming solve similar tasks — two-way communication between client and server, but have different features and areas of application.

Why you shouldn't always use WebSocket instead of gRPC streaming:

• Protocol and standardization: gRPC is based on HTTP/2, which provides built-in support for streams, multiplexing, compression, and efficient connection management. WebSocket is a separate protocol over HTTP/1.1, which requires additional logic for message and state management.

• Typing and contract: gRPC uses protobuf for strict typing and API contract definition, simplifying development and maintenance. WebSocket transmits raw bytes or text, and serialization/deserialization responsibility lies with the developer.

• Integration with ecosystem: gRPC integrates well with modern tools, supports automatic code generation, load balancing, authentication, and other features. WebSocket requires more manual work to implement similar functions.

• Performance: gRPC streaming is optimized for high-performance scenarios with low latency and less overhead traffic thanks to HTTP/2.

• Compatibility: WebSocket may be preferable if you need to support browsers directly without additional libraries, as gRPC in browsers requires gRPC-Web or a proxy.

Summary: If you need strictly typed, scalable, and efficient two-way communication with support for complex contracts and integrations — gRPC streaming is better. If you need a simple two-way connection with a browser and flexible message passing — WebSocket may be more convenient.