What are gRPC, GraphQL and REST?

REST, gRPC, and GraphQL are three different communication protocols used in web development for client-server interactions. Each has its own strengths and use cases, which we’ll discuss in brief. For more detail, check the related articles.

Representational State Transfer (REST)

REST is an architectural style based on distributed technologically-agnostic elements that communicate with each other. It emphasizes scalability of interaction between components, uniform interfaces, independent deployment of components, and a layered architecture to facilitate component caching to reduce latency, enforce security, and encapsulate legacy systems.

RESTful communication is based on client-server architecture and uses HTTP 1.1 (HTTP) protocol to exchange data in any format, although JavaScript Object Notation (JSON) or Extensible Markup Language (XML) are most common.

REST API is well-established and easy to understand for developers, since it uses Uniform Resource Identifiers (URIs) to call service endpoints and HTTP actions for standard CRUD (Create, Read, Update, Delete) operations. It also enables data filtering, use of HTTP code with arbitrary descriptions in responses, and access control. It is also extendable.

• Pros:
  • Easy to understand and implement.
  • Widely supported by existing tools and libraries.
  • Stateless architecture and uniform interface constraints promote scalability.
• Cons:
  • Prone to over-fetching, as the server decides the response data structure.
  • Lack of real-time capabilities, leading to the need for additional protocols for real-time features (such as WebSocket).

Google Remote Procedure Calls (gRPC)

GRPC is an open-source RPC (Remote Procedure Call) framework developed by Google for highly efficient real-time applications, microservices architectures, and scenarios where high performance and low latency are crucial.

It uses HTTP/2, which provides bidirectional multiplexed communication, load balancing, tracing, health checking, and authentication. Data is transmitted in binary form using Protocol Buffers (protobuf) as the default serialization format, which is efficient and language agnostic.

• Pros:
  • Efficient and high-performance due to HTTP/2, binary data format, more formalized error messages without query and path parameters.
  • Strongly-typed schema with Protocol Buffers.
  • Bidirectional streaming and server/client streaming capabilities.
  • Generates initial code for message and service definitions.
• Cons:
  • Can be more complex to set up compared to REST.
  • Although gRPC has support for many programming languages, it does not support every language.

GraphQL

GraphQL is a query language and runtime for APIs developed by Meta. It is well-suited for applications with varying data requirements, and when the client needs control over the data it receives.

It can use HTTP or other transport protocols like WebSocket. GraphQL transmits data with JSON as the default serialization format, but it allows clients to request only the data they need.

• Pros:
  • Clients can specify the exact data they need, reducing over-fetching and under-fetching issues.
  • Strongly-typed schema, introspection, and documentation support.
  • Real-time features can be implemented using WebSocket.
• Cons:
  • May lead to more complex queries on the client side.
  • Adds some server-side complexities, especially for batch data fetching.

Summary

Which protocol is best depends on the application's specific requirements. If performance and efficiency are critical, gRPC might be a good fit. If you need more flexibility in data retrieval, GraphQL is a strong contender. On the other hand, if you prefer a simpler, well-established approach with standardized operations, REST remains a reliable choice.