gRPC or REST

Agenda ❖ API, Types and Specifications. ❖ What is REST? ❖ Disadvantages of REST. ❖ What is gRPC? ❖ Advantages of gRPC.

What is an API?

Whats is an API? ❖ API stands for Application Programming Interface. ❖ Acts as a communication bridge between two systems. ❖ Enables software components to interact seamlessly. ➢ Example: Mobile app requesting weather data from a server.

Types of APIs ❖ Web APIs: Interact over the internet (e.g., REST, gRPC). ❖ Library APIs: Access pre-built code libraries. ❖ OS APIs: Enable interaction with OS features. ❖ Hardware APIs: Interface with physical devices. ➢ Example: Mobile app requesting weather data from a server.

API Specification ❖ Definition: A document that describes how to interact with an API. ❖ Includes: ■ Endpoints. ■ Methods (GET, POST, etc.). ■ Data formats (JSON, XML, Protobuf). ■ Authentication and error handling. ❖ Ensures consistency and predictable integration. ➢ Popular API specification formats: RESTful APIs, GraphQL, SOAP, gRPC

REST || gRPC

REST ❖ Representational State Transfer ❖ Not a protocol but a Design Pattern ❖ Uses HTTP protocol ❖ Objects that are send or saved are called resources ❖ Operations are described by HTTP verbs ❖ Transfer data as XML or JSON

❖ A RESTful API can be - XML + HTTP JSON + HTTP

What does a RESTful API call look like?

Disadvantage of REST ❖ The data being transferred is heavily bloated.

Bloated Data

Disadvantage of REST ❖ The data being transferred is heavily bloated. ❖ There is no formal contract to communicate. ❖ HTTP verb don’t always describe your API. ❖ Streaming is difficult.

What if not REST?

gRPC ❖ gRPC Remote Procedure Call ❖ Modern open-source RPC framework by Google ❖ High Performance RPC framework ❖ Uses HTTP/2 for efficient data transmission. ❖ Uses Protocol Buffers for message interchange and for the fast binary serialization.

Writing a gRPC Service (3 Steps)

Let's make a calculator service:

❖ Interface Definition Language (IDL) ❖ Message Interchange format ❖ Platform neutral mechanism for serializing structured data. Protocol Buffers

Let's make a calculator Services:

No content

No content

No content

No content

❖ Generated code in 10 language ❖ Strict contract between client and server ❖ Performant and efficient on the wire Small binary message Faster serialization and deserialization ❖ In addition to traditional unary APIs, we get: Client Streaming APIs Server Streaming APIs Bi-Directional Streaming APIs Why gRPC? What do I get?

❖ High-Performance Systems: Ideal for APIs and microservices requiring speed and efficiency, thanks to HTTP/2 and Protocol Buffers. ❖ Distributed Systems: Advanced features like authentication, bidirectional streaming, and flow control make it powerful for distributed architectures. ❖ Polyglot Environments: Supports multiple languages, enabling APIs for diverse client ecosystems. ❖ Mobile Apps: Efficient network usage and bidirectional streaming make it suitable for mobile API consumption. When to use gRPC?

★ https://grpc.io/ ★ https://github.com/grpc ★ https://grpc.io/docs/ More about gRPC

Thank you!!