gRPC: High-Performance Microservices with Protocol Buffers

Presentation guide on gRPC, Protocol Buffers, HTTP/2 multiplexing, and the Backend for Frontend (BFF) architectural pattern using Node.js and Python.

Team Members

• Fiber Piedrahita
• Daniel Fajardo
• Paula Ferreira

---

Slides and Resources

gRPC-Pokedex

Project Links and Presentation

• Presentation (PDF): Download gRPC-Pokedex.pdf
• Official Protocol Buffers Documentation: Protobuf Dev

---

1. gRPC and Protocol Buffers Foundations

gRPC (gRPC Remote Procedure Calls) is an open-source, high-performance RPC framework initially designed by Google. Unlike conventional REST architectures passing textual JSON payloads over HTTP/1.1, gRPC is anchored on two core technical pillars:

1. Protocol Buffers (Protobuf): A language-neutral, platform-neutral, extensible mechanism for serializing structured binary data.
2. HTTP/2 Transport: Supports full request multiplexing over a single persistent TCP connection, header compression (HPACK), and bi-directional streaming.

Clic para ampliar

---

2. Comparison: gRPC vs. REST

Criteria	gRPC	Traditional REST
Transport Protocol	HTTP/2 (Multiplexed)	Typically HTTP/1.1 or HTTP/2
Payload Format	Binary (Protocol Buffers)	Textual (JSON or XML)
Contract Definition	Mandatory and strict (.proto)	Optional (OpenAPI / Swagger)
Performance	High throughput, minimal network serialization overhead	Moderate overhead from JSON text serialization
Streaming Modes	Unary, Server Streaming, Client Streaming, Bidirectional	Predominantly unary request/response
Primary Use Case	Inter-service microservice backplanes	Public-facing web APIs consumed by browsers

---

3. Practical Demo: Pokédex with BFF Architecture

1

Define Contract in Protocol Buffers

proto/pokemon.proto

syntax = "proto3";

package pokemon;

service PokemonService {
  rpc GetPokemon (PokemonRequest) returns (PokemonResponse);
}

message PokemonRequest {
  string name_or_id = 1;
}

message PokemonResponse {
  int32 id = 1;
  string name = 2;
  int32 height = 3;
  int32 weight = 4;
  repeated string types = 5;
  string sprite_url = 6;
  string description = 7;
}

2

Implement gRPC Server in Node.js

The Node.js server compiles the .proto schema, queries the upstream PokeAPI, and responds to gRPC clients via structured binary streams:

cd backend_node
npm install
node server.js

3

Implement Python gRPC Client (Flask BFF)

The Python Backend for Frontend (BFF) consumes the gRPC service and serves HTML/JSON to the client browser:

Practical Demo: Pokédex with BFF

cd frontend_python
python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate
pip install -r requirements.txt
python app.py