Introduction à la Clean Architecture
Présenté par Maël Sicard-Cras
Introduction
Qui suis-je?
Qui êtes vous?
Vous & la Clean Architecture?
Les obstacles typiques rencontrés par les développeurs
Changement de Technologie
Internal breaking changes
Code peu clair
Code non testable
Alors parlons de ...
CLEAN ARCHITECTURE
Concept charactérisé par:
- Bonnes pratiques regroupées
- Indépendant du framework
- Indépendant des technologies
- Testabilité
- Clean code
La théorie
Notre code
const fastify = require('fastify')({ logger: true })
fastify.get('/api/v1/malwares', async (request, reply) => {
return await orm.getRepository(Malware).find();
})
fastify.get('/api/v1/malwares/:id', async (request, reply) => {
return await orm.getRepository(Malware).findOne(request.params.id);
})
const start = async () => {
await fastify.listen({ port: 3000 })
}
start()
Le Domain Driven Design
Le Domain Driven Design
const fastify = require('fastify')({ logger: true })
interface MalwareEntity {
actor: string;
malwareName: string;
}
async getAllMalwares(): Promise<MalwareEntity[]> {
return await orm.getRepository(Malware).find();
}
async getMalwareById(id: number): Promise<MalwareEntity> {
return await orm.getRepository(Malware).findOne(id);
}
fastify.get('/api/v1/malwares', async (request, reply) => {
return await getAllMalwares()
})
fastify.get('/api/v1/malwares/:id', async (request, reply) => {
return await getMalwareById(request.params.id)
})
const start = async () => {
await fastify.listen({ port: 3000 })
}
start()
L'architecture héxagonale
L'architecture héxagonale
const fastify = require('fastify')({ logger: true })
// Domain
interface MalwareEntity {
actor: string;
malwareName: string;
}
// SPI (Application <---> Database)
async getAllMalwares(): Promise<MalwareEntity[]> {
return await orm.getRepository(Malware).find();
}
async getMalwareById(id: number): Promise<MalwareEntity> {
return await orm.getRepository(Malware).findOne(id);
}
// API (Clients <---> Application)
fastify.get('/api/v1/malwares', async (request, reply) => {
return await getAllMalwares()
})
fastify.get('/api/v1/malwares/:id', async (request, reply) => {
return await getMalwareById(request.params.id)
})
const start = async () => {
await fastify.listen({ port: 3000 })
}
start()
Les strates de la Clean Architecture
Les strates de la Clean Architecture
// 1 - EXTERNAL INTERFACES: src/infrastructure/app.ts
const fastify = require('fastify')({ logger: true })
const start = async () => {
await fastify.listen({ port: 3000 })
}
start()
// 2 - ADAPTER (SPI): src/adapter/spi/db/repository.ts
async getAllMalwares(): Promise<MalwareEntity[]> {
return await orm.getRepository(Malware).findOne(id);
}
async getMalwareById(id: number): Promise<MalwareEntity> {
return await orm.getRepository(Malware).find();
}
// 2 - ADAPTER (API): src/adapter/api/controller.ts
fastify.get('/api/v1/malwares', async (request, reply) => {
return await new GetAllMalwaresUseCase().execute()
})
fastify.get('/api/v1/malwares/:id', async (request, reply) => {
return await new GetOneMalwareByIdUseCase(request.params.id).execute()
})
// 3 - USE CASES: src/application/usecases/getAllMalwaresUseCase.ts
class GetAllMalwaresUseCase{
async execute(): Promise<MalwareEntity[]> {
return await repository.getAllMalwares();
}
}
// 3 - USE CASES: src/application/usecases/GetOneMalwareByIdUseCase.ts
class GetOneMalwareByIdUseCase{
async execute(): Promise<MalwareEntity> {
return await repository.getMalwareById(id);
}
}
// 4 - ENTITIES: src/domain/entities.ts
interface MalwareEntity {
actor: string;
malwareName: string;
}
Dependency Rule
Dependency Rule incorrecte
//current path: src/application/usecases/GetOneMalwareByIdUseCase.ts
import {MalwaresMySqlRepository} from "src/adapter/spi/db/malwares_repository";
import {MalwareEntity} from "src/domain/entities/malware_entity";
export class GetAllMalwaresUseCase {
private repository: MalwaresMySqlRepository;
constructor() {
this.repository = new MalwaresMySqlRepository();
}
async execute(): Promise<MalwareEntity[]> {
return await this.repository.getAllMalwares();
}
}
Dependency Rule correcte
//current path: src/application/usecases/GetOneMalwareByIdUseCase.ts
import {MalwaresRepositoryInterface} from "src/application/repositories/malwares_repository_interface";
import {MalwareEntity} from "src/domain/entities/malware_entity";
export class GetAllMalwaresUseCase {
private repository: MalwaresRepositoryInterface;
constructor(repository: MalwaresRepositoryInterface) {
this.repository = repository;
}
async execute(): Promise<MalwareEntity[]> {
return await this.repository.getAllMalwares();
}
}
Demo
Cats & Dogs Facts API
- API de faits divers sur les animaux
- 2 UseCases par animal (tous ou certains faits)
- Structure JSON différentes entre animaux
- Données lues depuis la DB et API externe
Hexagonal Architecture
Data flow
VsCode
Cas pratique
Décision managériale!!!
- Pas d'investissement dans le cloud...
- On préfère maintenir une DB en local
- On migre le service HTTP & les données
- Nos clients ne doivent pas s'en rendre compte
Video Typescript
Video Python
Conclusion
Résumé
- Domain driven design
- Hexagonal architecture
- Dependency rule
- Dependency injection
Pros (& cons)
- Isolation des domaines & logiques métier
- Simple et peu couteux de changer de technologie
- Reste flexible & scalable sur des gros projets
- Aisance de test
Notre code ?
const fastify = require('fastify')({ logger: true })
fastify.get('/api/v1/malwares', async (request, reply) => {
return await orm.getRepository(Malware).find();
})
fastify.get('/api/v1/malwares/:id', async (request, reply) => {
return await orm.getRepository(Malware).findOne(request.params.id);
})
const start = async () => {
await fastify.listen({ port: 3000 })
}
start()
“It is not enough for code to work...”Robert C. Martin (Uncle Bob)’s Clean Code: A Handbook of Agile Software Craftsmanship
Merci
Github
https://github.com/MSC29
- clean-architecture-typescript
- clean-architecture-python
- clean-architecture-rust
- clean-architecture-go
Article en ligne
https://dev.to/msc29