Prisma ORM : Bonnes pratiques en production

Pourquoi Prisma ?

Prisma est devenu l'ORM de référence pour les projets TypeScript. Sa type-safety, ses migrations automatiques et sa documentation le rendent incontournable.

Schema Design

Utilisez des Enums

enum Role {
  USER
  ADMIN
  MODERATOR
}

model User {
  id    String @id @default(cuid())
  email String @unique
  role  Role   @default(USER)
}

Relations Correctement Typées

model Post {
  id        String   @id @default(cuid())
  title     String
  author    User     @relation(fields: [authorId], references: [id])
  authorId  String
  tags      Tag[]
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt

  @@index([authorId])
}

Performance

Utilisez select au lieu de findMany

// ❌ Bad — charge tout
const users = await prisma.user.findMany();

// ✅ Good — ne charge que ce dont on a besoin
const users = await prisma.user.findMany({
  select: {
    id: true,
    name: true,
    email: true,
  },
});

Pagination avec Cursor

const posts = await prisma.post.findMany({
  take: 20,
  skip: 1, // Skip the cursor
  cursor: { id: lastPostId },
  orderBy: { createdAt: "desc" },
});

Transactions

const [user, post] = await prisma.$transaction([
  prisma.user.create({ data: { email: "test@example.com" } }),
  prisma.post.create({ data: { title: "Mon premier article" } }),
]);

Batch Operations

// Insertion en masse
await prisma.post.createMany({
  data: posts.map((p) => ({ title: p.title, content: p.content })),
  skipDuplicates: true,
});

Migrations

Workflow Recommandé

# 1. Modifier le schema
# 2. Générer la migration
npx prisma migrate dev --name add_comments_table

# 3. Vérifier le diff
# 4. Appliquer en staging
npx prisma migrate deploy

# 5. Appliquer en production
npx prisma migrate deploy

Seeding

// prisma/seed.ts
import { PrismaClient } from "@prisma/client";
import bcrypt from "bcryptjs";

const prisma = new PrismaClient();

async function main() {
  await prisma.user.upsert({
    where: { email: "admin@wabtechs.com" },
    update: {},
    create: {
      email: "admin@wabtechs.com",
      name: "Admin",
      password: await bcrypt.hash("Admin@12345", 12),
      role: "ADMIN",
    },
  });
}

main()
  .catch((e) => {
    console.error(e);
    process.exit(1);
  })
  .finally(async () => {
    await prisma.$disconnect();
  });

Pièges Courants

N+1 Queries