CRUD with Prisma

src/products/products.service.ts

import { Injectable, NotFoundException } from '@nestjs/common';
import { Prisma } from '@prisma/client';
import { PrismaService } from '../prisma/prisma.service';
import { CreateProductDto } from './dto/create-product.dto';
import { UpdateProductDto } from './dto/update-product.dto';

@Injectable()
export class ProductsService {
  constructor(private readonly prisma: PrismaService) {}

  findAll(category?: string) {
    return this.prisma.product.findMany({
      where: category ? { category: { slug: category } } : undefined,
      include: { category: { select: { slug: true, name: true } } },
      orderBy: { createdAt: 'desc' },
      take: 20,
    });
  }

  async findOne(id: number) {
    const product = await this.prisma.product.findUnique({ where: { id }, include: { category: true } });
    if (!product) throw new NotFoundException(`Product ${id} not found`);
    return product;
  }

  create(dto: CreateProductDto & { categoryId: number }) {
    return this.prisma.product.create({ data: dto });
  }

  async update(id: number, dto: UpdateProductDto) {
    try {
      return await this.prisma.product.update({ where: { id }, data: dto });
    } catch (e) {
      if (e instanceof Prisma.PrismaClientKnownRequestError && e.code === 'P2025') {
        throw new NotFoundException(`Product ${id} not found`);
      }
      throw e;
    }
  }

  remove(id: number) {
    return this.prisma.product.delete({ where: { id } });
  }
}