create: prisma module to connect with db

src/prisma/prisma.module.ts

@@ -0,0 +1,9 @@
+import { Global, Module } from '@nestjs/common';
+import { PrismaService } from './prisma.service';
+
+@Global()
+@Module({
+  providers: [PrismaService],
+  exports: [PrismaService],
+})
+export class PrismaModule {}

src/prisma/prisma.service.ts

@@ -0,0 +1,23 @@
+import { Injectable } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { PrismaClient } from '@prisma/client';
+
+@Injectable()
+export class PrismaService extends PrismaClient {
+  constructor(config: ConfigService) {
+    super({
+      datasources: {
+        db: {
+          url: config.get('DATABASE_URL'),
+        },
+      },
+    });
+  }
+
+  cleanDb() {
+    return this.$transaction([
+      this.bookmark.deleteMany(),
+      this.user.deleteMany(),
+    ]);
+  }
+}