- 1. API with NestJS #1. Controllers, routing and the module structure
- 2. API with NestJS #2. Setting up a PostgreSQL database with TypeORM
- 3. API with NestJS #3. Authenticating users with bcrypt, Passport, JWT, and cookies
- 4. API with NestJS #4. Error handling and data validation
- 5. API with NestJS #5. Serializing the response with interceptors
- 6. API with NestJS #6. Looking into dependency injection and modules
- 7. API with NestJS #7. Creating relationships with Postgres and TypeORM
- 8. API with NestJS #8. Writing unit tests
- 9. API with NestJS #9. Testing services and controllers with integration tests
- 10. API with NestJS #10. Uploading public files to Amazon S3
- 11. API with NestJS #11. Managing private files with Amazon S3
- 12. API with NestJS #12. Introduction to Elasticsearch
- 13. API with NestJS #13. Implementing refresh tokens using JWT
- 14. API with NestJS #14. Improving performance of our Postgres database with indexes
- 15. API with NestJS #15. Defining transactions with PostgreSQL and TypeORM
- 16. API with NestJS #16. Using the array data type with PostgreSQL and TypeORM
- 17. API with NestJS #17. Offset and keyset pagination with PostgreSQL and TypeORM
- 18. API with NestJS #18. Exploring the idea of microservices
- 19. API with NestJS #19. Using RabbitMQ to communicate with microservices
- 20. API with NestJS #20. Communicating with microservices using the gRPC framework
- 21. API with NestJS #21. An introduction to CQRS
- 22. API with NestJS #22. Storing JSON with PostgreSQL and TypeORM
- 23. API with NestJS #23. Implementing in-memory cache to increase the performance
- 24. API with NestJS #24. Cache with Redis. Running the app in a Node.js cluster
- 25. API with NestJS #25. Sending scheduled emails with cron and Nodemailer
- 26. API with NestJS #26. Real-time chat with WebSockets
- 27. API with NestJS #27. Introduction to GraphQL. Queries, mutations, and authentication
- 28. API with NestJS #28. Dealing in the N + 1 problem in GraphQL
- 29. API with NestJS #29. Real-time updates with GraphQL subscriptions
- 30. API with NestJS #30. Scalar types in GraphQL
- 31. API with NestJS #31. Two-factor authentication
- 32. API with NestJS #32. Introduction to Prisma with PostgreSQL
- 33. API with NestJS #33. Managing PostgreSQL relationships with Prisma
- 34. API with NestJS #34. Handling CPU-intensive tasks with queues
- 35. API with NestJS #35. Using server-side sessions instead of JSON Web Tokens
- 36. API with NestJS #36. Introduction to Stripe with React
- 37. API with NestJS #37. Using Stripe to save credit cards for future use
- 38. API with NestJS #38. Setting up recurring payments via subscriptions with Stripe
- 39. API with NestJS #39. Reacting to Stripe events with webhooks
- 40. API with NestJS #40. Confirming the email address
- 41. API with NestJS #41. Verifying phone numbers and sending SMS messages with Twilio
- 42. API with NestJS #42. Authenticating users with Google
- 43. API with NestJS #43. Introduction to MongoDB
- 44. API with NestJS #44. Implementing relationships with MongoDB
- 45. API with NestJS #45. Virtual properties with MongoDB and Mongoose
- 46. API with NestJS #46. Managing transactions with MongoDB and Mongoose
- 47. API with NestJS #47. Implementing pagination with MongoDB and Mongoose
- 48. API with NestJS #48. Definining indexes with MongoDB and Mongoose
- 49. API with NestJS #49. Updating with PUT and PATCH with MongoDB and Mongoose
- 50. API with NestJS #50. Introduction to logging with the built-in logger and TypeORM
- 51. API with NestJS #51. Health checks with Terminus and Datadog
- 52. API with NestJS #52. Generating documentation with Compodoc and JSDoc
- 53. API with NestJS #53. Implementing soft deletes with PostgreSQL and TypeORM
- 54. API with NestJS #54. Storing files inside a PostgreSQL database
- 55. API with NestJS #55. Uploading files to the server
- 56. API with NestJS #56. Authorization with roles and claims
- 57. API with NestJS #57. Composing classes with the mixin pattern
- 58. API with NestJS #58. Using ETag to implement cache and save bandwidth
- 59. API with NestJS #59. Introduction to a monorepo with Lerna and Yarn workspaces
- 60. API with NestJS #60. The OpenAPI specification and Swagger
- 61. API with NestJS #61. Dealing with circular dependencies
- 62. API with NestJS #62. Introduction to MikroORM with PostgreSQL
- 63. API with NestJS #63. Relationships with PostgreSQL and MikroORM
- 64. API with NestJS #64. Transactions with PostgreSQL and MikroORM
- 65. API with NestJS #65. Implementing soft deletes using MikroORM and filters
- 66. API with NestJS #66. Improving PostgreSQL performance with indexes using MikroORM
- 67. API with NestJS #67. Migrating to TypeORM 0.3
- 68. API with NestJS #68. Interacting with the application through REPL
- 69. API with NestJS #69. Database migrations with TypeORM
- 70. API with NestJS #70. Defining dynamic modules
- 71. API with NestJS #71. Introduction to feature flags
- 72. API with NestJS #72. Working with PostgreSQL using raw SQL queries
- 73. API with NestJS #73. One-to-one relationships with raw SQL queries
- 74. API with NestJS #74. Designing many-to-one relationships using raw SQL queries
- 75. API with NestJS #75. Many-to-many relationships using raw SQL queries
- 76. API with NestJS #76. Working with transactions using raw SQL queries
- 77. API with NestJS #77. Offset and keyset pagination with raw SQL queries
- 78. API with NestJS #78. Generating statistics using aggregate functions in raw SQL
- 79. API with NestJS #79. Implementing searching with pattern matching and raw SQL
- 80. API with NestJS #80. Updating entities with PUT and PATCH using raw SQL queries
- 81. API with NestJS #81. Soft deletes with raw SQL queries
- 82. API with NestJS #82. Introduction to indexes with raw SQL queries
- 83. API with NestJS #83. Text search with tsvector and raw SQL
- 84. API with NestJS #84. Implementing filtering using subqueries with raw SQL
- 85. API with NestJS #85. Defining constraints with raw SQL
- 86. API with NestJS #86. Logging with the built-in logger when using raw SQL
- 87. API with NestJS #87. Writing unit tests in a project with raw SQL
- 88. API with NestJS #88. Testing a project with raw SQL using integration tests
- 89. API with NestJS #89. Replacing Express with Fastify
- 90. API with NestJS #90. Using various types of SQL joins
- 91. API with NestJS #91. Dockerizing a NestJS API with Docker Compose
- 92. API with NestJS #92. Increasing the developer experience with Docker Compose
- 93. API with NestJS #93. Deploying a NestJS app with Amazon ECS and RDS
- 94. API with NestJS #94. Deploying multiple instances on AWS with a load balancer
- 95. API with NestJS #95. CI/CD with Amazon ECS and GitHub Actions
- 96. API with NestJS #96. Running unit tests with CI/CD and GitHub Actions
- 97. API with NestJS #97. Introduction to managing logs with Amazon CloudWatch
- 98. API with NestJS #98. Health checks with Terminus and Amazon ECS
- 99. API with NestJS #99. Scaling the number of application instances with Amazon ECS
- 100. API with NestJS #100. The HTTPS protocol with Route 53 and AWS Certificate Manager
- 101. API with NestJS #101. Managing sensitive data using the AWS Secrets Manager
- 102. API with NestJS #102. Writing unit tests with Prisma
- 103. API with NestJS #103. Integration tests with Prisma
- 104. API with NestJS #104. Writing transactions with Prisma
- 105. API with NestJS #105. Implementing soft deletes with Prisma and middleware
- 106. API with NestJS #106. Improving performance through indexes with Prisma
- 107. API with NestJS #107. Offset and keyset pagination with Prisma
- 108. API with NestJS #108. Date and time with Prisma and PostgreSQL
- 109. API with NestJS #109. Arrays with PostgreSQL and Prisma
- 110. API with NestJS #110. Managing JSON data with PostgreSQL and Prisma
- 111. API with NestJS #111. Constraints with PostgreSQL and Prisma
- 112. API with NestJS #112. Serializing the response with Prisma
- 113. API with NestJS #113. Logging with Prisma
- 114. API with NestJS #114. Modifying data using PUT and PATCH methods with Prisma
- 115. API with NestJS #115. Database migrations with Prisma
- 116. API with NestJS #116. REST API versioning
- 117. API with NestJS #117. CORS – Cross-Origin Resource Sharing
- 118. API with NestJS #118. Uploading and streaming videos
- 119. API with NestJS #119. Type-safe SQL queries with Kysely and PostgreSQL
- 120. API with NestJS #120. One-to-one relationships with the Kysely query builder
- 121. API with NestJS #121. Many-to-one relationships with PostgreSQL and Kysely
- 122. API with NestJS #122. Many-to-many relationships with Kysely and PostgreSQL
- 123. API with NestJS #123. SQL transactions with Kysely
- 124. API with NestJS #124. Handling SQL constraints with Kysely
- 125. API with NestJS #125. Offset and keyset pagination with Kysely
- 126. API with NestJS #126. Improving the database performance with indexes and Kysely
- 127. API with NestJS #127. Arrays with PostgreSQL and Kysely
- 128. API with NestJS #128. Managing JSON data with PostgreSQL and Kysely
- 129. API with NestJS #129. Implementing soft deletes with SQL and Kysely
- 130. API with NestJS #130. Avoiding storing sensitive information in API logs
- 131. API with NestJS #131. Unit tests with PostgreSQL and Kysely
- 132. API with NestJS #132. Handling date and time in PostgreSQL with Kysely
- 133. API with NestJS #133. Introducing database normalization with PostgreSQL and Prisma
- 134. API with NestJS #134. Aggregating statistics with PostgreSQL and Prisma
- 135. API with NestJS #135. Referential actions and foreign keys in PostgreSQL with Prisma
- 136. API with NestJS #136. Raw SQL queries with Prisma and PostgreSQL range types
- 137. API with NestJS #137. Recursive relationships with Prisma and PostgreSQL
- 138. API with NestJS #138. Filtering records with Prisma
- 139. API with NestJS #139. Using UUID as primary keys with Prisma and PostgreSQL
- 140. API with NestJS #140. Using multiple PostgreSQL schemas with Prisma
- 141. API with NestJS #141. Getting distinct records with Prisma and PostgreSQL
- 142. API with NestJS #142. A video chat with WebRTC and React
- 143. API with NestJS #143. Optimizing queries with views using PostgreSQL and Kysely
- 144. API with NestJS #144. Creating CLI applications with the Nest Commander
- 145. API with NestJS #145. Securing applications with Helmet
- 146. API with NestJS #146. Polymorphic associations with PostgreSQL and Prisma
- 147. API with NestJS #147. The data types to store money with PostgreSQL and Prisma
- 148. API with NestJS #148. Understanding the injection scopes
- 149. API with NestJS #149. Introduction to the Drizzle ORM with PostgreSQL
- 150. API with NestJS #150. One-to-one relationships with the Drizzle ORM
- 151. API with NestJS #151. Implementing many-to-one relationships with Drizzle ORM
- 152. API with NestJS #152. SQL constraints with the Drizzle ORM
- 153. API with NestJS #153. SQL transactions with the Drizzle ORM
- 154. API with NestJS #154. Many-to-many relationships with Drizzle ORM and PostgreSQL
- 155. API with NestJS #155. Offset and keyset pagination with the Drizzle ORM
- 156. API with NestJS #156. Arrays with PostgreSQL and the Drizzle ORM
- 157. API with NestJS #157. Handling JSON data with PostgreSQL and the Drizzle ORM
- 158. API with NestJS #158. Soft deletes with the Drizzle ORM
- 159. API with NestJS #159. Date and time with PostgreSQL and the Drizzle ORM
- 160. API with NestJS #160. Using views with the Drizzle ORM and PostgreSQL
- 161. API with NestJS #161. Generated columns with the Drizzle ORM and PostgreSQL
- 162. API with NestJS #162. Identity columns with the Drizzle ORM and PostgreSQL
- 163. API with NestJS #163. Full-text search with the Drizzle ORM and PostgreSQL
- 164. API with NestJS #164. Improving the performance with indexes using Drizzle ORM
- 165. API with NestJS #165. Time intervals with the Drizzle ORM and PostgreSQL
- 166. API with NestJS #166. Logging with the Drizzle ORM
- 167. API with NestJS #167. Unit tests with the Drizzle ORM
- 168. API with NestJS #168. Integration tests with the Drizzle ORM
Writing tests for our application helps ensure it works as intended and is reliable. So far, we have written unit tests for our NestJS application that uses the Drizzle ORM. Unit tests help us check if a particular class of a single function functions properly on its own. While unit tests are important, they are not enough. Even if each piece of our system works well alone, it does not yet mean it functions together with other parts of our system.
Introducing integration tests
To test how two or more pieces of our application work together, we write integration tests. Let’s take a look at the signUp method we wrote in the previous parts of this series.
authentication.service.ts
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import { Injectable } from '@nestjs/common'; import { UsersService } from '../users/users.service'; import * as bcrypt from 'bcrypt'; import { SignUpDto } from './dto/sign-up.dto'; @Injectable() export class AuthenticationService { constructor(private readonly usersService: UsersService) {} async signUp(signUpData: SignUpDto) { const hashedPassword = await bcrypt.hash(signUpData.password, 10); return this.usersService.create({ name: signUpData.name, email: signUpData.email, phoneNumber: signUpData.phoneNumber, password: hashedPassword, address: signUpData.address, }); } // ... } |
It hashes the provided password and calls the create method from the UsersService under the hood.
users.service.ts
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import { Injectable } from '@nestjs/common'; import { UserDto } from './user.dto'; import { DrizzleService } from '../database/drizzle.service'; import { databaseSchema } from '../database/database-schema'; import { PostgresErrorCode } from '../database/postgres-error-code.enum'; import { UserAlreadyExistsException } from './user-already-exists.exception'; import { isDatabaseError } from '../database/databse-error'; @Injectable() export class UsersService { constructor(private readonly drizzleService: DrizzleService) {} async create(user: UserDto) { try { const createdUsers = await this.drizzleService.db .insert(databaseSchema.users) .values(user) .returning(); return createdUsers.pop(); } catch (error) { if ( isDatabaseError(error) && error.code === PostgresErrorCode.UniqueViolation ) { throw new UserAlreadyExistsException(user.email); } throw error; } } // ... } |
The create method creates the user in the database and handles the error that could happen when we try to sign up a new user with an email already in our database.
There are a few things in the signUp method we could test with integration tests:
- whether it hashes the password,
- if it returns the created user if the provided data is valid
- if it throws the UserAlreadyExistsException error thrown by the create method.
Since we want to test how the AuthenticationService integrates with the UsersService, we won’t be mocking the UsersService. Instead, let’s mock the DrizzleService to ensure we’re not using the real database in our tests.
Writing integration tests does not mean we want to check how all parts of our system work together. Those tests are called end-to-end (E2E) tests and should mimic a real system as close as possible.
An important thing to notice is that we’re chaining the insert, values, and returning functions.
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const createdUsers = await this.drizzleService.db .insert(databaseSchema.users) .values(user) .returning(); |
To handle that in our tests, we can use the mockReturnThis() method.
Since hashing a password with bcrypt includes a random salt, we should mock the bcrypt library to produce the same output consistently.
authentication.service.test.ts
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import { AuthenticationService } from './authentication.service'; import { JwtModule } from '@nestjs/jwt'; import { ConfigModule } from '@nestjs/config'; import { Test } from '@nestjs/testing'; import { UsersService } from '../users/users.service'; import { SignUpDto } from './dto/sign-up.dto'; import { DrizzleService } from '../database/drizzle.service'; jest.mock('bcrypt', () => ({ hash: () => { return Promise.resolve('hashed-password'); }, })); describe('The AuthenticationService', () => { let authenticationService: AuthenticationService; let drizzleInsertReturningMock: jest.Mock; let drizzleInsertValuesMock: jest.Mock; let signUpData: SignUpDto; beforeEach(async () => { drizzleInsertValuesMock = jest.fn().mockReturnThis(); drizzleInsertReturningMock = jest.fn().mockResolvedValue([]); signUpData = { email: 'john@smith.com', name: 'John', password: 'strongPassword123', phoneNumber: '123456789', }; const module = await Test.createTestingModule({ providers: [ AuthenticationService, UsersService, { provide: DrizzleService, useValue: { db: { insert: jest.fn().mockReturnThis(), values: drizzleInsertValuesMock, returning: drizzleInsertReturningMock, }, }, }, ], imports: [ ConfigModule.forRoot(), JwtModule.register({ secretOrPrivateKey: 'Secret key', }), ], }).compile(); authenticationService = await module.get(AuthenticationService); }); describe('when the signUp function is called', () => { it('should insert the user using the Drizzle ORM', async () => { await authenticationService.signUp(signUpData); expect(drizzleInsertValuesMock).toHaveBeenCalledWith({ ...signUpData, password: 'hashed-password', }); }); }); }); |
Testing the result of the method
Now, let’s test if the signUp method returns a valid user in various cases. In the first case, the DrizzleService returns a valid user. In the second case, it throws an error because the email has already been taken.
To handle that, we must adjust our drizzleInsertReturningMock for each test using the mockResolvedValue and mockImplementation functions.
authentication.service.test.ts
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import { AuthenticationService } from './authentication.service'; import { JwtModule } from '@nestjs/jwt'; import { ConfigModule } from '@nestjs/config'; import { Test } from '@nestjs/testing'; import { UsersService } from '../users/users.service'; import { SignUpDto } from './dto/sign-up.dto'; import { DrizzleService } from '../database/drizzle.service'; import { InferSelectModel } from 'drizzle-orm'; import { databaseSchema } from '../database/database-schema'; import { DatabaseError } from '../database/databse-error'; import { PostgresErrorCode } from '../database/postgres-error-code.enum'; import { UserAlreadyExistsException } from '../users/user-already-exists.exception'; jest.mock('bcrypt', () => ({ hash: () => { return Promise.resolve('hashed-password'); }, })); describe('The AuthenticationService', () => { let authenticationService: AuthenticationService; let drizzleInsertReturningMock: jest.Mock; let drizzleInsertValuesMock: jest.Mock; let signUpData: SignUpDto; beforeEach(async () => { drizzleInsertValuesMock = jest.fn().mockReturnThis(); drizzleInsertReturningMock = jest.fn().mockResolvedValue([]); signUpData = { email: 'john@smith.com', name: 'John', password: 'strongPassword123', phoneNumber: '123456789', }; const module = await Test.createTestingModule({ providers: [ AuthenticationService, UsersService, { provide: DrizzleService, useValue: { db: { insert: jest.fn().mockReturnThis(), values: drizzleInsertValuesMock, returning: drizzleInsertReturningMock, }, }, }, ], imports: [ ConfigModule.forRoot(), JwtModule.register({ secretOrPrivateKey: 'Secret key', }), ], }).compile(); authenticationService = await module.get(AuthenticationService); }); // ... describe('when the DrizzleService returns a valid user', () => { let createdUser: InferSelectModel<typeof databaseSchema.users>; beforeEach(() => { createdUser = { ...signUpData, id: 1, addressId: null, }; drizzleInsertReturningMock.mockResolvedValue([createdUser]); }); it('should return the user as well', async () => { const result = await authenticationService.signUp(signUpData); expect(result).toBe(createdUser); }); }); describe('when the DrizzleService throws the UniqueViolation error', () => { beforeEach(() => { const databaseError: DatabaseError = { code: PostgresErrorCode.UniqueViolation, table: 'users', detail: 'Key (email)=(john@smith.com) already exists.', }; drizzleInsertReturningMock.mockImplementation(() => { throw databaseError; }); }); it('should throw the ConflictException', () => { return expect(async () => { await authenticationService.signUp(signUpData); }).rejects.toThrow(UserAlreadyExistsException); }); }); }); |
Testing controllers
An alternative approach to writing integration tests is to make HTTP requests to our API. By doing that, we can test multiple layers of our application, from the controllers to the services. To do that, we need to install the SuperTest library.
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npm install supertest @types/supertest |
First, we need to initialize our NestJS application in our tests. We will need the app variable to perform the tests with the SuperTest library.
categories.controller.test.ts
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import { INestApplication } from '@nestjs/common'; import { Test } from '@nestjs/testing'; import { CategoriesService } from './categories.service'; import { DrizzleService } from '../database/drizzle.service'; import { CategoriesController } from './categories.controller'; describe('The CategoriesController', () => { let app: INestApplication; let findFirstMock: jest.Mock; beforeEach(async () => { findFirstMock = jest.fn(); const module = await Test.createTestingModule({ providers: [ CategoriesService, { provide: DrizzleService, useValue: { db: { query: { categories: { findFirst: findFirstMock, }, }, }, }, }, ], controllers: [CategoriesController], imports: [], }).compile(); app = module.createNestApplication(); await app.init(); }); // ... }); |
Now, let’s use the SuperTest library to make GET requests to our API. When doing that, we can tackle various scenarios, such as categories with a given ID being available or not. To do that, we need to mock our DrizzleService accordingly.
categories.controller.test.ts
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import * as request from 'supertest'; import { INestApplication } from '@nestjs/common'; describe('The CategoriesController', () => { let app: INestApplication; let findFirstMock: jest.Mock; // ... describe('when the GET /categories/:id endpoint is called', () => { describe('and the category with a given id exists', () => { beforeEach(() => { findFirstMock.mockResolvedValue({ id: 1, name: 'My category', categoriesArticles: [], }); }); it('should respond with the category', () => { return request(app.getHttpServer()).get('/categories/1').expect({ id: 1, name: 'My category', articles: [], }); }); }); describe('and the category with a given id does not exist', () => { beforeEach(() => { findFirstMock.mockResolvedValue(undefined); }); it('should respond with the 404 status', () => { return request(app.getHttpServer()).get('/categories/2').expect(404); }); }); }); }); |
POST requests and authentication
We can also make POST requests and send data using the request body to add new categories. However, we must consider that our API requires the user to authenticate before doing that. To deal with that, we need to mock the JwtAuthenticationGuard.
categories.controller.test.ts
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import { ExecutionContext, INestApplication } from '@nestjs/common'; import { Test } from '@nestjs/testing'; import { CategoriesService } from './categories.service'; import { DrizzleService } from '../database/drizzle.service'; import { CategoriesController } from './categories.controller'; import { JwtAuthenticationGuard } from '../authentication/jwt-authentication.guard'; describe('The CategoriesController', () => { let app: INestApplication; let findFirstMock: jest.Mock; let drizzleInsertReturningMock: jest.Mock; beforeEach(async () => { drizzleInsertReturningMock = jest.fn().mockResolvedValue([]); findFirstMock = jest.fn(); const module = await Test.createTestingModule({ providers: [ CategoriesService, { provide: DrizzleService, useValue: { db: { query: { categories: { findFirst: findFirstMock, }, }, insert: jest.fn().mockReturnThis(), values: jest.fn().mockReturnThis(), returning: drizzleInsertReturningMock, }, }, }, ], controllers: [CategoriesController], imports: [], }) .overrideGuard(JwtAuthenticationGuard) .useValue({ canActivate: (context: ExecutionContext) => { const req = context.switchToHttp().getRequest(); req.user = { id: 1, name: 'John Smith', }; return true; }, }) .compile(); app = module.createNestApplication(); await app.init(); }); // ... }); |
Thanks to the above, we can test if adding new categories works as expected.
categories.controller.test.ts
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import * as request from 'supertest'; import { ExecutionContext, INestApplication } from '@nestjs/common'; import { Test } from '@nestjs/testing'; import { CategoriesService } from './categories.service'; import { DrizzleService } from '../database/drizzle.service'; import { CategoriesController } from './categories.controller'; import { JwtAuthenticationGuard } from '../authentication/jwt-authentication.guard'; import { CategoryDto } from './dto/category.dto'; describe('The CategoriesController', () => { let app: INestApplication; let findFirstMock: jest.Mock; let drizzleInsertReturningMock: jest.Mock; beforeEach(async () => { drizzleInsertReturningMock = jest.fn().mockResolvedValue([]); findFirstMock = jest.fn(); const module = await Test.createTestingModule({ providers: [ CategoriesService, { provide: DrizzleService, useValue: { db: { query: { categories: { findFirst: findFirstMock, }, }, insert: jest.fn().mockReturnThis(), values: jest.fn().mockReturnThis(), returning: drizzleInsertReturningMock, }, }, }, ], controllers: [CategoriesController], imports: [], }) .overrideGuard(JwtAuthenticationGuard) .useValue({ canActivate: (context: ExecutionContext) => { const req = context.switchToHttp().getRequest(); req.user = { id: 1, name: 'John Smith', }; return true; }, }) .compile(); app = module.createNestApplication(); await app.init(); }); // ... describe('when the POST /categories endpoint is called', () => { describe('and the correct data is provided', () => { let categoryData: CategoryDto; beforeEach(() => { categoryData = { name: 'New category', }; drizzleInsertReturningMock.mockResolvedValue([ { id: 2, ...categoryData, }, ]); }); it('should respond with the new category', () => { return request(app.getHttpServer()) .post('/categories') .send(categoryData) .expect({ id: 2, ...categoryData, }); }); }); }); }); |
Summary
In this article, we explored the concept of integration tests in NestJS applications using the Drizzle ORM. We discussed why they’re important and how they benefit us. We also implemented two different approaches to integration tests, one of which involved using the SuperTest library to simulate HTTP requests. Thanks to the above, we can test our API more effectively and have a more reliable, stable application.