- 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
- 169. API with NestJS #169. Unique IDs with UUIDs using Drizzle ORM and PostgreSQL
- 170. API with NestJS #170. Polymorphic associations with PostgreSQL and Drizzle ORM
- 171. API with NestJS #171. Recursive relationships with Drizzle ORM and PostgreSQL
- 172. API with NestJS #172. Database normalization with Drizzle ORM and PostgreSQL
- 173. API with NestJS #173. Storing money with Drizzle ORM and PostgreSQL
- 174. API with NestJS #174. Multiple PostgreSQL schemas with Drizzle ORM
- 175. API with NestJS #175. PUT and PATCH requests with PostgreSQL and Drizzle ORM
- 176. API with NestJS #176. Database migrations with the Drizzle ORM
- 177. API with NestJS #177. Response serialization with the Drizzle ORM
So far, in this series, we’ve described two ways of storing files on a server. In the 10th article, we’ve uploaded files to Amazon S3. While it is very scalable, we might not want to use cloud services such as AWS for various reasons. Therefore, in the 54th part of the series, we’ve learned how to store files straight in our PostgreSQL database. While it has some advantages, it might be perceived as less than ideal in terms of performance.
In this article, we look into using NestJS to store uploaded files on the server. Again, we persist some information into the database, but it is just the metadata this time.
Storing the files on the server
Fortunately, NestJS makes it very easy to store the files on the server. We need to pass additional arguments to the FileInterceptor.
users.service.ts
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import { UsersService } from './users.service'; import { Controller, Post, Req, UploadedFile, UseGuards, UseInterceptors } from '@nestjs/common'; import JwtAuthenticationGuard from '../authentication/jwt-authentication.guard'; import RequestWithUser from '../authentication/requestWithUser.interface'; import { Express } from 'express'; import { FileInterceptor } from '@nestjs/platform-express'; import { diskStorage } from 'multer'; @Controller('users') export class UsersController { constructor( private readonly usersService: UsersService, ) {} @Post('avatar') @UseGuards(JwtAuthenticationGuard) @UseInterceptors(FileInterceptor('file', { storage: diskStorage({ destination: './uploadedFiles/avatars' }) })) async addAvatar(@Req() request: RequestWithUser, @UploadedFile() file: Express.Multer.File) { return this.usersService.addAvatar(request.user.id, { path: file.path, filename: file.originalname, mimetype: file.mimetype }); } } |
When we do the above, NestJS stores uploaded files in the ./uploadedFiles/avatars directory.
There are a few issues with the above approach, though. First, we might need more than one endpoint to accept files. In such a case, we would need to repeat some parts of the configuration for each one of them. Also, we should put the ./uploadedFiles part of the destination in an environment variable to change it based on the environment the app runs in.
Extending the FileInterceptor
A way to achieve the above is to extend the FileInterceptor. After looking under the hood of NestJS, we can see that it uses the mixin pattern. Because FileInterceptor is not a class, we can’t use the extend keyword.
We want to extend the FileInterceptor functionalities while:
- having Dependency Injection to inject the ConfigService,
- being able to pass additional properties from the controller.
To do that, we can create our mixin:
localFiles.interceptor.ts
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import { FileInterceptor } from '@nestjs/platform-express'; import { Injectable, mixin, NestInterceptor, Type } from '@nestjs/common'; import { ConfigService } from '@nestjs/config'; import { MulterOptions } from '@nestjs/platform-express/multer/interfaces/multer-options.interface'; import { diskStorage } from 'multer'; interface LocalFilesInterceptorOptions { fieldName: string; path?: string; } function LocalFilesInterceptor (options: LocalFilesInterceptorOptions): Type<NestInterceptor> { @Injectable() class Interceptor implements NestInterceptor { fileInterceptor: NestInterceptor; constructor(configService: ConfigService) { const filesDestination = configService.get('UPLOADED_FILES_DESTINATION'); const destination = `${filesDestination}${options.path}` const multerOptions: MulterOptions = { storage: diskStorage({ destination }) } this.fileInterceptor = new (FileInterceptor(options.fieldName, multerOptions)); } intercept(...args: Parameters<NestInterceptor['intercept']>) { return this.fileInterceptor.intercept(...args); } } return mixin(Interceptor); } export default LocalFilesInterceptor; |
Above, we use the UPLOADED_FILES_DESTINATION variable and concatenate it with the provided path. To do that, let’s define the necessary environment variable.
app.module.ts
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import { Module } from '@nestjs/common'; import { ConfigModule } from '@nestjs/config'; import * as Joi from '@hapi/joi'; @Module({ imports: [ ConfigModule.forRoot({ validationSchema: Joi.object({ UPLOADED_FILES_DESTINATION: Joi.string().required(), // ... }) }), // ... ], // ... }) export class AppModule { // ... } |
.env
1 2 |
UPLOADED_FILES_DESTINATION=./uploadedFiles # ... |
When all of the above is ready, we can use the LocalFilesInterceptor in our controller:
users.controller.ts
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import { UsersService } from './users.service'; import { Controller, Post, Req, UploadedFile, UseGuards, UseInterceptors } from '@nestjs/common'; import JwtAuthenticationGuard from '../authentication/jwt-authentication.guard'; import RequestWithUser from '../authentication/requestWithUser.interface'; import { Express } from 'express'; import LocalFilesInterceptor from '../localFiles/localFiles.interceptor'; @Controller('users') export class UsersController { constructor( private readonly usersService: UsersService, ) {} @Post('avatar') @UseGuards(JwtAuthenticationGuard) @UseInterceptors(LocalFilesInterceptor({ fieldName: 'file', path: '/avatars' })) async addAvatar(@Req() request: RequestWithUser, @UploadedFile() file: Express.Multer.File) { return this.usersService.addAvatar(request.user.id, { path: file.path, filename: file.originalname, mimetype: file.mimetype }); } } |
Saving the metadata in the database
Besides storing the file on the server, we also need to save the file’s metadata in the database. Since NestJS generates a random filename for uploaded files, we also want to store the original filename. To do all of the above, we need to create an entity for the metadata.
localFile.entity.ts
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import { Column, Entity, PrimaryGeneratedColumn } from 'typeorm'; @Entity() class LocalFile { @PrimaryGeneratedColumn() public id: number; @Column() filename: string; @Column() path: string; @Column() mimetype: string; } export default LocalFile; |
localFile.dto.ts
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interface LocalFileDto { filename: string; path: string; mimetype: string; } |
We also need to create a relationship between users and files.
user.entity.ts
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import { Column, Entity, JoinColumn, OneToOne, PrimaryGeneratedColumn } from 'typeorm'; import LocalFile from '../localFiles/localFile.entity'; @Entity() class User { @PrimaryGeneratedColumn() public id: number; @JoinColumn({ name: 'avatarId' }) @OneToOne( () => LocalFile, { nullable: true } ) public avatar?: LocalFile; @Column({ nullable: true }) public avatarId?: number; // ... } export default User; |
We add the avatarId column above so that the entity of the user can hold the id of the avatar without joining all of the data of the avatar.
While we’re at it, we also need to create the basics of the LocalFilesService:
localFiles.service.ts
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import { Injectable } from '@nestjs/common'; import { InjectRepository } from '@nestjs/typeorm'; import { Repository } from 'typeorm'; import LocalFile from './localFile.entity'; @Injectable() class LocalFilesService { constructor( @InjectRepository(LocalFile) private localFilesRepository: Repository<LocalFile>, ) {} async saveLocalFileData(fileData: LocalFileDto) { const newFile = await this.localFilesRepository.create(fileData) await this.localFilesRepository.save(newFile); return newFile; } } export default LocalFilesService; |
The last step is to use the saveLocalFileData method in the UsersService:
users.service.ts
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import { Injectable } from '@nestjs/common'; import { InjectRepository } from '@nestjs/typeorm'; import { Repository, Connection, In } from 'typeorm'; import User from './user.entity'; import LocalFilesService from '../localFiles/localFiles.service'; @Injectable() export class UsersService { constructor( @InjectRepository(User) private usersRepository: Repository<User>, private localFilesService: LocalFilesService ) {} async addAvatar(userId: number, fileData: LocalFileDto) { const avatar = await this.localFilesService.saveLocalFileData(fileData); await this.usersRepository.update(userId, { avatarId: avatar.id }) } // ... } |
Retrieving the files
Now, the user can retrieve the id of their avatar.
To download the file with a given id, we can create a controller that streams the content.
The first step in achieving the above is extending the LocalFilesService:
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import { Injectable, NotFoundException } from '@nestjs/common'; import { InjectRepository } from '@nestjs/typeorm'; import { Repository } from 'typeorm'; import LocalFile from './localFile.entity'; @Injectable() class LocalFilesService { constructor( @InjectRepository(LocalFile) private localFilesRepository: Repository<LocalFile>, ) {} async getFileById(fileId: number) { const file = await this.localFilesRepository.findOne(fileId); if (!file) { throw new NotFoundException(); } return file; } // ... } export default LocalFilesService; |
We also need to create a controller that uses the above method:
localFiles.controller.ts
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import { Controller, Get, Param, UseInterceptors, ClassSerializerInterceptor, StreamableFile, Res, ParseIntPipe, } from '@nestjs/common'; import LocalFilesService from './localFiles.service'; import { Response } from 'express'; import { createReadStream } from 'fs'; import { join } from 'path'; @Controller('local-files') @UseInterceptors(ClassSerializerInterceptor) export default class LocalFilesController { constructor( private readonly localFilesService: LocalFilesService ) {} @Get(':id') async getDatabaseFileById(@Param('id', ParseIntPipe) id: number, @Res({ passthrough: true }) response: Response) { const file = await this.localFilesService.getFileById(id); const stream = createReadStream(join(process.cwd(), file.path)); response.set({ 'Content-Disposition': `inline; filename="${file.filename}"`, 'Content-Type': file.mimetype }) return new StreamableFile(stream); } } |
We learn about the StreamableFile class and the Content-Disposition header in the previous part of this series.
Doing the above allows the user to retrieve the file with a given id.
Filtering incoming files
We shouldn’t always trust the files our users upload. Fortunately, we can easily filter them with the fileFilter and limits properties supported by multer.
localFiles.interceptor.ts
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 |
import { FileInterceptor } from '@nestjs/platform-express'; import { Injectable, mixin, NestInterceptor, Type } from '@nestjs/common'; import { ConfigService } from '@nestjs/config'; import { MulterOptions } from '@nestjs/platform-express/multer/interfaces/multer-options.interface'; import { diskStorage } from 'multer'; interface LocalFilesInterceptorOptions { fieldName: string; path?: string; fileFilter?: MulterOptions['fileFilter']; limits?: MulterOptions['limits']; } function LocalFilesInterceptor (options: LocalFilesInterceptorOptions): Type<NestInterceptor> { @Injectable() class Interceptor implements NestInterceptor { fileInterceptor: NestInterceptor; constructor(configService: ConfigService) { const filesDestination = configService.get('UPLOADED_FILES_DESTINATION'); const destination = `${filesDestination}${options.path}` const multerOptions: MulterOptions = { storage: diskStorage({ destination }), fileFilter: options.fileFilter, limits: options.limits } this.fileInterceptor = new (FileInterceptor(options.fieldName, multerOptions)); } intercept(...args: Parameters<NestInterceptor['intercept']>) { return this.fileInterceptor.intercept(...args); } } return mixin(Interceptor); } export default LocalFilesInterceptor; |
Let’s allow only files that include “image” in the mimetype and are smaller than 1MB.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 |
import { UsersService } from './users.service'; import { BadRequestException, Controller, Post, Req, UploadedFile, UseGuards, UseInterceptors } from '@nestjs/common'; import JwtAuthenticationGuard from '../authentication/jwt-authentication.guard'; import RequestWithUser from '../authentication/requestWithUser.interface'; import { Express } from 'express'; import LocalFilesInterceptor from '../localFiles/localFiles.interceptor'; @Controller('users') export class UsersController { constructor( private readonly usersService: UsersService, ) {} @Post('avatar') @UseGuards(JwtAuthenticationGuard) @UseInterceptors(LocalFilesInterceptor({ fieldName: 'file', path: '/avatars', fileFilter: (request, file, callback) => { if (!file.mimetype.includes('image')) { return callback(new BadRequestException('Provide a valid image'), false); } callback(null, true); }, limits: { fileSize: Math.pow(1024, 2) // 1MB } })) async addAvatar(@Req() request: RequestWithUser, @UploadedFile() file: Express.Multer.File) { return this.usersService.addAvatar(request.user.id, { path: file.path, filename: file.originalname, mimetype: file.mimetype }); } } |
If the file doesn’t meet the size requirements, NestJS throws 413 Payload Too Large. It could be a good idea to go beyond just checking the mimetype and using the file-type library.
Summary
In this article, we’ve covered the basics of managing files on our server through NestJS. We’ve learned how to store them on the server and return them to the user. When doing that, we’ve extended the built-in FileInterceptor and implemented filtering. There are still ways to extend the code from this article. Feel free to implement file deleting and use transactions as described in the 15th part of this series.
Thanks to learning about various ways of storing files, you are now free to compare the advantages and disadvantages and use an approach to suit your needs best.
Great tutorial! What about a tutorial on how to do Push Notifications when certain events happen in the API?
Nice,do Push Notifications when certain events happen in the API?
Fortunately, NestJS makes it very easy to store the files on the server. We need to pass additional arguments to the FileInterceptor.
users.service.tsusers.controller.tsAny chance to get an article about implementing file-type library in this article?
What kind of relation should I make when I want the entity to have multiple files? f.e – gallery of photos, etc.
thank you very much! the best tutorial, somehow you catch themes, which are not covered in other documentations and occur in real applications very often