- 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
So far in this series, we’ve defined many different modules that can group provides and controllers. None of them was customizable, though. In this article, we learn how to create dynamic modules that are customizable, making them easier to reuse. While doing that, we rewrite some of our old code to use dynamic modules.
If you want to know more about modules in general, check out API with NestJS #6. Looking into dependency injection and modules
To better illustrate why we might want to use dynamic modules, let’s look at the EmailModule we’ve defined in the API with NestJS #25. Sending scheduled emails with cron and Nodemailer article.
email.module.ts
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import { Module } from '@nestjs/common'; import EmailService from './email.service'; import { ConfigModule } from '@nestjs/config'; @Module({ imports: [ConfigModule], controllers: [], providers: [EmailService], exports: [EmailService], }) export class EmailModule {} |
The above module contains the EmailService provider and exports it. Let’s look under the hood:
email.service.ts
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import { Injectable } from '@nestjs/common'; import { createTransport } from 'nodemailer'; import * as Mail from 'nodemailer/lib/mailer'; import { ConfigService } from '@nestjs/config'; @Injectable() export default class EmailService { private nodemailerTransport: Mail; constructor(private readonly configService: ConfigService) { this.nodemailerTransport = createTransport({ service: configService.get('EMAIL_SERVICE'), auth: { user: configService.get('EMAIL_USER'), pass: configService.get('EMAIL_PASSWORD'), }, }); } sendMail(options: Mail.Options) { return this.nodemailerTransport.sendMail(options); } } |
The crucial thing to notice above is that our EmailService will always have the same configuration. So, for example, we can’t have a separate email for password confirmation and a separate email for the newsletter. To deal with this issue, we can create a dynamic module.
Creating a dynamic module
To create a dynamic module, let’s add a static method to the EmailModule.
email.module.ts
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import { DynamicModule, Module } from '@nestjs/common'; import EmailService from './email.service'; import { EMAIL_CONFIG_OPTIONS } from './constants'; import EmailOptions from './emailOptions.interface'; @Module({}) export class EmailModule { static register(options: EmailOptions): DynamicModule { return { module: EmailModule, providers: [ { provide: EMAIL_CONFIG_OPTIONS, useValue: options, }, EmailService, ], exports: [EmailService], }; } } |
Above, instead of putting our module definition inside the @Module({}) decorator, we return it from the register method. We allow the user to provide the EmailOptions as the argument to the register function.
emailOptions.interface.ts
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interface EmailOptions { service: string; user: string; password: string; } export default EmailOptions; |
We also define a unique EMAIL_CONFIG_OPTIONS constant in a separate file.
constants.ts
1 |
export const EMAIL_CONFIG_OPTIONS = 'EMAIL_CONFIG_OPTIONS'; |
We can also use a Symbol.
In the register() method, we add the EMAIL_CONFIG_OPTIONS to the list of providers along with the option’s value. Thanks to the above, the configuration will be available in the EmailService through the @Inject() decorator.
email.service.ts
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import { Inject, Injectable } from '@nestjs/common'; import { createTransport } from 'nodemailer'; import { EMAIL_CONFIG_OPTIONS } from './constants'; import Mail from 'nodemailer/lib/mailer'; import EmailOptions from './emailOptions.interface'; @Injectable() export default class EmailService { private nodemailerTransport: Mail; constructor(@Inject(EMAIL_CONFIG_OPTIONS) private options: EmailOptions) { this.nodemailerTransport = createTransport({ service: options.service, auth: { user: options.user, pass: options.password, }, }); } sendMail(options: Mail.Options) { return this.nodemailerTransport.sendMail(options); } } |
Thanks to our approach, we can now configure the module when importing it.
emailConfirmation.module.ts
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import { Module } from '@nestjs/common'; import { EmailConfirmationService } from './emailConfirmation.service'; import { ConfigModule } from '@nestjs/config'; import { EmailModule } from '../email/email.module'; import { JwtModule } from '@nestjs/jwt'; import { EmailConfirmationController } from './emailConfirmation.controller'; import { UsersModule } from '../users/users.module'; @Module({ imports: [ ConfigModule, EmailModule.register({ service: 'gmail', user: 'email.account@gmail.com', password: 'mystrongpassword', }), JwtModule.register({}), UsersModule, ], providers: [EmailConfirmationService], exports: [EmailConfirmationService], controllers: [EmailConfirmationController], }) export class EmailConfirmationModule {} |
Asynchronous configuration
There is a significant drawback to the above approach because we no longer can use the ConfigService when setting up our email provider. Fortunately, we can deal with this issue by creating an asynchronous version of our register method. It will have access to the dependency injection mechanism built into NestJS.
Our registerAsync method will also receive the options, but the type used for its argument is slightly different than register.
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EmailModule.registerAsync({ imports: [ConfigModule], inject: [ConfigService], useFactory: (configService: ConfigService) => ({ service: configService.get('EMAIL_SERVICE'), user: configService.get('EMAIL_USER'), password: configService.get('EMAIL_PASSWORD'), }), }), |
Let’s go through all of the properties above:
- imports – a list of modules we want the EmailModule to import because we need them in useFactory,
- inject – a list of providers we want NestJS to inject into the context of the useFactory function,
- useFactory – a function that returns the value for our EMAIL_CONFIG_OPTIONS provider.
A straightforward way to create a type with the above properties is to use the ModuleMetadata and FactoryProvider interfaces.
emailOptions.type.ts
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import { ModuleMetadata } from '@nestjs/common'; import EmailOptions from './emailOptions.interface'; import { FactoryProvider } from '@nestjs/common/interfaces/modules/provider.interface'; type EmailAsyncOptions = Pick<ModuleMetadata, 'imports'> & Pick<FactoryProvider<EmailOptions>, 'useFactory' | 'inject'>; export default EmailAsyncOptions; |
Please notice that FactoryProvider is generic and we pass EmailOptions to it to enforce the correct configuration.
Once we have the above, we can define our registerAsync method.
email.module.ts
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import { DynamicModule, Module } from '@nestjs/common'; import EmailService from './email.service'; import { EMAIL_CONFIG_OPTIONS } from './constants'; import EmailOptions from './emailOptions.interface'; import EmailAsyncOptions from './emailAsyncOptions.type'; @Module({}) export class EmailModule { static register(options: EmailOptions): DynamicModule { return { module: EmailModule, providers: [ { provide: EMAIL_CONFIG_OPTIONS, useValue: options, }, EmailService, ], exports: [EmailService], }; } static registerAsync(options: EmailAsyncOptions): DynamicModule { return { module: EmailModule, imports: options.imports, providers: [ { provide: EMAIL_CONFIG_OPTIONS, useFactory: options.useFactory, inject: options.inject, }, EmailService, ], exports: [EmailService], }; } } |
Under the hood, our registerAsync method is very similar to register. The difference is that it uses useFactory and inject instead of useValue. It also accepts an array of additional modules to import through options.imports.
Thanks to creating a way to configure the EmailModule asynchronously, we can now use it with various configurations depending on the use case and still use the dependency injection mechanism.
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EmailModule.registerAsync({ imports: [ConfigModule], inject: [ConfigService], useFactory: (configService: ConfigService) => ({ service: configService.get('NEWSLETTER_EMAIL_SERVICE'), user: configService.get('NEWSLETTER_EMAIL_USER'), password: configService.get('NEWSLETTER_EMAIL_PASSWORD'), }), }), |
Naming conventions
So far, we’ve only defined the register and registerAsync methods. It is significant to notice that NestJS doesn’t enforce any naming conventions but has some guidelines.
register and registerAsync
The register and registerAsync methods we’ve used in this article so far are supposed to configure a module for use only with the module that imports it.
To illustrate it, let’s look at the EmailSchedulingModule.
emailScheduling.module.ts
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import { Module } from '@nestjs/common'; import EmailSchedulingService from './emailScheduling.service'; import { EmailModule } from '../email/email.module'; import EmailSchedulingController from './emailScheduling.controller'; import { ConfigModule, ConfigService } from '@nestjs/config'; @Module({ imports: [ EmailModule.registerAsync({ imports: [ConfigModule], inject: [ConfigService], useFactory: (configService: ConfigService) => ({ service: configService.get('EMAIL_SERVICE'), user: configService.get('EMAIL_USER'), password: configService.get('EMAIL_PASSWORD'), }), }), ], controllers: [EmailSchedulingController], providers: [EmailSchedulingService], }) export class EmailSchedulingModule {} |
Above, we provide the configuration for the EmailModule that we only want to use in the EmailSchedulingModule.
forRoot and forRootAsync
With forRoot and forRootAsync methods, we aim to configure a dynamic module once and reuse this configuration in multiple places. Therefore, it makes a lot of sense with global modules.
A great example is the TypeOrmModule module provided by NestJS.
database.module.ts
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import { Module } from '@nestjs/common'; import { TypeOrmModule } from '@nestjs/typeorm'; import { ConfigModule, ConfigService } from '@nestjs/config'; import Address from '../users/address.entity'; @Module({ imports: [ TypeOrmModule.forRootAsync({ imports: [ConfigModule], inject: [ConfigService], useFactory: (configService: ConfigService) => ({ type: 'postgres', username: configService.get('POSTGRES_USER'), password: configService.get('POSTGRES_PASSWORD'), entities: [Address], autoLoadEntities: true, // ... }), }), ], }) export class DatabaseModule {} |
forFeature and forFeatureAsync
With the forFeature and forFeatureAsync methods, we can alter the configuration specified using forRootAsync. Again, a good example is the TypeOrmModule.
categories.module.ts
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import { Module } from '@nestjs/common'; import CategoriesController from './categories.controller'; import CategoriesService from './categories.service'; import Category from './category.entity'; import { TypeOrmModule } from '@nestjs/typeorm'; @Module({ imports: [TypeOrmModule.forFeature([Category])], controllers: [CategoriesController], providers: [CategoriesService], }) export class CategoriesModule {} |
Above, we specify additional configuration using forFeature() that’s applicable only in the CategoriesModule.
Configurable module builder
Configuring a dynamic module can be difficult, especially with the asynchronous methods. Fortunately, NestJS has a ConfigurableModuleBuilder class that does much of the work for us. To use it, let’s create a separate file.
email.module-definition.ts
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import { ConfigurableModuleBuilder } from '@nestjs/common'; import EmailOptions from './emailOptions.interface'; export const { ConfigurableModuleClass: ConfigurableEmailModule, MODULE_OPTIONS_TOKEN: EMAIL_CONFIG_OPTIONS, } = new ConfigurableModuleBuilder<EmailOptions>().build(); |
Now, we need our EmailModule to extend the ConfigurableEmailModule class.
email.module.ts
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import { Module } from '@nestjs/common'; import { ConfigurableEmailModule } from './email.module-definition'; import EmailService from './email.service'; @Module({ providers: [EmailService], exports: [EmailService], }) export class EmailModule extends ConfigurableEmailModule {} |
Thanks to the above, our EmailModule allows us to use both register and registerAsync classes.
For it to work as expected, we need to remember to use the EMAIL_CONFIG_OPTIONS constant that we got from the email.module-definition.ts file.
Extending auto-generated methods
If we need additional logic, we can extend the auto-generated methods. When doing that, the ConfigurableModuleAsyncOptions can come in handy.
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import { ConfigurableModuleAsyncOptions, DynamicModule, Module } from '@nestjs/common'; import { ConfigurableEmailModule } from './email.module-definition'; import EmailService from './email.service'; import EmailOptions from './emailOptions.interface'; @Module({ providers: [EmailService], exports: [EmailService], }) export class EmailModule extends ConfigurableEmailModule { static register(options: EmailOptions): DynamicModule { return { // you can put additional configuration here ...super.register(options), }; } static registerAsync(options: ConfigurableModuleAsyncOptions<EmailOptions>): DynamicModule { return { // you can put additional configuration here ...super.registerAsync(options), }; } } |
Using methods other than register and registerAsync
If we want to use methods other than register and registerAsync, we need to call the setClassMethodName function.
email.module-definition.ts
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import { ConfigurableModuleBuilder } from '@nestjs/common'; import EmailOptions from './emailOptions.interface'; export const { ConfigurableModuleClass: ConfigurableEmailModule, MODULE_OPTIONS_TOKEN: EMAIL_CONFIG_OPTIONS, } = new ConfigurableModuleBuilder<EmailOptions>() .setClassMethodName('forRoot') .build(); |
Summary
In this article, we’ve gone through the idea of dynamic modules. To illustrate it, we implemented it manually and learned how it works under the hood. Then, we’ve learned how to use utilities built into NestJS that can simplify this process significantly. Dynamic modules are a handy feature that allows us to make our modules customizable while taking advantage of the dependency injection mechanism.
Thank you!
Thank you
Thank you!