- 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
With NestJS, we have quite a few transport layer implementations prepared for microservices. Among them, the gRPC transporter is definitely one of the most interesting. In this article, we explore the idea and implement it with NestJS.
gRPC is, at its core, a Remote Procedure Call (RPC) framework. Its main idea revolves around creating services in the form of functions that we can call remotely. It’s open-source and developed by Google. The gRPC framework is language-agnostic. Therefore, we can use it for communication across microservices using multiple programming languages.
The gRPC clients can directly call a method specified on a server. To describe the interface of the service and the payload messages, we use the protocol buffers. It is an efficient binary message format. It serializes very quickly and results in small messages.
Creating a .proto file
A first step to use gRPC is to create a .proto file using the protocol buffer language. This article uses the microservice that we’ve created in one of the previous parts of this series. Let’s break down the creation of the .proto step by step.
We’ll start by defining the version of the protocol buffers language. While there are some advantages and drawbacks to both, in this article, we use proto3.
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syntax = "proto3"; |
We also want to use the package keyword with a name. We will later refer to it when setting up gRPC with NestJS.
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package subscribers; |
The .proto file’s job is to describe the service and the methods we want to use remotely.
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service SubscribersService { rpc GetAllSubscribers (GetAllSubscribersParams) returns (SubscribersResponse) {} rpc AddSubscriber (CreateSubscriberDto) returns (Subscriber) {} } |
Even though we don’t need any parameters for the GetAllSubscribers method, we need to specify some message here – even if it is empty.
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message GetAllSubscribersParams {} |
Assigning types and numbers to fields
Another important thing is to define our Subscriber.
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message Subscriber { int32 id = 1; string email = 2; string name = 3; } message CreateSubscriberDto { string email = 1; string name = 2; } |
Above, we use fundamental field types: integer and strings. There are various types that we can assign to fields. For a full list, visit the official documentation.
A more interesting topic is assigning field numbers. Every field in a massage needs a unique number. The gRPC framework uses the numbers to identify the fields in the message binary format.
Deep knowledge of the gRPC encoding is not needed to start working with the framework. Although, it is important to know that field numbers from 1 to 15 take just one byte to encode the field number and the type. If the field number is 16 and bigger, it takes two bytes. Therefore, we should keep the smaller number for parameters that frequently occur in our messages. We might even want to leave some room in the range of 1 through 15 to add new parameters here later.
Changing the name of the field does not affect the protocol buffer encoding. Changing the number assigned to property does break the compatibility between applications, so we need to watch out for that.
Dealing with arrays
The GetAllSubscribers method is supposed to return an array. Unfortunately, there is no straightforward way for our gRPC methods to return an array (other than a stream). Therefore, we create a GetAllSubscribers method that returns an object with the data property.
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message SubscribersResponse { repeated Subscriber data = 1; } |
The repeated keyword means that this field can be repeated any number of times.
Using gRPC with NestJS
Aside from installing the @nestjs/microservices package, we also need the following:
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npm install grpc @grpc/proto-loader |
Defining the microservice
For starters, let’s start with defining our microservice. Here, we need three things:
- the package’s name that we’ve defined in our .proto file,
- the path to the .proto file,
- the connection URL – defaults to localhost:5000.
main.ts
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import { NestFactory } from '@nestjs/core'; import { AppModule } from './app.module'; import { MicroserviceOptions, Transport } from '@nestjs/microservices'; import { join } from 'path'; import { ConfigService } from '@nestjs/config'; async function bootstrap() { const app = await NestFactory.create(AppModule); const configService = app.get(ConfigService); await app.connectMicroservice<MicroserviceOptions>({ transport: Transport.GRPC, options: { package: 'subscribers', protoPath: join(process.cwd(), 'src/subscribers/subscribers.proto'), url: configService.get('GRPC_CONNECTION_URL') }, }); app.startAllMicroservices(); } bootstrap(); |
It is worth mentioning that, by default, our build process does not copy the .proto files to the dist directory. Therefore, in my configuration, I point to the subscribers.proto in the src directory. Another approach would be to create a proto directory at the top of our project. We could also create a script that copies the .proto files to dist.
Running the above code initiates a gRPC server under the hood that can be accessed by the provided URL.
If we look under the hood, we can see that NestJS creates an instance of the grpc.Server class and begins handling requests. You can read more about it here.
In this article, we store the URL in our .env file:
.env
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GRPC_CONNECTION_URL=localhost:5000 # ... |
With gRPC, we don’t use the @MessagePattern() decorator anymore. Instead, we mark our functions using the @GrpcMethod().
subscribers.service.ts
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import { Controller } from '@nestjs/common'; import { InjectRepository } from '@nestjs/typeorm'; import Subscriber from './subscriber.entity'; import CreateSubscriberDto from './dto/createSubscriber.dto'; import { Repository } from 'typeorm'; import { GrpcMethod } from '@nestjs/microservices'; @Controller() export class SubscribersService { constructor( @InjectRepository(Subscriber) private subscribersRepository: Repository<Subscriber>, ) {} @GrpcMethod() async addSubscriber(subscriber: CreateSubscriberDto) { const newSubscriber = await this.subscribersRepository.create(subscriber); await this.subscribersRepository.save(newSubscriber); return newSubscriber; } @GrpcMethod() async getAllSubscribers() { const data = await this.subscribersRepository.find(); return { data } } } |
Please note that we don’t have the subscribers.controller.ts anymore. This time, we only have the SubscribersService that we mark with the @Controller() decorator. It works thanks to the fact that it matches the name of the service in the .proto file. We also add it to the controllers array in our SubscribersModule:
subscribers.module.ts
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import { Module } from '@nestjs/common'; import { TypeOrmModule } from '@nestjs/typeorm'; import Subscriber from './subscriber.entity'; import { SubscribersService } from './subscribers.service'; @Module({ imports: [TypeOrmModule.forFeature([Subscriber])], exports: [], controllers: [SubscribersService], }) export class SubscribersModule {} |
There are other ways to define a gRPC service with NestJS with additional arguments passed to the @GrpcMethod() decorator. If you want to know more, check out the documentation.
Creating a client
Once we have the microservice ready, we can connect to it from a client. The first thing to realize is that we need the same .proto for the client also. We also need the same environment variable that we’ve called GRPC_CONNECTION_URL.
subscribers.module.ts
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import { Module } from '@nestjs/common'; import SubscribersController from './subscribers.controller'; import { ConfigModule, ConfigService } from '@nestjs/config'; import { ClientProxyFactory, Transport } from '@nestjs/microservices'; import { join } from "path"; @Module({ imports: [ConfigModule], controllers: [SubscribersController], providers: [ { provide: 'SUBSCRIBERS_PACKAGE', useFactory: (configService: ConfigService) => { return ClientProxyFactory.create({ transport: Transport.GRPC, options: { package: 'subscribers', protoPath: join(process.cwd(), 'src/subscribers/subscribers.proto'), url: configService.get('GRPC_CONNECTION_URL') }, }) }, inject: [ConfigService], } ], }) export class SubscribersModule {} |
Since the SubscribersService is in another application, we need to create an interface to use it.
subscribers.service.interface.ts
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import CreateSubscriberDto from './dto/createSubscriber.dto'; import Subscriber from './subscriber.service'; interface SubscribersService { addSubscriber(subscriber: CreateSubscriberDto): Promise<Subscriber> getAllSubscribers(params: {}): Promise<{data: Subscriber[]}> } export default SubscribersService; |
Please note that we expect an empty object to be passed to the getAllSubscribers method because, with gRPC, we need to have some sorts of parameters. Even if they are empty.
Once we’ve registered our microservice, we can inject it into a controller. To use our remote service, we need to use the onModuleInit method that NestJS calls once it resolves all of its dependencies.
subscribers.controller.ts
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import { Body, Controller, Get, Post, UseGuards, UseInterceptors, ClassSerializerInterceptor, Inject, OnModuleInit, } from '@nestjs/common'; import JwtAuthenticationGuard from '../authentication/jwt-authentication.guard'; import CreateSubscriberDto from './dto/createSubscriber.dto'; import { ClientGrpc } from '@nestjs/microservices'; import SubscribersService from './subscribers.service.interface'; @Controller('subscribers') @UseInterceptors(ClassSerializerInterceptor) export default class SubscribersController implements OnModuleInit { private subscribersService: SubscribersService; constructor(@Inject('SUBSCRIBERS_PACKAGE') private client: ClientGrpc) {} onModuleInit() { this.subscribersService = this.client.getService<SubscribersService>('SubscribersService'); } @Get() async getSubscribers() { return this.subscribersService.getAllSubscribers({}); } @Post() @UseGuards(JwtAuthenticationGuard) async createPost(@Body() subscriber: CreateSubscriberDto) { return this.subscribersService.addSubscriber(subscriber); } } |
With all of the above, we have a working connection with our microservice!
Summary
In this article, we’ve looked into the basics of establishing a gRPC connection with NestJS. This covered the fundamentals of the gRPC framework and Protocol Buffers language. We’ve also looked under to hood of NestJS to understand better what it does. Thanks to doing all of that, we learned about yet another transporter that we can use to communicate with our microservices.
Marcin, it is a great job that you are doing here! Really appreciate it 🙂 one question though: are you planning also to deploy that project to ‘production’ somewhere(AWS,Google Cloud, etc.)? Is that process rather complicated ? What would be the best option to deploy such project?
Best,
Hi,
If I am not mistaken for this to work you have to define both Subscriber and CreateSubscriberDto in both the client and the server. Doesn’t this break SOLID principles you mention in another article?
The latest version of Nest requires you to include the @grpc/grpc-js package as well.
I have followed all of these instructions but when I send a request I get the following error:
Any help though?