- 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
Debugging is a great way to find issues when running an application locally. Unfortunately, we don’t have this option in a deployed application. Because of that, implementing logging functionality is necessary to track down and investigate any potential problems. In this article, we learn how to use the logger built into NestJS and integrate it with the Drizzle ORM.
Logger built into NestJS
NestJS conveniently offers built-in logging functionalities that we can use. Each message that we log needs to have a level. Here is a breakdown of all log levels, sorted by severity:
- fatal
- error
- warn
- log
- debug
- verbose
NestJS added the “fatal” log level some time last year.
To create logs, we should use the Logger class. One way to do that is to import it from @nestjs/common.
articles.service.ts
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import { Injectable, NotFoundException, Logger } from '@nestjs/common'; import { DrizzleService } from '../database/drizzle.service'; import { databaseSchema } from '../database/database-schema'; import { eq } from 'drizzle-orm'; @Injectable() export class ArticlesService { constructor(private readonly drizzleService: DrizzleService) {} async getById(id: number) { const articles = await this.drizzleService.db .select() .from(databaseSchema.articles) .where(eq(databaseSchema.articles.id, id)); const article = articles.pop(); if (!article) { Logger.warn('Tried to get an article that does not exist'); throw new NotFoundException(); } return article; } // ... } |
Although the above approach does the job, the official documentation recommends creating an instance of the logger inside each class that uses it.
articles.service.ts
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import { Injectable, NotFoundException, Logger } from '@nestjs/common'; import { DrizzleService } from '../database/drizzle.service'; import { databaseSchema } from '../database/database-schema'; import { eq } from 'drizzle-orm'; @Injectable() export class ArticlesService { private readonly logger = new Logger(ArticlesService.name); constructor(private readonly drizzleService: DrizzleService) {} async getById(id: number) { const articles = await this.drizzleService.db .select() .from(databaseSchema.articles) .where(eq(databaseSchema.articles.id, id)); const article = articles.pop(); if (!article) { this.logger.warn('Tried to get an article that does not exist'); throw new NotFoundException(); } return article; } // ... } |
With this adjustment, NestJS can include the name of our service in the log, which makes it easier to read.
Working with log levels
The higher the level of our log is, the higher the severity. For instance, if a user attempts to access an article that does not exist, it likely shouldn’t cause an alarm in the middle of the night. Because of that, in our example above, we used warn instead of error. The higher the log, the more concerned we should be.
To avoid cluttering our logs, we can filter some of them out.
main.ts
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import { NestFactory } from '@nestjs/core'; import { AppModule } from './app.module'; import { LogLevel, ValidationPipe } from '@nestjs/common'; async function bootstrap() { const isProduction = process.env.NODE_ENV === 'production'; const logLevels: LogLevel[] = isProduction ? ['fatal', 'error', 'warn', 'log'] : ['fatal', 'error', 'warn', 'log', 'debug', 'verbose']; const app = await NestFactory.create(AppModule, { logger: logLevels, }); app.useGlobalPipes(new ValidationPipe({ whitelist: true })); await app.listen(3000); } bootstrap(); |
A surprising thing is that providing just ['verbose'] turns on all log levels. When we take a look at the isLogLevelEnabled function under the hood of NestJS, we can see that searches for the looks for the highest severity included in our array and turns on the logs with the lower severity as well. However, we provide the complete array for readability.
Logging SQL queries with the Drizzle ORM
Logging SQL queries allows us to investigate how Drizzle ORM interacts with our database and notice potential issues.
The most straightforward way to start logging our SQL queries is to pass an additional parameter to the drizzle function.
drizzle.service.ts
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import { Inject, Injectable } from '@nestjs/common'; import { Pool } from 'pg'; import { CONNECTION_POOL } from './database.module-definition'; import { drizzle, NodePgDatabase } from 'drizzle-orm/node-postgres'; import { databaseSchema } from './database-schema'; @Injectable() export class DrizzleService { public db: NodePgDatabase<typeof databaseSchema>; constructor(@Inject(CONNECTION_POOL) private readonly pool: Pool) { this.db = drizzle(this.pool, { schema: databaseSchema, logger: true }); } } |
The downside to this solution is that the output of the default Drizzle ORM logger looks different from that of the NestJS logger. Let’s deal with that by creating a custom Drizzle ORM logger.
custom-drizzle-logger.ts
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import { Logger as NestLogger } from '@nestjs/common'; import { Logger } from 'drizzle-orm/logger'; export class CustomDrizzleLogger implements Logger { private readonly logger = new NestLogger('SQL'); logQuery(query: string, params: unknown[]): void { this.logger.log(`${query} | Params: ${JSON.stringify(params)}`); } } |
Every time Drizzle ORM wants to log a query, it calls the logQuery function. We can take advantage of that by using the NestJS logger.
We can now use our custom logger instead of the default one built into the Drizzle ORM.
drizzle-service.ts
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import { Inject, Injectable } from '@nestjs/common'; import { Pool } from 'pg'; import { CONNECTION_POOL } from './database.module-definition'; import { drizzle, NodePgDatabase } from 'drizzle-orm/node-postgres'; import { databaseSchema } from './database-schema'; import { CustomDrizzleLogger } from './custom-drizzle-logger'; @Injectable() export class DrizzleService { public db: NodePgDatabase<typeof databaseSchema>; constructor(@Inject(CONNECTION_POOL) private readonly pool: Pool) { this.db = drizzle(this.pool, { schema: databaseSchema, logger: new CustomDrizzleLogger(), }); } } |
Thanks to this solution, our logs are a lot more consistent.
Using a logging interceptor
Manually defining logs for every case in our application might produce the best results but can be time-consuming. To automate our logs somewhat, we can write a NestJS interceptor that handles logging automatically.
Interceptors in NestJS allow us run additional logic before or after NestJS handles a particular API request.
logger.interceptor.ts
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import { Injectable, NestInterceptor, ExecutionContext, CallHandler, Logger, } from '@nestjs/common'; import { Request, Response } from 'express'; @Injectable() export class LoggerInterceptor implements NestInterceptor { private readonly logger = new Logger('HTTP'); intercept(context: ExecutionContext, next: CallHandler) { const httpContext = context.switchToHttp(); const request = httpContext.getRequest<Request>(); const response = httpContext.getResponse<Response>(); response.on('finish', () => { const { method, originalUrl } = request; const { statusCode, statusMessage } = response; const message = `${method} ${originalUrl} ${statusCode} ${statusMessage}`; if (statusCode >= 500) { return this.logger.error(message); } if (statusCode >= 400) { return this.logger.warn(message); } return this.logger.log(message); }); return next.handle(); } } |
You can add more data into the logs such as the POST request body.
Above, we wait for the HTTP request to complete and then determine the log level based on the status code of our response.
There is more than one way to use our interceptor. For example, we can decorate a single method with it.
articles.controller.ts
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import { Controller, Get, Param, ParseIntPipe, UseInterceptors, } from '@nestjs/common'; import { ArticlesService } from './articles.service'; import { LoggerInterceptor } from '../utilities/logger.interceptor'; @Controller('articles') export class ArticlesController { constructor(private readonly articlesService: ArticlesService) {} @Get(':id') @UseInterceptors(LoggerInterceptor) getById(@Param('id', ParseIntPipe) id: number) { return this.articlesService.getById(id); } // ... } |
Another approach is to decorate the entire controller.
articles.controller.ts
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import { Controller, UseInterceptors } from '@nestjs/common'; import { LoggerInterceptor } from '../utilities/logger.interceptor'; @Controller('articles') @UseInterceptors(LoggerInterceptor) export class ArticlesController { // ... } |
We can also use the useGlobalInterceptors function to apply our interceptor to all our controllers.
main.ts
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import { NestFactory } from '@nestjs/core'; import { AppModule } from './app.module'; import { LogLevel, ValidationPipe } from '@nestjs/common'; import { LoggerInterceptor } from './utilities/logger.interceptor'; async function bootstrap() { const isProduction = process.env.NODE_ENV === 'production'; const logLevels: LogLevel[] = isProduction ? ['fatal', 'error', 'warn', 'log'] : ['fatal', 'error', 'warn', 'log', 'debug', 'verbose']; const app = await NestFactory.create(AppModule, { logger: logLevels, }); app.useGlobalInterceptors(new LoggerInterceptor()); app.useGlobalPipes(new ValidationPipe({ whitelist: true })); await app.listen(3000); } bootstrap(); |
Summary
In this article, we explored how to use the built-in NestJS logger in a few different ways. Thanks to our approach, we can automatically log all SQL queries that Drizzle ORM makes and the HTTP responses our NestJS application sends. Besides that, we can also implement custom logging if necessary. To implement that, we had to create a custom interceptor that logs various messages automatically when our NestJS application sends a response. We also made a custom Drizzle ORM logger and combined it with the logger built into NestJS.
By adopting a thorough approach to logging, troubleshooting issues becomes significantly easier. It makes it a valuable thing to learn and implement in your NestJS application.
Hey Wanago, thanks for article.
I hope you can create a seri about microservices with nest.js.
That topic is very hard and interesting!
Hi! You can check out those articles:
API with NestJS #18. Exploring the idea of microservices
API with NestJS #19. Using RabbitMQ to communicate with microservices
API with NestJS #20. Communicating with microservices using the gRPC framework