@origins-digital/logger

A comprehensive logging package for NestJS applications using Winston.

Installation

npm install @origins-digital/logger

Features

• Winston-based logging with JSON formatting
• Request logging middleware
• Configurable log levels
• Environment-specific formatting (local vs production)
• Automatic stack trace inclusion
• Request/response metadata logging
• Sensitive data filtering

Usage

Basic Setup

import { Module } from '@nestjs/common';
import { LoggerModule } from 'nestjs-winston';
import { LoggerConfig } from '@origins-digital/logger';

@Module({
  imports: [LoggerModule.forRoot(LoggerConfig.instance().loggerOptions())],
})
export class AppModule {}

Using the Logger

import { Controller, Get } from '@nestjs/common';
import { Logger } from '@nestjs/common';
import { LoggerMiddleware } from '@origins-digital/logger';

@Controller('example')
export class ExampleController {
  private readonly logger = new Logger(ExampleController.name);

  @Get()
  getExample() {
    this.logger.log('This is an info message');
    this.logger.debug('This is a debug message');
    this.logger.warn('This is a warning message');
    this.logger.error(
      'This is an error message',
      new Error('Something went wrong'),
    );

    return { message: 'Example response' };
  }
}

Request Logging Middleware

import { Module, NestModule, MiddlewareConsumer } from '@nestjs/common';
import { LoggerMiddleware } from '@origins-digital/logger';

@Module({})
export class AppModule implements NestModule {
  configure(consumer: MiddlewareConsumer) {
    consumer.apply(LoggerMiddleware).forRoutes('*');
  }
}

Log Levels

The package supports the following log levels:

• silly (5)
• debug (4)
• verbose (3)
• info (2) - Default
• warn (1)
• error (0)

You can configure the log level using the LOG_LEVEL environment variable, either by name or number.

Log Format

Production Format

{
  "timestamp": "2024-03-21 10:30:45:123",
  "level": "info",
  "message": "Example message",
  "context": "ExampleController",
  "meta": {
    "key": "value"
  }
}

Local Development Format

2024-03-21 10:30:45:123 [ExampleController] info: Example message {"key":"value"}

Request Logging

The middleware automatically logs:

• Request method and URL
• Request headers (excluding sensitive data)
• Request body (excluding sensitive data)
• Response status and timing
• Client information (IP, user agent, etc.)
• Error stack traces (if any)

Configuration

The logger can be configured through environment variables:

• LOG_LEVEL: Set the logging level (default: 'info')
• APP_ENV: Set the environment ('local' for colored output, 'production' for JSON)

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.