CustomLogger

The main logger service implementing NestJS LoggerService and ILogger interface.

Import

import { CustomLogger } from '@shinijs/logger';

Usage

import { Injectable } from '@nestjs/common';
import { CustomLogger } from '@shinijs/logger';

@Injectable()
export class MyService {
  constructor(private readonly logger: CustomLogger) {
    this.logger.setContext('MyService');
  }
}

Methods

setContext(context: string): void

Sets the default context for all log messages.

Parameters:

• context - The context name (e.g., service name)

Example:

this.logger.setContext('UserService');
this.logger.log('User created'); // Context: 'UserService'

getContext(): string

Gets the current context.

Returns: The current context string

Example:

const context = this.logger.getContext(); // 'UserService'

log(message: string, context?: string): void

Logs an informational message. Alias for info().

Parameters:

• message - The log message
• context - Optional context override

Example:

this.logger.log('User created', 'UserService');
// or
this.logger.log('User created'); // Uses default context

info(message: string, meta?: Record<string, unknown>, context?: LogContext): void

Logs an informational message with optional metadata.

Parameters:

• message - The log message
• meta - Optional metadata object
• context - Optional context (string or object)

Example:

this.logger.info('User created', {
  userId: '123',
  email: 'user@example.com',
});

error(message: string, error?: Error | unknown, context?: LogContext): void

Logs an error message with optional error object.

Parameters:

• message - The error message
• error - Optional Error object or error data
• context - Optional context (string or object)

Example:

try {
  await someOperation();
} catch (error) {
  this.logger.error('Operation failed', error, {
    operation: 'someOperation',
  });
}

warn(message: string, meta?: Record<string, unknown>, context?: LogContext): void

Logs a warning message with optional metadata.

Parameters:

• message - The warning message
• meta - Optional metadata object
• context - Optional context (string or object)

Example:

this.logger.warn('Rate limit approaching', {
  current: 90,
  limit: 100,
});

debug(message: string, meta?: Record<string, unknown>, context?: LogContext): void

Logs a debug message with optional metadata.

Parameters:

• message - The debug message
• meta - Optional metadata object
• context - Optional context (string or object)

Example:

this.logger.debug('Processing step', {
  step: 1,
  data: someData,
});

verbose(message: string, meta?: Record<string, unknown>, context?: LogContext): void

Logs a verbose/trace message with optional metadata.

Parameters:

• message - The verbose message
• meta - Optional metadata object
• context - Optional context (string or object)

Example:

this.logger.verbose('Detailed trace info', {
  internalState: state,
});

fatal(message: string, meta?: Record<string, unknown>, context?: LogContext): void

Logs a fatal error message with optional metadata.

Parameters:

• message - The fatal error message
• meta - Optional metadata object
• context - Optional context (string or object)

Example:

this.logger.fatal('Application cannot start', {
  reason: 'Database connection failed',
  error: connectionError,
});

Context Types

The context parameter can be:

1. String - Simple context name

   this.logger.info('Message', {}, 'MyService');

2. LogContextObject - Rich context object

   this.logger.info('Message', {}, {
     requestId: 'req-123',
     userId: 'user-456',
     method: 'POST',
     url: '/api/users',
   });

NestJS LoggerService Compatibility

CustomLogger implements NestJS LoggerService, so it can be used as a drop-in replacement:

import { LoggerService } from '@nestjs/common';

// CustomLogger implements LoggerService
const logger: LoggerService = customLogger;

logger.log('Message');
logger.error('Error', 'Trace');
logger.warn('Warning');
logger.debug('Debug');
logger.verbose('Verbose');

See Also

• ILogger Interface - Logger interface definition
• LoggerFactory - Create context-bound loggers
• Examples - Usage examples