@denis_softdoes/logger

Structured pino logger with request-scoped context propagation, recursive masking and optional rotating file output.

Features

• JSON logs to stdout by default
• Optional rotating file logs
• AsyncLocalStorage helpers for requestId, traceId, userId, tenantId
• Recursive masking with circular reference protection
• Safe Error serialization
• TypeScript-first API

Install

npm install @denis_softdoes/logger

Basic Usage

import { createLogger } from '@denis_softdoes/logger';

const logger = createLogger('billing-service');

logger.info('Invoice created', {
  invoiceId: 42,
  customerEmail: '[email protected]',
});

Request Context

import { createLogger, runWithLogContext } from '@denis_softdoes/logger';

const logger = createLogger('api');

runWithLogContext({ requestId: 'REQ-1', traceId: 'TRACE-1' }, () => {
  logger.info('Request started');
});

NestJS Integration

import {
  createLogger,
  createNestLoggerService,
} from '@denis_softdoes/logger';

const logger = createLogger('api');
const nestLogger = createNestLoggerService(logger);

app.useLogger(nestLogger);

Configuration

import { createLogger } from '@denis_softdoes/logger';

const logger = createLogger('api', {
  level: 'debug',
  masks: ['ssn'],
  console: { enabled: true },
  file: {
    enabled: true,
    dir: 'logs',
    fileName: 'app.log',
    errorFileName: 'error.log',
    maxSize: '10M',
    maxFiles: 7,
  },
});

Environment variables:

• LOG_LEVEL
• LOG_TO_FILE
• LOG_DIR
• LOG_FILE_NAME
• LOG_ERROR_FILE_NAME
• LOG_FILE_MAX_SIZE
• LOG_FILE_MAX_FILES

Notes

• File logging is opt-in.
• Masked fields are matched case-insensitively.
• Arrays, nested objects and Error instances are handled safely.