The built-in LoggingBehavior

The core package ships with LoggingBehavior that logs request/response data and timing metrics via the NestJS Logger:

import { LoggingBehavior } from '@nestjs-pipeline/core';

// Register globally with default options
PipelineModule.forRoot({
  globalBehaviors: { scope: 'all', before: [LoggingBehavior] },
})

Options (LoggingBehaviorOptions):

Option	Type	Default	Description
metricLogLevel	LogLevel | 'none'	'log'	Log level for timing/duration messages
requestResponseLogLevel	LogLevel | 'none'	'debug'	Log level for request/response payloads
errorLogLevel	LogLevel | 'none'	'error'	Log level when an error happened
mapLogLevel	Map<ErrorClass, LogLevel | 'none'>	undefined	Specific log levels mapped by exception error class (most specific match in prototype chain wins)
excludeKeys	string[]	[]	Keys to omit from request/response logs (supports dot notation for nested properties)
excludeRequestObj	boolean	true	If true, omits the request object from logs entirely (shows placeholder instead)
excludeResponseObj	boolean	true	If true, omits the response object from logs entirely (shows placeholder instead)
logFormat	'text' | 'structured'	'text'	Output shape for request/response/metric/error logs. 'text' produces a single interpolated string; 'structured' produces a plain object (e.g. { msg, request }), useful for structured loggers like nestjs-pino/pino that serialize to JSON

By default excludeRequestObj/excludeResponseObj are true, so out of the box you’ll see the placeholders [exclude request obj] / [exclude response obj] rather than the actual payload — set them to false to log the real request/response.

On failure, the error log also includes the thrown error’s stack (when it’s an Error instance) and, if the error exposes an optionalParams property (e.g. a custom exception carrying extra structured context), those values are appended to the log entry as well.

To provide your own logger implementation (for example nestjs-pino), bind the LOGGING_BEHAVIOR_LOGGER token:

import { Module } from '@nestjs/common';
import { NativeLogger } from 'nestjs-pino';
import {
  LOGGING_BEHAVIOR_LOGGER,
  LoggingBehavior,
  PipelineModule,
} from '@nestjs-pipeline/core';

@Module({
  imports: [
    PipelineModule.forRoot({
      globalBehaviors: { scope: 'all', before: [LoggingBehavior] },
      bootstrapLogLevel: 'verbose',
    }),
  ],
  providers: [
    { provide: LOGGING_BEHAVIOR_LOGGER, useExisting: NativeLogger },
  ],
})
export class AppModule {}

When using nestjs-pino, Nest log levels map to pino as: verbose → trace, debug → debug, log → info, warn → warn, error → error, fatal → fatal. If you use bootstrapLogLevel: 'verbose', set pino level: 'trace'.

// Verbose logging for a specific handler
@CommandHandler(CreateUserCommand)
@UsePipeline([LoggingBehavior, { requestResponseLogLevel: 'log' }])
export class CreateUserHandler { /* ... */ }

// Map specific exceptions to different log levels (e.g. log constraint violations as warnings)
@UsePipeline([LoggingBehavior, {
  mapLogLevel: new Map([
    [UniqueConstraintException, 'warn'],
    [NotFoundException, 'debug'],
  ])
}])

// Disable payload logging entirely, keep timing metrics
@UsePipeline([LoggingBehavior, { requestResponseLogLevel: 'none' }])

// Disable all logging for a handler
@UsePipeline([LoggingBehavior, { metricLogLevel: 'none', requestResponseLogLevel: 'none' }])

LoggingBehavior logs under the handler’s context, not its own. The handler name is passed with each log call, so a singleton logger is never mutated and concurrent handlers cannot overwrite one another’s context. With excludeRequestObj: false, excludeResponseObj: false:

Output example (on success):

[Nest] LOG   [CreateUserHandler] Request: {"username":"jane","email":"jane@example.com"}
[Nest] LOG   [CreateUserHandler] [019728a3-...] COMMAND CreateUserCommand → CreateUserHandler completed in 12.34ms
[Nest] DEBUG [CreateUserHandler] Response: {"id":"...","username":"jane","email":"jane@example.com"}

Output example (on error):

[Nest] ERROR [CreateUserHandler] [019728a3-...] COMMAND CreateUserCommand → CreateUserHandler failed after 2.10ms: Error: User already exists