DefaultValuePipe

DefaultValuePipe is a built-in NestJS pipe that provides a default value when a parameter is null or undefined. It is used before Parse* pipes to handle missing optional parameters:

@Get()
async findAll(
  @Query('activeOnly', new DefaultValuePipe(false), ParseBoolPipe) activeOnly: boolean,
  @Query('page', new DefaultValuePipe(0), ParseIntPipe) page: number,
) {
  // activeOnly defaults to false, page defaults to 0
}

Without DefaultValuePipe, Parse* pipes throw an exception on null/undefined values.