LogLayer

Transport Management ​

LogLayer provides methods to dynamically add, remove, and replace transports at runtime.

Parent-Child Isolation

Transport changes only affect the current logger instance. Child loggers created before the change will retain their original transports, and parent loggers are not affected when a child modifies its transports.

Potential Performance Impact

Modifying transports at runtime may have a performance impact if you are frequently creating / removing transports. It is recommended to re-use the same transport instance(s) where possible.

Adding Transports ​

addTransport(transports: LogLayerTransport | Array<LogLayerTransport>): ILogLayer

Adds one or more transports to the existing transports. If a transport with the same ID already exists, it will be replaced and its [Symbol.dispose]() method will be called if implemented.

typescript
// Add a single transport
logger.addTransport(new PinoTransport({
  logger: pino(),
  id: 'pino'
}))

// Add multiple transports at once
logger.addTransport([
  new ConsoleTransport({ logger: console, id: 'console' }),
  new PinoTransport({ logger: pino(), id: 'pino' })
])

// Replace an existing transport by using the same ID
logger.addTransport(new PinoTransport({
  logger: pino({ level: 'debug' }),
  id: 'pino'  // This will replace the existing 'pino' transport
}))

Removing Transports ​

removeTransport(id: string): boolean

Removes a transport by its ID. Returns true if the transport was found and removed, false otherwise.

If the transport implements the Disposable interface, its [Symbol.dispose]() method will be called automatically when removed.

typescript
const log = new LogLayer({
  transport: [
    new ConsoleTransport({ logger: console, id: 'console' }),
    new PinoTransport({ logger: pino(), id: 'pino' })
  ]
})

// Remove a specific transport
const wasRemoved = log.removeTransport('console')  // true

// Trying to remove a non-existent transport returns false
const notFound = log.removeTransport('nonexistent')  // false

Replacing All Transports ​

withFreshTransports(transports: LogLayerTransport | Array<LogLayerTransport>): ILogLayer

Replaces all existing transports with the provided transport(s). This is useful when you want to completely change the logging destinations. All existing transports will have their [Symbol.dispose]() method called if implemented.

typescript
// Replace with a single transport
logger.withFreshTransports(new PinoTransport({ logger: pino() }))

// Replace with multiple transports
logger.withFreshTransports([
  new ConsoleTransport({ logger: console }),
  new PinoTransport({ logger: pino() })
])

Obtaining the underlying logger instance ​

You can get the underlying logger for a transport if you've assigned an ID to it:

typescript
const log = new LogLayer({
  transport: new ConsoleTransport({
    logger: console,
    id: 'console'
  })
})

const consoleLogger = log.getLoggerInstance<typeof console>('console')
typescript
import { type P, pino } from "pino";
import { PinoTransport } from "@loglayer/transport-pino";

const log = new LogLayer({
  transport: new PinoTransport({
    logger: pino(),
    id: 'pino'
  })
})

const pinoLogger = log.getLoggerInstance<P.Pino>('pino')

INFO

Not all transports have a logger instance attached to them. In those cases, you will get a null result.

You can identify if a transport can return such an instance if it takes in a logger parameter in its constructor.