pino-http

The pino-http middleware attaches logger instances to the request and response objects, allowing you to perform manual logging within your route handlers.

• req.log: The logger instance used for request-related logs. If quietReqLogger is enabled, this will be the base logger.
• res.log: The logger instance used for response-related logs.
• req.allLogs / res.allLogs: Arrays containing the logger instances used during the lifecycle.

If quietReqLogger is enabled, req.log and res.log will point to the base logger instead of a child logger containing the full request object, which helps reduce log verbosity.

const pinoHttp = require('pino-http');
const http = require('http');

const server = http.createServer((req, res) => {
  pinoHttp()(req, res, () => {
    // Use the attached logger for manual logging
    req.log.info('Processing business logic...');
    res.end('Done');
  });
});

The pinoHttp([opts], [stream]) function accepts an options object to customize logging behavior. Key options include:

• logger: A parent pino instance used to create the child logger.
• genReqId: A function (req, res) => string | number to generate custom request IDs.
• useLevel: The logging level for responses (default: 'info').
• customLogLevel: A function (req, res, err) => string to dynamically determine the log level. Mutually exclusive with useLevel.
• autoLogging: Boolean or object to enable/disable automatic request/error logging. Defaults to true.
• customReceivedMessage, customSuccessMessage, customErrorMessage: Functions to customize the msg property for different request stages.
• customAttributeKeys: Object to rename default keys like req, res, err, and responseTime.
• customProps: Function or object to add additional properties to every log entry.
• quietReqLogger / quietResLogger: Boolean to reduce bindings on req.log and res.log to just the reqId.

const logger = require('pino-http')({
  logger: pino(),
  genReqId: function (req, res) {
    const existingID = req.id ?? req.headers["x-request-id"]
    if (existingID) return existingID
    const id = randomUUID()
    res.setHeader('X-Request-Id', id)
    return id
  },
  useLevel: 'info',
  customAttributeKeys: {
    req: 'request',
    res: 'response',
    err: 'error',
    responseTime: 'timeTaken'
  }
})

You can extend or replace the default serializers for req, res, and err.

• To extend standard serializers: Provide a function in the serializers option.
• To work with raw values: Set wrapSerializers: false. This passes the raw IncomingMessage or ServerResponse directly to your serializer instead of the pre-serialized object.

Note on Request Bodies: Logging request bodies is disabled by default for security. To enable it, you must manually assign the body to the request object within a custom req serializer.

// Example: Logging request body
const logger = require('pino-http')({
  serializers: {
    req(req) {
      req.body = req.raw.body;
      return req;
    },
  },
});

// Example: Using raw values (wrapSerializers: false)
const logger = require('pino-http')({
  wrapSerializers: false,
  serializers: {
    req (req) {
      return { message: req.foo };
    }
  }
})

The pinoLogger function (exported as pinoHttp) is the main entrypoint. It returns a middleware function compatible with Node.js HTTP servers. You can pass an options object and an optional stream to configure the logger.

Key configuration options include:

• customAttributeKeys: Object to rename default keys for req, res, err, reqId, and responseTime.
• customLogLevel: A function (req, res, err) => string to dynamically determine the log level.
• useLevel: The default log level (e.g., 'info') used if customLogLevel doesn't return a valid level.
• autoLogging: Boolean (defaults to true). If false, the middleware won't automatically log request completion.
• autoLogging.ignore: A function (req, res) => boolean to skip auto-logging for specific requests.
• genReqId: A function (req, res) => string to generate custom request IDs.
• customProps: A function (req, res) => object or an object to add custom properties to the logger child instance.

const pinoHttp = require('pino-http');
const http = require('http');

const server = http.createServer((req, res) => {
  // Use the middleware
  pinoHttp({ level: 'info' })(req, res, () => {
    res.end('Hello World');
  });
});

server.listen(3000);