log4js-node/docs/logstashHTTP.md

logstash Appender (HTTP)

The logstash appenders send NDJSON formatted log events to logstash receivers. This appender uses HTTP to send the events (there is another logstash appender that uses UDP). You will need to include axios in your dependencies to use this appender.

Configuration

• type - logstashHTTP
• url - string - logFaces receiver servlet URL
• application - string (optional) - used to identify your application's logs
• logChannel - string (optional) - also used to identify your application's logs [but in a more specific way]
• logType - string (optional) - used for the type field in the logstash data
• timeout - integer (optional, defaults to 5000ms) - the timeout for the HTTP request.

This appender will also pick up Logger context values from the events, and add them as p_ values in the logFaces event. See the example below for more details.

Example (default config)

log4js.configure({
  appenders: {
    logstash: { type: 'logstashHTTP', url: 'http://localhost:9200/_bulk', application: 'logstash-log4js', logType: 'application', logChannel: 'node' }
  },
  categories: {
    default: { appenders: [ 'logstash' ], level: 'info' }
  }
});

const logger = log4js.getLogger();
logger.addContext('requestId', '123');
logger.info('some interesting log message');
logger.error('something has gone wrong');

This example will result in two log events being sent to your localhost:9200. Both events will have a context.requestId property with a value of 123.