Elastic Log Handler for Debugr

This LogHandler adds logging to Elastic via SDK.

Installation

npm install --save @debugr/elastic

Usage

import { Logger, LogLevel } from '@debugr/core';
import { ElasticHandler } from '@debugr/elastic';

const globalContext = {
  applicationName: 'example',
};

const logger = new Logger(globalContext, [
  new ElasticHandler({
    index: 'example-app-logs',
  }),
]);

logger.setContextProperty('jobName', 'elasticTest');

logger.info('Application started.');
// should send a new entry to the `example-app-logs` index with the following content:
// {
//   level: 30,
//   message: 'Application started.',
//   ts: '2022-09-04T12:13:14Z',
//   context: {
//     applicationName: 'example',
//     jobName: 'elasticTest',
//   },
// }

Options

The ElasticHandler constructor accepts a required options object as the first argument. An instance of the Client class from the @elastic/elasticsearch SDK can be passed as the second argument; if it is not provided, the constructor will attempt to create it using the provided options object. So when calling the constructor with just a single argument, the options object is a union of the log handler options defined here and the Elastic Client options. See the @elastic/elasticsearch package documentations for the available Client options. The available options of the handler itself are as follows:

| Option | Type | Default | Description | |--------------------|--------------------------------------------|---------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | index | string, (entry: LogEntry) => string | (required) | The Elastic index to which entries will be sent. You can specify a callback to route each entry to a different index based e.g. on level. | | threshold | LogLevel | LogLevel.ALL | The lowest level of entries which will be logged. Any entries below this level will be ignored. | | bodyMapper | (entry: LogEntry) => Record<string, any> | (see description) | A callback transforming a LogEntry into the data object to be sent to Elastic. The default mapper will leave most of the entry data as-is, except the globalContext and taskContext objects which will be merged into a single context object, and the data object which will be serialized into JSON. | | errorCallback | (error: Error) => void | (see description) | A callback which will be called when sending an entry to Elastic fails. The default callback will simply log the error into the console. | | errorMsThreshold | number | (none) | Minimum time since last call to errorCallback before calling it again. |