@tree-house/logger NPM

Tree House Logger

Custom NodeJS error classes and definitions with an error parser utility function.

Installation

Install via npm

npm install @tree-house/logger

or via yarn

yarn add @tree-house/logger

Usage

Setup

Service name & version (required for GCP Error Reporting) are determined by:

Environment variables npm_package_name and npm_package_version.
The options passed into the setup function.

The options passed into the setup function will override the values provided by the environment variables (if they were populated to begin with).

To use the setup function to populate name & version of your service, add the following to your startup code before using NSLogger:

import { setup } from '@tree-house/logger';

// NOTE: Name & version should ideally be grabbed from `package.json`
setup({ name: 'my-service', version: '1.2.3' })

Namespaces

You can use this logger with or without namespaces - namespaces help during debugging & are logged to stdout:

import { NSLogger, logger } from '@tree-house/logger';

NSLogger('my-namespace').info('tree house logger');
logger.info('tree house logger');

Debug

You can enable/disable all/some debug logs based on LOG_LEVEL and DEBUG environment variables. If you set LOG_LEVEL to debug (the default), you can use the DEBUG environment variable to enable these based on comma-delimited names.

To skip a specific namespace: DEBUG=*,-not_this To log a specific namespace: DEBUG=this:* To log multiple namespaces: DEBUG=this:*,that:*

Errors

LOG_FORMAT = simple

When LOG_FORMAT environment variable is not set, it defaults to simple. When using simple log format, log messages are outputted on one line, while parameters are outputted on the subsequent lines. This is ideal for a development environment.

LOG_FORMAT = json

When LOG_FORMAT environment variable is set to json, logs are in JSON format. Error log entries are following GCP Error Reporting format. To use it, you must pass an error object while calling .error. You can also provide httpRequest if you are logging an HTTP error:

import { NSLogger } from '@tree-house/logger';

NSlogger('my-namespace').error(
  'tree house logger',
  new Error('Something went wrong'),
  {
    httpRequest: { responseStatusCode: 404, url: 'https://google.com', method: 'GET' },
  },
)