spm-agent-nodejs

This is the Node.js monitoring agent for Sematext Cloud.

The following information is collected and transmitted to Sematext:

OS Metrics (CPU / Mem)
Process Memory
EventLoop stats
Garbage Collector stats
Web server stats (requests, error rate, response times etc.) Working for all web servers frameworks that use Node.js http/https module including
- "connect" based frameworks
- Express.js,
- Sails.js
- Hapi.js
- Restify
- and others ...

The module is able to run in cluster mode (master/worker).

Status

Supported Node-Versions: Node >= 6.x.

Please check our blog for more information or contact us at npmjs@sematext.com.

Installation

How to Add Performance Monitoring to Node.js Applications


    npm install spm-agent-nodejs

Get a free account and create a Node.js API token at sematext.com/spm

Configuration

We use https://www.npmjs.com/package/rc for configuration. This means config parameters can be passed via several config locations command-line args or ENV variables. We recommend to use a file in current directory in INI or JSON format called ".spmagentrc". This file can be generated by calling a helper script:

    export MONITORING_TOKEN=YOUR-NODEJS-MONITORING-TOKEN
    export INFRA_TOKEN=YOUR-INFRA-MONITORING-TOKEN
    node ./node_modules/spm-agent-nodejs/bin/spmconfig.js

The command above generates following default configuration file (YAML format):

    # Directory for buffered metrics
    dbDir: ./spmdb

    # Application Token for SPM
    tokens:
      monitoring: YOUR-NODEJS-MONITORING-TOKEN
      infra: YOUR-INFRA-MONITORING-TOKEN

    logger
      # log file directory default is ./spmlogs
      dir: ./spmlogs
      # silent = true means no creation of log files
      silent: false
      # log level for output - debug, info, error, defaults to error to be quiet
      level: error

The only required setting is the Sematext App Token, this could be set via config file ".spmagentrc" or environment variable:

export spmagent_tokens__monitoring=YOUR-NODEJS-MONITORING-TOKEN

Please note the use of double "_" for nested properties

Configuration via Environment Variables

export MONITORING_TOKEN=YOUR-NODEJS-MONITORING-TOKEN
export INFRA_TOKEN=YOUR-INFRA-MONITORING-TOKEN
# default is SaaS at sematext.com, URL needs to be changed for on-prem to the local SPM receiver
export SPM_RECEIVER_URL=https://local-spm-server:8084/_bulk
export EVENTS_RECEIVER_URL=https://local-event-receiver/
export SPM_DB_DIR=/tmp
export SPM_LOG_DIRECTORY=./logs
export SPM_LOG_LEVEL=error
export SPM_LOG_TO_CONSOLE=true
export HTTPS_PROXY=http://my-local-proxy-server

Changing API endpoints for Sematext Cloud EU

export SPM_RECEIVER_URL=https://spm-receiver.eu.sematext.com/receiver/v1
export EVENTS_RECEIVER_URL=https://event-receiver.eu.sematext.com

Usage

Method 1: Preloading spm-agent-nodejs - no source code modifications requred

The command line option "-r" preloads node modules before the actual application is started. In this case the original source code needs no modification:

  node -r './spm-agent-nodejs' yourApp.js

Method 2: Add spm-agent-nodejs to your source code

Add this line at the begin of your source code / main script / app.js

# add spm-agent-nodejs to your project
npm i spm-agent-nodejs --save

require('spm-agent-nodejs')

With PM2

Use the absolute path to your .env file to enable PM2 monitoring.

// load env vars if you're using dotenv
require('dotenv').config({ path: '/absolute/path/to/your/project/.env' })
// start agent
require('spm-agent-nodejs')