alligator-metrics

alligator-metrics is a Ganglia metrics reporter. #Quick Start

vi config/metrics.js

npm start

#Configuration Config files for metrics in config/metrics ##General

• Edit config/metrics.js
• Add Ganglia masters to array

return {
  hosts:[{
    host:'localhost', 
    port:8649 // gmond port
  }]
};

Redis Metrics

• Edit config/metrics/redis.js

 return {
      redis:{
        enabled:true, // enable/disable
        host:'localhost',
        port: 6379,
        database:0
      }
    };

Elasticsearch Metrics

• Edit config/metrics/elasticsearch.js

return { 
  elasticsearch:{
    enabled:true, // enable/disable
    host:"http://localhost:9200",
    log:['error']
  }
};

Creating a Metric

You can create you own Metric by placing them in a ./metrics/ folder create a yourMetric.js file. Here's an example of a simple metric which will report to ganglia the number of cpus:

var os = require('os');
exports.cpus={
  title:'NodeJS CPUs Count',
  name: 'node_cpu_num',
  group: 'cpu',
  units: 'CPUs',
  slope: 'zero',
  type: 'uint16',
  description:'Number of CPUs',
  interval:1200,
  tmax:10,
  dmax:60,
  run:function(api,metric,send){
    metric.value=os.cpus().length;
    send(metric);
  }
};

#Metric Options

title:'NodeJS CPUs Count',
name: 'node_cpu_num',
group: 'cpu',
units: 'CPUs',  // unit of your metric
slope: 'zero',  // zero | positive | negative | both | unspecified
type: 'uint16', // string | uint | uint8 | uint16 | uint32 | int8 | int16 | int32 | float | double
description:'Number of CPUs',
interval:1200,  // Periodic reporting interval in milliseconds
tmax:10,
dmax:60

#Plugins

Creating a Plugin

• Create a project with the following structure:

/
  initializers/
  metrics/
  scripts/
  config/
  package.json

• Write an metric file in metrics/ folder for example:

  See the Creating a Metric section

• Write an config file for the metric to config/ folder for example config/metrics/cpu.js:

exports.default = {
  metrics: function(api){
    return { 
      'node_cpu_num':{
        enabled:true
      }
    };
  }
}

• Write an config install script to scripts/postinstall.js file for example:

#!/usr/bin/env node

var fs = require('fs');
var path = require('path');

var localConfig   = path.normalize(__dirname + '/../config/cpu.js');
var configPath = path.normalize(process.cwd() + '/../../config/metrics');
var config = path.normalize(process.cwd() + '/../../config/metrics/cpu.js');

if(!fs.existsSync(config)){
  console.log("coppying " + localConfig + " to " + config)
  try{ fs.mkdirSync(configPath); }catch(e){ }
  fs.createReadStream(localConfig).pipe(fs.createWriteStream(config));
}

• Add to package.json the install script:

"scripts": {
  "postinstall": "scripts/postinstall.js"
}

Including a Plugin

• Add to package.json your plugin:

  "dependencies": {
    "am-your-plugin":"1.0.0"
  }

• Add to config/api.js your plugin:

metrics:[ // this is a list of metric plugin names
  'am-your-plugin'
],

More Info