node-statsd

A node.js client for Etsy's StatsD server and Datadog's DogStatsD server.

This client will let you fire stats at your StatsD server from a node.js application.

node-statsd Runs and is tested on Node 0.6+ on all *nix platforms and 0.8+ on all platforms including Windows.

Installation

$ npm install node-statsd

Usage

All initialization parameters are optional.

Parameters (specified as an options hash):

host: The host to send stats to default: localhost
port: The port to send stats to default: 8125
prefix: What to prefix each stat name with default: ''
suffix: What to suffix each stat name with default: ''
globalize: Expose this StatsD instance globally? default: false
cacheDns: Cache the initial dns lookup to host default: false
mock: Create a mock StatsD instance, sending no stats to the server? default: false
global_tags: Optional tags that will be added to every metric default: []

All StatsD methods other than event have the same API:

name: Stat name required
value: Stat value required except in increment/decrement where it defaults to 1/-1 respectively
sampleRate: Sends only a sample of data to StatsD default: 1
tags: The Array of tags to add to metrics default: []
callback: The callback to execute once the metric has been sent

If an array is specified as the name parameter each item in that array will be sent along with the specified value.

The event method has the following API:

title: Event title required
text: Event description default is title
options: Options for the event
- date_happened Assign a timestamp to the event default is now
- hostname Assign a hostname to the event.
- aggregation_key Assign an aggregation key to the event, to group it with some others.
- priority Can be ‘normal’ or ‘low’ default: normal
- source_type_name Assign a source type to the event.
- alert_type Can be ‘error’, ‘warning’, ‘info’ or ‘success’ default: info
tags: The Array of tags to add to metrics default: []
callback: The callback to execute once the metric has been sent

  var StatsD = require('node-statsd'),
      client = new StatsD();

  // Timing: sends a timing command with the specified milliseconds
  client.timing('response_time', 42);

  // Increment: Increments a stat by a value (default is 1)
  client.increment('my_counter');

  // Decrement: Decrements a stat by a value (default is -1)
  client.decrement('my_counter');

  // Histogram: send data for histogram stat
  client.histogram('my_histogram', 42);

  // Gauge: Gauge a stat by a specified amount
  client.gauge('my_gauge', 123.45);

  // Set: Counts unique occurrences of a stat (alias of unique)
  client.set('my_unique', 'foobar');
  client.unique('my_unique', 'foobarbaz');

  // Event: sends the titled event
  client.event('my_title', 'description');

  // Incrementing multiple items
  client.increment(['these', 'are', 'different', 'stats']);

  // Sampling, this will sample 25% of the time the StatsD Daemon will compensate for sampling
  client.increment('my_counter', 1, 0.25);

  // Tags, this will add user-defined tags to the data
  client.histogram('my_histogram', 42, ['foo', 'bar']);

  // Using the callback
  client.set(['foo', 'bar'], 42, function(error, bytes){
    //this only gets called once after all messages have been sent
    if(error){
      console.error('Oh noes! There was an error:', error);
    } else {
      console.log('Successfully sent', bytes, 'bytes');
    }
  });

  // Sampling, tags and callback are optional and could be used in any combination
  client.histogram('my_histogram', 42, 0.25); // 25% Sample Rate
  client.histogram('my_histogram', 42, ['tag']); // User-defined tag
  client.histogram('my_histogram', 42, next); // Callback
  client.histogram('my_histogram', 42, 0.25, ['tag']);
  client.histogram('my_histogram', 42, 0.25, next);
  client.histogram('my_histogram', 42, ['tag'], next);
  client.histogram('my_histogram', 42, 0.25, ['tag'], next);

DogStatsD-specific usage

Some of the functionality mentioned above is specific to DogStatsD and will not do anything if are using the regular statsd client. This includes:

global_tags parameter
tags parameter
histogram API
event API

Errors

In the event that there is a socket error, node-statsd will allow this error to bubble up. If you would like to catch the errors, just attach a listener to the socket property on the instance.

client.socket.on('error', function(error) {
  return console.error("Error in socket: ", error);
});

If you want to catch errors in sending a message then use the callback provided.

License

node-statsd is licensed under the MIT license.

bdeitte / node-statsd