StatsD

This is a fork of Etsy's StatsD.

A network daemon that runs on the Node.js platform and listens for statistics, like counters and timers, sent over UDP (TCP coming soon!) and sends aggregates to one or more pluggable backend services (e.g., Graphite

Etsy blogged about how it works and why they created it.

Inspiration

StatsD was inspired (heavily) by the project (of the same name) at Flickr. Here's a post where Cal Henderson described it in depth: Counting and timing Cal re-released the code: Perl StatsD

Key Concepts

• buckets Each stat is in its own "bucket". They are not predefined anywhere. Buckets can be named anything that will translate to Graphite (periods make folders, etc)

• values Each stat will have a value. How it is interpreted depends on modifiers. In general values should be integer.

• flush After the flush interval timeout (defined by config.flushInterval, default 10 seconds), stats are aggregated and sent to an upstream backend service.

Installation and Configuration

• Install node.js
• Clone the project
• Create a config file that conforms to the schema described in schema/config.json. Example config can be seen in config.json
• Start the Daemon:
  node stats.js /path/to/config.json

Usage

The basic line protocol expects metrics to be sent in the format:

<metricname>:<value>|<type>[|@<rate>]

So the simplest way to send in metrics from your command line if you have StatsD running with the default UDP server on localhost would be:

echo "foo:1|c" | nc -u -w0 127.0.0.1 8125

More Specific Topics

• Metric Types
• Graphite Integration
• Supported Servers
• Supported Backends
• Server Interface
• Backend Interface

Debugging

The only way to debug StatsD is through logs.

You can set different log levels as required through config file.

Tests

This project uses Mocha as its test framework. Please add tests under test/ for any new features or bug fixes encountered. Testing a live server can be tricky, attempts were made to eliminate race conditions but it may be possible to encounter a stuck state.

Tests can be executed with npm test.