Skip to content
Swizec Teller - a geek with a hatswizec.com

Making statsd talk directly to a browser

StatsD is "A network daemon that runs on the Node.js platform and listens for statistics, like counters and timers, sent over UDP and sends aggregates to one or more pluggable backend services"

I've previously mentioned StatsD in Your startup needs a dashboard over at Zemanta's fruitblog.

The idea behind StatsD is this:

  1. Stuff happens
  2. Send metrics of "stuff" to a central service (StatsD)
  3. StatsD acts as a buffer, forwards aggregated metrics every X seconds

Your architecture now has a central service that collects all of your metrics, then pushes them to appropriate software, that doesn't need to handle too much traffic and is guaranteed data will come from a single source in a sanitized format.

A software architect's dream

Straight from the browser?

Collecting data into StatsD works wonderfully. It's fast, reliable, extremely robust and you can give it just about any data you can think of.

Unless your client is a browser.

See, StatsD only accepts UDP packets and browsers don't let you send UDP packets. There's a valid excuse for this - it doesn't matter if some packets are lost, as long as whatever you're measuring isn't slowed down by the measuring.

To solve this I created a simple proxy in node.js. It accepts normal HTTP requests and pushes data onward to StatsD. The simplicity, I hope, ensures speed.

The API is a simple tracking pixel:

<img src="http://<address>?t=<type>&v=<value>&b=<bucket>" />

Where type is one of c (counter), t (timer), g (gauge). As per StatsD naming convention. And bucket is simply the name of your metric.

The source is on github. Feel free to use it.

Straight to the browser

Ok, so now we can collect data from the browser ... but I want to send it directly to a browser as well. None of that Graphite stuff - I want to use some other fancy graphs and visualisations. Just because.

To solve this problem I implemented a socket.io backend for StatsD. It, also, can be found on github -> https://github.com/etsy/statsd/pull/102

Hope the pull request gets merged soon, or at all for that matter. I really think this is a useful addition to StatsD because it means you can use whatever client-side javascript to do visualisations. In near real-time and all that.

The data is sent over in a simple format:

{perSecond: {bucket1: 0.2,
bucket2: 0.1
},
counts: {bucket1: 2,
bucket2: 1
},
timers: {timer1: {upper: 2.4,
lower: 1.2,
count: 10}
},
gauges: {gauge1: 10
},
statsd: {numStats: 6},
timestamp: <unix timestamp="">}
</unix>

The goal?

If all goes well, I will soon be able to use cubism.js to draw a pretty timeseries of the traffic on this blog. And hey, who knows what else I can think of to add to a personal dashboard of my life ... I now have the basic framework. Time to start using it.

Cubism.js makes shiny timeseries







Enhanced by Zemanta

Did you enjoy this article?

Published on June 15th, 2012 in Uncategorized

Learned something new?
Want to become a high value JavaScript expert?

Here's how it works 👇

Leave your email and I'll send you an Interactive Modern JavaScript Cheatsheet 📖right away. After that you'll get thoughtfully written emails every week about React, JavaScript, and your career. Lessons learned over my 20 years in the industry working with companies ranging from tiny startups to Fortune5 behemoths.

Start with an interactive cheatsheet 📖

Then get thoughtful letters 💌 on mindsets, tactics, and technical skills for your career.

"Man, love your simple writing! Yours is the only email I open from marketers and only blog that I give a fuck to read & scroll till the end. And wow always take away lessons with me. Inspiring! And very relatable. 👌"

~ Ashish Kumar

Join over 10,000 engineers just like you already improving their careers with my letters, workshops, courses, and talks. ✌️

Have a burning question that you think I can answer? I don't have all of the answers, but I have some! Hit me up on twitter or book a 30min ama for in-depth help.

Ready to Stop copy pasting D3 examples and create data visualizations of your own?  Learn how to build scalable dataviz components your whole team can understand with React for Data Visualization

Curious about Serverless and the modern backend? Check out Serverless Handbook, modern backend for the frontend engineer.

Ready to learn how it all fits together and build a modern webapp from scratch? Learn how to launch a webapp and make your first 💰 on the side with ServerlessReact.Dev

Want to brush up on your modern JavaScript syntax? Check out my interactive cheatsheet: es6cheatsheet.com

By the way, just in case no one has told you it yet today: I love and appreciate you for who you are ❤️