Capturing A/V Multimedia Streams From the Browser

Background I’ve recently been working on finishing up an application to help gather presentation feedback when demo’ing a talk for the first time in front of a live audience. The app will play back a video stream and overlay the audiences comments on top of the video in real time. However I haven’t open sourced it yet because there was a dependency on launching an external video application to do the recording, and have the user upload that to the server. [Read More]

Distributed MySQL Sleuthing on the Wire

Intro Oftentimes you need to know what MySQL is doing right now and furthermore if you are handling heavy traffic you probably have multiple instances of it running across many nodes. I’m going to start by showing how to take a tcpdump capture on one node, a few ways to analyze that, and then go into how to take a distributed capture across many nodes for aggregate analysis. Taking the Capture The first thing you need to do is to take a capture of the interesting packets. [Read More]

Node.js, Websockets, and the Twitter Gardenhose

Introduction In this article I’m going to demonstrate how to use the Twitter Streaming API to send a stream of status updates for real time display in a web browser using Web Sockets. We’ll implement a backend server module that streams the events over a web socket using the node.websocket.js framework, which provides a simple realtime HTTP server that implements the web socket protocol. Node.websocket.js is built on top of Node. [Read More]