Animated QR data transfer with Gomobile and Gopherjs · divan's blog

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TL;DR: a weekend project for transferring data via animated QR codes, written in Go. The Go code is reused for mobile apps using Gomobile, and in a web application for automating testing QR codes parameters, built with GopherJS and Vecty framework.I’ll share my experience building it, some code and benchmark results of using animated QR as a data transfer method.The problemOne day I was trying to find a viable solution for the following scenario:Imagine you’re in the crowded place and suddenly your messenger stop working because your authoritarian government blocked it. Maybe they just banned IP addresses of bootnodes for the messenger, or restricted access to some hosts via state-controlled DNS providers, or cut off yet another VPN or proxy service – it doesn’t actually relevant here. The question is – how to re-enable connectivity if at least one device has a working connection and willing to share connectivity information with others.Now, that’s rather a long introduction, bu…