Problem How best to manage the state of interactive browser-based visualizations. Context Interactive web applications composed of data-driven visualizations typically take advantage of open source JavaScript libraries. Choosing the right visualization library is one of the developer’s first decisions, and an important but sometimes hidden element of this decision is how the library maintains interaction state. In the early days of the web it might be said that the DOM was the state, and many excellent visualization libraries start with this assumption....

Prelude and Caveat This post builds on another post that introduces RESTful APIs using Node-RED. If you haven’t read it already, please see that post. It should be repeated that there are other – perhaps better – ways besides a RESTful API for connecting a MIDI device to a web application. In a future post I will extend this MIDI example using web sockets, but please note that the central purpose of this discussion is not to demonstrate an ideal solution but rather to demonstrate the value of API prototyping using visual tools....

Problem When building new web application prototypes there is value in rapid redesign on both clients and servers. Can we make it easy for client programmers to tinker with server prototypes? Context While in many situations it is possible to create a mock server API for clients to consume, in some cases there is value in more realistic data sources. Examples include real-time collaboration and Internet-of-Things (IoT) scenarios. The situation can arise in small agile teams whose focus is primarily on web client applications, but who depend on evolving or establishing server-based resources and APIs....