Building a basic cache with SQLite

This website is a static website, built with a static site generator I wrote myself. When I’m working on the site locally, I want it to build quickly. The site is relatively small, modern computers are overflowing with power, so I don’t want to be waiting. Rendering all the HTML pages takes about 15 seconds – slow enough that I feel the delay every time. When I was using Jekyll, everything got much faster when I used the Jekyll cache. There’s a bunch of expensive computation that doesn’t need to be repeated every time I build the site – for example, converting a chunk of Markdown to HTML can be done once and cached forever. Since I’m no longer using Jekyll, I’ve replaced the Jekyll cache with a basic SQLite cache. I chose SQLite because it’s fast, familiar, and I can use it with the Python standard library. Every cache entry has three parts: a namespace, key, and value. The namespace groups all entries from a single operation, the key identifies an individual entry, and the value is…