Architecture

Emanote is a Haskell program that, at its essense, transforms a bunch of “source files” (Markdown, static files, etc.) into a “target website”. It does that in a reactive manner such that as the source files change the resultant website updates in real-time (thanks to Ema’s hot-reload via websocket).

Emanote’s high-level architecture is as follows,

  • Emanote.Source: manages source files and communicates them to Emanote.Model.
    • The key concept here is the notion of “union mount”, implemented by Emanote.Source.Mount, which will eventually be made its own Haskell library.
  • Emanote.Model: Haskell types & machinary to represent the source files in memory, as well as a way to efficiently index and query into them.
    • The individual modules in this package should be imported separately to use the specific model types.
  • Emanote.Route: Route types
    • Emanote.Route.ModelRoute: Haskell route types to point to somewhere in Emanote.Model (eg: route to a .md file, or a route to a .jpeg file)
    • Emanote.Route.SiteRoute: Haskell route types pointing to somewhere in the generated site.
  • Emanote.View: Rendering code (HTML, templates, site routes)
  • Emanote.Pandoc: Everything to do with light-weight markup processing
    • Emanote.Pandoc.Markdown: Markdown-specific parsers and syntax.
    • Emanote.Pandoc.Renderer: Emanote-specific transformation of Pandoc AST, via Heist custom splicing.

Ema acts as the framework orchestrating two things at the same time:

  • Emanote.Source.emanate which is responsible for keeping the in-memory Model in sync with what’s on disk
  • Emanote.View.render which, whilst querying the Model, is responsible for producing the final HTML for every SiteRoute in the target website.

In addition, we have the following non-source files in the Git repository that are vital to Emanote’s functionality:

  • ./default: The primary and first “layer” used, which provides the default HTML templates (we use Heist), index.md and a favicon. Users can override these by creating an equivalent file (same path) in their own layer.
Links to this page
#emanote/dev