Dynamic base URL middleware.

Used in place of Tesla’s builtin BaseUrl middleware because that freezes the URL at compile time and requires a clunky workaround to read it dynamically.

A dynamic BaseUrlFromConfig middleware is provided by Tesla (undocumented), but it’s quite rigid on where to find the configured URL, and since we control the requirements for this library it’s easier to just use this custom middleware, that is more specific to our use case.

Also, at the moment we’re making some strong assumptions on the format of the configured URL (no trailing slash), so that the implementation of this middleware can be simpler and faster. This will break if people configure URLs with a trailing slash.

This middleware does not require any option and automatically reads the base URL from the application configuration.

Example:

defmodule MyClient do
  use Tesla
  plug Routemaster.Middleware.BaseUrl
end