Plug router compiling routes from file

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1

I’m trying to make something to help me when implementing BFFs (backend for frontends).
My idea is to have some route definitions on a file and read that file to create plug routes.

So far I have the following on my base plug router.

  [%{verb: :get, path: "dynamic/:name"}, %{verb: :post, path: "post"}] # Will be read from a file
  |> Enum.each(fn route ->
    Code.eval_quoted(
      {route.verb, [context: Routes, import: Plug.Router],
       [
         route.path,
         [
           do:
             {{:., [], [{:__aliases__, [alias: false], [:Handler]}, :call]}, [],
              [{:var!, [context: Routes, import: Kernel], [{:conn, [], Routes}]}, []]}
         ]
       ]},
      [],
      __ENV__
    )
  end)

It seems to be working, I can use all the plug routing goodiness and handle my proxying logic on my Handler plug.

But I have some issues.

  • I have no idea if Code.eval_quoted is the right aproach, I’m very new to macros and metaprogramming in Elixir
  • The routes are defined in compile time, so if I want to update the routes my options are recompiling/redeploying or maybe hot upgrades (I have no idea if its possible)
  • eval_quoted is safe? Does it have any performance implications?

Thanks in advance.

2 Likes
2

This is great question! I would like to know the same.