chore: helper script to bootstrap umbrella `mix.exs` files

fiatlux.exs

@@ -0,0 +1,136 @@
+#!/usr/bin/env elixir
+
+defmodule FiatLux do
+  def main(argv) do
+    {flags, [app_path]} = OptionParser.parse!(argv, strict: [force: :boolean])
+    force = Keyword.get(flags, :force, false)
+    ["apps", app_name] = Path.split(app_path)
+
+    {:ok, rebar_props} =
+      app_path
+      |> Path.join("rebar.config")
+      |> :file.consult()
+
+    {:ok, [{:application, app_name, app_props}]} =
+      [app_path, "src", app_name <> ".app.src"]
+      |> Path.join()
+      |> :file.consult()
+
+    app_deps =
+      app_props
+      |> Keyword.get(:applications, [])
+      |> Kernel.--([:kernel, :stdlib])
+
+    umbrella_deps =
+      rebar_props
+      |> Keyword.get(:deps, [])
+      # |> Enum.filter(fn x ->
+      #   match?({_, {:path, _}}, x)
+      # end)
+      |> Enum.map(fn
+        {app, {:path, _}} ->
+          # hack to format 2-tuple
+          {:__block__, [], [{app, in_umbrella: true}]}
+
+        {app, {:git, url, {:tag, tag}}} ->
+            slug =
+              url
+              |> to_string()
+              |> String.replace_prefix("https://github.com/", "")
+              |> String.replace_suffix(".git", "")
+          # hack to format 2-tuple
+          {:__block__, [], [{app, github: slug, tag: to_string(tag)}]}
+
+        {app, {:git_subdir, url, {:tag, tag}, subdir}} ->
+            slug =
+              url
+              |> to_string()
+              |> String.replace_prefix("https://github.com/", "")
+              |> String.replace_suffix(".git", "")
+          # hack to format 2-tuple
+          {:__block__, [], [{app, github: slug, tag: to_string(tag), sparse: to_string(subdir)}]}
+
+        {app, vsn} when is_list(vsn) ->
+          # hack to format 2-tuple
+          {:__block__, [], [{app, to_string(vsn)}]}
+      end)
+
+    app_mod = Keyword.get(app_props, :mod)
+
+    code_str =
+      mix_project(app_name, app_mod, umbrella_deps)
+      |> Code.quoted_to_algebra()
+      |> Inspect.Algebra.format(95)
+
+    IO.puts(code_str)
+
+    dest = Path.join([app_path, "mix.exs"])
+    if File.exists?(dest) && not force do
+      IO.puts("#{dest} already exists!")
+      exit(1)
+    else
+      File.write!(dest, [code_str, "\n"])
+      IO.puts("written #{dest}")
+    end
+  end
+
+  def mix_project(app_name, app_mod, umbrella_deps) do
+    application = if app_mod do
+      quote do
+        [
+          extra_applications: UMP.extra_applications(),
+          mod: unquote(app_mod)
+        ]
+      end
+    else
+      quote do
+        [
+          extra_applications: UMP.extra_applications()
+        ]
+      end
+    end
+    mod_name =
+      app_name
+      |> to_string()
+      |> String.replace_prefix("emqx_", "")
+      |> Macro.camelize()
+      |> then(& "Elixir.EMQX" <> &1 <> ".MixProject")
+      |> String.to_atom()
+    quote do
+      defmodule unquote(mod_name) do
+        use Mix.Project
+        alias EMQXUmbrella.MixProject, as: UMP
+
+        def project do
+          [
+            app: unquote(app_name),
+            version: "0.1.0",
+            build_path: "../../_build",
+            # config_path: "../../config/config.exs",
+            erlc_options: UMP.erlc_options(),
+            erlc_paths: UMP.erlc_paths(),
+            deps_path: "../../deps",
+            lockfile: "../../mix.lock",
+            elixir: "~> 1.14",
+            start_permanent: Mix.env() == :prod,
+            deps: deps()
+          ]
+        end
+
+        # Run "mix help compile.app" to learn about applications
+        def application do
+          unquote(application)
+        end
+
+        def deps() do
+          [
+            unquote_splicing(umbrella_deps)
+          ]
+        end
+      end
+    end
+  end
+end
+
+System.argv()
+|> FiatLux.main()