WIP: task to setup proxy endpoint

lib/beacon/igniter.ex

@@ -0,0 +1,36 @@
+defmodule Beacon.Igniter do
+  @moduledoc false
+
+  def select_router!(igniter, opts \\ []) do
+    label = Keyword.get(opts, :label)
+    raise_msg = Keyword.get(opts, :raise_msg, "No router found.")
+
+    case Igniter.Libs.Phoenix.select_router(igniter, label) do
+      {_igniter, nil} -> Mix.raise(raise_msg)
+      found -> found
+    end
+  end
+
+  def select_endpoint(igniter, router, label \\ "Which endpoint should be modified?") do
+    case Igniter.Libs.Phoenix.endpoints_for_router(igniter, router) do
+      {igniter, []} ->
+        {igniter, nil}
+
+      {igniter, [endpoint]} ->
+        {igniter, endpoint}
+
+      {igniter, endpoints} ->
+        {igniter, Igniter.Util.IO.select(label, endpoints, display: &inspect/1)}
+    end
+  end
+
+  def select_endpoint!(igniter, router, opts \\ []) do
+    label = Keyword.get(opts, :label)
+    raise_msg = Keyword.get(opts, :raise_msg, "No endpoint found.")
+
+    case select_endpoint(igniter, router, label) do
+      {_igniter, nil} -> Mix.raise(raise_msg)
+      found -> found
+    end
+  end
+end

lib/mix/tasks/beacon.gen.proxy_endpoint.ex

@@ -0,0 +1,113 @@
+defmodule Mix.Tasks.Beacon.Gen.ProxyEndpoint do
+  use Igniter.Mix.Task
+
+  @example "mix beacon.gen.proxy_endpoint"
+  @shortdoc "TODO"
+
+  @moduledoc """
+  #{@shortdoc}
+
+  ## Example
+
+  ```bash
+  #{@example}
+  ```
+  """
+
+  @doc false
+  def info(_argv, _composing_task) do
+    %Igniter.Mix.Task.Info{
+      group: :beacon,
+      example: @example,
+      schema: [key: :string, signing_salt: :string, same_site: :string],
+      defaults: [same_site: "Lax"]
+    }
+  end
+
+  @doc false
+  def igniter(igniter) do
+    otp_app = Igniter.Project.Application.app_name(igniter)
+    {igniter, router} = Beacon.Igniter.select_router!(igniter)
+    {igniter, fallback_endpoint} = Beacon.Igniter.select_endpoint(igniter, router, "Select a fallback endpoint (default app Endpoint):")
+    proxy_endpoint_module_name = Igniter.Libs.Phoenix.web_module_name(igniter, "ProxyEndpoint")
+    signing_salt = Keyword.get_lazy(igniter.args.options, :signing_salt, fn -> random_string(8) end)
+
+    igniter
+    |> create_proxy_endpoint_module(otp_app, fallback_endpoint, proxy_endpoint_module_name)
+    |> add_session_options_config(otp_app, signing_salt, igniter.args.options)
+    |> add_proxy_endpoint_config(otp_app, proxy_endpoint_module_name, signing_salt)
+    |> update_fallback_endpoint_signing_salt(otp_app, fallback_endpoint, signing_salt)
+    |> Igniter.add_notice("""
+    TODO
+    """)
+  end
+
+  defp create_proxy_endpoint_module(igniter, otp_app, fallback_endpoint, proxy_endpoint_module_name) do
+    if Igniter.Project.Module.module_exists(igniter, proxy_endpoint_module_name) do
+      Igniter.add_notice(igniter, """
+      Module #{inspect(proxy_endpoint_module_name)} already exists. Skipping.
+      """)
+    else
+      Igniter.Project.Module.create_module(igniter, proxy_endpoint_module_name, """
+        use Beacon.ProxyEndpoint,
+          otp_app: #{inspect(otp_app)},
+          session_options: Application.compile_env!(#{inspect(otp_app)}, :session_options),
+          fallback: #{inspect(fallback_endpoint)}
+      """)
+    end
+  end
+
+  def add_session_options_config(igniter, otp_app, signing_salt, options) do
+    key = Keyword.get_lazy(options, :key, fn -> "_#{otp_app}_key" end)
+    same_site = Keyword.get(options, :same_site, "Lax")
+
+    Igniter.Project.Config.configure(
+      igniter,
+      "config.exs",
+      otp_app,
+      [:session_options],
+      {:code,
+       Sourceror.parse_string!("""
+       [
+         store: :cookie,
+         key: "#{key}",
+         signing_salt: "#{signing_salt}",
+         same_site: "#{same_site}"
+       ]
+       """)}
+    )
+  end
+
+  def add_proxy_endpoint_config(igniter, otp_app, proxy_endpoint_module_name, signing_salt) do
+    igniter
+    |> Igniter.Project.Config.configure(
+      "config.exs",
+      otp_app,
+      [proxy_endpoint_module_name, :adapter],
+      {:code, Sourceror.parse_string!("Bandit.PhoenixAdapter")}
+    )
+    |> Igniter.Project.Config.configure(
+      "config.exs",
+      otp_app,
+      [proxy_endpoint_module_name, :live_view, :signing_salt],
+      signing_salt
+    )
+  end
+
+  defp update_fallback_endpoint_signing_salt(igniter, otp_app, fallback_endpoint, signing_salt) do
+    fallback_endpoint = String.to_atom("#{fallback_endpoint}")
+    dbg(fallback_endpoint)
+
+    Igniter.Project.Config.configure(
+      igniter,
+      "config.exs",
+      otp_app,
+      [fallback_endpoint, :live_view, :signing_salt],
+      signing_salt
+    )
+  end
+
+  # https://github.com/phoenixframework/phoenix/blob/c9b431f3a5d3bdc6a1d0ff3c29a229226e991195/installer/lib/phx_new/generator.ex#L451
+  defp random_string(length),
+    do: :crypto.strong_rand_bytes(length) |> Base.encode64() |> binary_part(0, length)
+end

lib/mix/tasks/beacon.gen.site.ex

@@ -44,8 +44,8 @@ defmodule Mix.Tasks.Beacon.Gen.Site do
     path = Keyword.fetch!(options, :path)
     validate_options!(site, path)
 
-    {igniter, router} = Igniter.Libs.Phoenix.select_router(igniter)
-    {igniter, [endpoint]} = Igniter.Libs.Phoenix.endpoints_for_router(igniter, router)
+    {igniter, router} = Beacon.Igniter.select_router!(igniter)
+    {igniter, endpoint} = Beacon.Igniter.select_endpoint!(igniter, router)
     repo = Igniter.Project.Module.module_name(igniter, "Repo")
 
     igniter

lib/mix/tasks/beacon.gen.tailwind_config.ex

@@ -35,8 +35,8 @@ defmodule Mix.Tasks.Beacon.Gen.TailwindConfig do
     site = Keyword.fetch!(options, :site) |> String.to_atom()
 
     app_name = Igniter.Project.Application.app_name(igniter)
-    {igniter, router} = Igniter.Libs.Phoenix.select_router(igniter)
-    {igniter, [endpoint]} = Igniter.Libs.Phoenix.endpoints_for_router(igniter, router)
+    {igniter, router} = Beacon.Igniter.select_router!(igniter)
+    {igniter, endpoint} = Beacon.Igniter.select_endpoint!(igniter, router)
 
     igniter
     |> create_tailwind_config()

lib/mix/tasks/beacon.install.ex

@@ -49,7 +49,7 @@ defmodule Mix.Tasks.Beacon.Install do
     argv = igniter.args.argv
     options = igniter.args.options
 
-    {igniter, router} = Igniter.Libs.Phoenix.select_router(igniter)
+    {igniter, router} = Beacon.Igniter.select_router!(igniter)
 
     igniter
     |> add_beacon_plugin_formatter()
@@ -64,7 +64,7 @@ defmodule Mix.Tasks.Beacon.Install do
   defp replace_error_html(igniter, router) do
     app_name = Igniter.Project.Application.app_name(igniter)
 
-    {igniter, [endpoint]} = Igniter.Libs.Phoenix.endpoints_for_router(igniter, router)
+    {igniter, endpoint} = Beacon.Igniter.select_endpoint!(igniter, router)
 
     Igniter.Project.Config.configure(
       igniter,