init

lib/forum/application.ex

@@ -0,0 +1,72 @@
+# lib/forum/application.ex
+defmodule Forum.Application do
+  use Application
+
+  @impl true
+  def start(_type, _args) do
+    db_config = Application.fetch_env!(:forum, Forum.DB)
+    server_config = Application.fetch_env!(:forum, :server)
+
+    children =
+      [
+        {Postgrex, [name: Forum.DB] ++ db_config},
+
+        # Unique process names for forms, networks, public sites, and HTTP servers.
+        {Registry, keys: :unique, name: Forum.ProcessRegistry},
+
+        # WebSocket clients subscribe here for live forms.html updates.
+        {Registry, keys: :duplicate, name: Forum.FormsSubscriberRegistry},
+
+        Forum.LogStore,
+        Forum.Networks,
+        Forum.PublicSiteSupervisor,
+
+        # Parses forms.html and supervises one QuickBEAM runtime per
+        # <forms-> child element. Also serves Forum.Forms.html/0.
+        Forum.Forms,
+
+        # Re-parses forms.html whenever the file changes on disk.
+        Forum.Forms.Watcher,
+
+        # Main HTTP + WebSocket server.
+        http_server_child(:main, Forum.Router, server_config[:port])
+      ] ++ network_site_servers(server_config)
+
+    with {:ok, sup} <- Supervisor.start_link(children, strategy: :one_for_one, name: Forum.Supervisor) do
+      # DynamicSupervisor can't start children from its own init/1, so
+      # we kick off the initial parse + spawn here.
+      Forum.Forms.reload()
+      Forum.Networks.start_networks()
+      Forum.PublicSiteSupervisor.start_networks()
+      {:ok, sup}
+    end
+  end
+
+  defp network_site_servers(server_config) do
+    base_port = Keyword.get(server_config, :network_port_base, 4001)
+
+    Forum.Networks.network_slugs()
+    |> Enum.with_index()
+    |> Enum.map(fn {network, index} ->
+      http_server_child(
+        {:network, network},
+        {Forum.PublicSiteRouter, network: network},
+        base_port + index
+      )
+    end)
+  end
+
+  defp http_server_child(key, plug, port) do
+    Supervisor.child_spec(
+      {Bandit,
+       plug: plug,
+       port: port,
+       thousand_island_options: [
+         supervisor_options: [
+           name: {:via, Registry, {Forum.ProcessRegistry, {:http_server, key}}}
+         ]
+       ]},
+      id: {:http_server, key, port}
+    )
+  end
+end