allow embedded runtime by env

lib/livebook.ex

@@ -118,6 +118,14 @@ defmodule Livebook do
            Livebook.Config.default_runtime!("LIVEBOOK_DEFAULT_RUNTIME") ||
              Livebook.Runtime.ElixirStandalone.new()
 
+    config :livebook,
+           :runtime_modules,
+           [
+             Livebook.Runtime.ElixirStandalone,
+             Livebook.Runtime.MixStandalone,
+             Livebook.Runtime.Attached
+           ]
+
     if home = Livebook.Config.writable_dir!("LIVEBOOK_HOME") do
       config :livebook, :home, home
     end

lib/livebook/config.ex

@@ -26,6 +26,15 @@ defmodule Livebook.Config do
     Application.fetch_env!(:livebook, :default_runtime)
   end
 
+  @doc """
+  Returns if the runtime module is enabled.
+  """
+  @spec runtime_enabled?(module()) :: boolean()
+  def runtime_enabled?(runtime) do
+    runtime in Application.fetch_env!(:livebook, :runtime_modules) or
+      runtime == default_runtime().__struct__
+  end
+
   @doc """
   Returns the authentication mode.
   """

lib/livebook_web/live/session_live/attached_live.ex

@@ -5,6 +5,10 @@ defmodule LivebookWeb.SessionLive.AttachedLive do
 
   @impl true
   def mount(_params, %{"session" => session, "current_runtime" => current_runtime}, socket) do
+    unless Livebook.Config.runtime_enabled?(Livebook.Runtime.Attached) do
+      raise "runtime module not allowed"
+    end
+
     if connected?(socket) do
       Phoenix.PubSub.subscribe(Livebook.PubSub, "sessions:#{session.id}")
     end

lib/livebook_web/live/session_live/elixir_standalone_live.ex

@@ -5,6 +5,10 @@ defmodule LivebookWeb.SessionLive.ElixirStandaloneLive do
 
   @impl true
   def mount(_params, %{"session" => session, "current_runtime" => current_runtime}, socket) do
+    unless Livebook.Config.runtime_enabled?(Livebook.Runtime.ElixirStandalone) do
+      raise "runtime module not allowed"
+    end
+
     if connected?(socket) do
       Phoenix.PubSub.subscribe(Livebook.PubSub, "sessions:#{session.id}")
     end

lib/livebook_web/live/session_live/embedded_live.ex

@@ -5,6 +5,10 @@ defmodule LivebookWeb.SessionLive.EmbeddedLive do
 
   @impl true
   def mount(_params, %{"session" => session, "current_runtime" => current_runtime}, socket) do
+    unless Livebook.Config.runtime_enabled?(Livebook.Runtime.Embedded) do
+      raise "runtime module not allowed"
+    end
+
     if connected?(socket) do
       Phoenix.PubSub.subscribe(Livebook.PubSub, "sessions:#{session.id}")
     end

lib/livebook_web/live/session_live/mix_standalone_live.ex

@@ -7,6 +7,10 @@ defmodule LivebookWeb.SessionLive.MixStandaloneLive do
 
   @impl true
   def mount(_params, %{"session" => session, "current_runtime" => current_runtime}, socket) do
+    unless Livebook.Config.runtime_enabled?(Livebook.Runtime.MixStandalone) do
+      raise "runtime module not allowed"
+    end
+
     if connected?(socket) do
       Phoenix.PubSub.subscribe(Livebook.PubSub, "sessions:#{session.id}")
     end

lib/livebook_web/live/session_live/runtime_component.ex

@@ -30,34 +30,42 @@ defmodule LivebookWeb.SessionLive.RuntimeComponent do
       </h3>
       <div class="w-full flex-col space-y-5">
         <div class="flex space-x-4">
-          <.choice_button
-            active={@type == "elixir_standalone"}
-            phx-click="set_runtime_type"
-            phx-value-type="elixir_standalone"
-            phx-target={@myself}>
-            Elixir standalone
-          </.choice_button>
-          <.choice_button
-            active={@type == "mix_standalone"}
-            phx-click="set_runtime_type"
-            phx-value-type="mix_standalone"
-            phx-target={@myself}>
-            Mix standalone
-          </.choice_button>
-          <.choice_button
-            active={@type == "attached"}
-            phx-click="set_runtime_type"
-            phx-value-type="attached"
-            phx-target={@myself}>
-            Attached node
-          </.choice_button>
-          <.choice_button
-            active={@type == "embedded"}
-            phx-click="set_runtime_type"
-            phx-value-type="embedded"
-            phx-target={@myself}>
-            Embedded
-          </.choice_button>
+          <%= if Livebook.Config. runtime_enabled?(Livebook.Runtime.ElixirStandalone) do %>
+            <.choice_button
+              active={@type == "elixir_standalone"}
+              phx-click="set_runtime_type"
+              phx-value-type="elixir_standalone"
+              phx-target={@myself}>
+              Elixir standalone
+            </.choice_button>
+          <% end %>
+          <%= if Livebook.Config. runtime_enabled?(Livebook.Runtime.MixStandalone) do %>
+            <.choice_button
+              active={@type == "mix_standalone"}
+              phx-click="set_runtime_type"
+              phx-value-type="mix_standalone"
+              phx-target={@myself}>
+              Mix standalone
+            </.choice_button>
+          <% end %>
+          <%= if Livebook.Config. runtime_enabled?(Livebook.Runtime.Attached) do %>
+            <.choice_button
+              active={@type == "attached"}
+              phx-click="set_runtime_type"
+              phx-value-type="attached"
+              phx-target={@myself}>
+              Attached node
+            </.choice_button>
+          <% end %>
+          <%= if Livebook.Config. runtime_enabled?(Livebook.Runtime.Embedded) do %>
+            <.choice_button
+              active={@type == "embedded"}
+              phx-click="set_runtime_type"
+              phx-value-type="embedded"
+              phx-target={@myself}>
+              Embedded
+            </.choice_button>
+          <% end %>
         </div>
         <div>
           <%= live_render @socket, live_view_for_type(@type),

test/test_helper.exs

@@ -11,6 +11,13 @@ Livebook.Runtime.ErlDist.NodeManager.start(
 # and setting them explicitly
 Application.put_env(:livebook, :default_runtime, Livebook.Runtime.Embedded.new())
 
+Application.put_env(:livebook, :runtime_modules, [
+  Livebook.Runtime.ElixirStandalone,
+  Livebook.Runtime.MixStandalone,
+  Livebook.Runtime.Attached,
+  Livebook.Runtime.Embedded
+])
+
 defmodule Livebook.Runtime.Embedded.Dependencies do
   def entries() do
     [