From bfd47fd166bd2d213a917bac3317bf50bf08213a Mon Sep 17 00:00:00 2001
From: ByeongUk Choi <cbw0916@gmail.com>
Date: Fri, 15 Apr 2022 20:46:26 +0900
Subject: [PATCH] Add app service settings (#1116)

---
 README.md                              | 12 ++++++++---
 config/config.exs                      |  2 ++
 lib/livebook.ex                        |  8 +++++++
 lib/livebook/config.ex                 | 30 ++++++++++++++++++++++++++
 lib/livebook_web/live/settings_live.ex | 12 +++++++++++
 5 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index c4b782418..75d9818df 100644
--- a/README.md
+++ b/README.md
@@ -145,6 +145,12 @@ Livebook if said token is supplied as part of the URL.
 
 The following environment variables configure Livebook:
 
+  * LIVEBOOK_APP_SERVICE_NAME - sets the application name used by the cloud
+    provider to aid debugging.
+
+  * LIVEBOOK_APP_SERVICE_URL - sets the application url to manage this
+    Livebook instance within the cloud provider platform.
+
   * LIVEBOOK_COOKIE - sets the cookie for running Livebook in a cluster.
     Defaults to a random string that is generated on boot.
 
@@ -157,6 +163,9 @@ The following environment variables configure Livebook:
     "attached:NODE:COOKIE" (Attached node) or "embedded" (Embedded).
     Defaults to "standalone".
 
+  * LIVEBOOK_FORCE_SSL_HOST - sets a host to redirect to if the request is not over HTTP.
+    Note it does not apply when accessing Livebook via localhost. Defaults to nil.
+
   * LIVEBOOK_HOME - sets the home path for the Livebook instance. This is the
     default path used on file selection screens and others. Defaults to the
     user's operating system home.
@@ -187,9 +196,6 @@ The following environment variables configure Livebook:
     Enabled by default unless `LIVEBOOK_PASSWORD` is set. Set it to "false" to
     disable it.
 
-  * LIVEBOOK_FORCE_SSL_HOST - set a host to redirect to if the request is not over HTTP.
-    Note it does not apply when accessing Livebook via localhost. Defaults to nil.
-
 <!-- Environment variables -->
 
 If running Livebook as a Docker image or an Elixir release, [the environment
diff --git a/config/config.exs b/config/config.exs
index a0cf0b4a4..ded1955cc 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -20,6 +20,8 @@ config :mime, :types, %{
 }
 
 config :livebook,
+  app_service_name: nil,
+  app_service_url: nil,
   authentication_mode: :token,
   explore_notebooks: [],
   plugs: [],
diff --git a/lib/livebook.ex b/lib/livebook.ex
index d370255f1..236449d99 100644
--- a/lib/livebook.ex
+++ b/lib/livebook.ex
@@ -147,6 +147,14 @@ defmodule Livebook do
            Livebook.Config.cookie!("LIVEBOOK_COOKIE") ||
              Livebook.Config.cookie!("RELEASE_COOKIE") ||
              Livebook.Utils.random_cookie()
+
+    if app_service_name = Livebook.Config.app_service_name!("LIVEBOOK_APP_SERVICE_NAME") do
+      config :livebook, :app_service_name, app_service_name
+
+      config :livebook,
+             :app_service_url,
+             Livebook.Config.app_service_url!("LIVEBOOK_APP_SERVICE_URL")
+    end
   end
 
   @doc """
diff --git a/lib/livebook/config.ex b/lib/livebook/config.ex
index 15e802f18..49af96354 100644
--- a/lib/livebook/config.ex
+++ b/lib/livebook/config.ex
@@ -106,6 +106,22 @@ defmodule Livebook.Config do
     Application.fetch_env!(:livebook, :shutdown_enabled)
   end
 
+  @doc """
+  Returns the application service name.
+  """
+  @spec app_service_name() :: String.t() | nil
+  def app_service_name() do
+    Application.fetch_env!(:livebook, :app_service_name)
+  end
+
+  @doc """
+  Returns the application service url.
+  """
+  @spec app_service_url() :: String.t() | nil
+  def app_service_url() do
+    Application.fetch_env!(:livebook, :app_service_url)
+  end
+
   ## Parsing
 
   @doc """
@@ -224,6 +240,20 @@ defmodule Livebook.Config do
     System.get_env(env)
   end
 
+  @doc """
+  Parses application service name from env.
+  """
+  def app_service_name!(env) do
+    System.get_env(env)
+  end
+
+  @doc """
+  Parses application service url from env.
+  """
+  def app_service_url!(env) do
+    System.get_env(env)
+  end
+
   @doc """
   Parses and validates default runtime from env.
   """
diff --git a/lib/livebook_web/live/settings_live.ex b/lib/livebook_web/live/settings_live.ex
index 02e7d3abd..43970ad27 100644
--- a/lib/livebook_web/live/settings_live.ex
+++ b/lib/livebook_web/live/settings_live.ex
@@ -50,6 +50,18 @@ defmodule LivebookWeb.SettingsLive do
             </h1>
             <div class="flex items-center justify-between border border-gray-200 rounded-lg p-4">
               <div class="flex items-center space-x-12">
+                <%= if app_name = Livebook.Config.app_service_name() do %>
+                  <div class="flex flex-col space-y-1">
+                    <span class="text-sm text-gray-500">Application</span>
+                    <span class="text-gray-800 text-sm font-semibold">
+                      <%= if app_url = Livebook.Config.app_service_url() do %>
+                        <a href={app_url} target="_blank"><%= app_name %></a>
+                      <% else %>
+                        <%= app_name %>
+                      <% end %>
+                    </span>
+                  </div>
+                <% end %>
                 <.labeled_text label="Livebook" text={"v#{Application.spec(:livebook, :vsn)}"} />
                 <.labeled_text label="Elixir" text={"v#{System.version()}"} />
               </div>