Add a --dry-run flag to livebook deploy CLI (#3109)

Co-authored-by: Jonatan Kłosko <jonatanklosko@gmail.com>

Author: soundmonster

lib/livebook_cli/deploy.ex

@@ -17,6 +17,7 @@ defmodule LivebookCLI.Deploy do
       --org-token             Token from your Livebook Teams organization
       --teams-key             Teams key from your Teams workspace
       --deployment-group-id   The ID of the deployment group you want to deploy to
+      --dry-run               Perform a sanity check but do not actually deploy
 
     The --help option can be given to print this notice.
 
@@ -35,7 +36,8 @@ defmodule LivebookCLI.Deploy do
   @switches [
     org_token: :string,
     teams_key: :string,
-    deployment_group_id: :integer
+    deployment_group_id: :integer,
+    dry_run: :boolean
   ]
 
   @impl true
@@ -56,7 +58,8 @@ defmodule LivebookCLI.Deploy do
       paths: paths,
       session_token: opts[:org_token],
       teams_key: opts[:teams_key],
-      deployment_group_id: opts[:deployment_group_id]
+      deployment_group_id: opts[:deployment_group_id],
+      dry_run?: opts[:dry_run] || false
     }
   end
 
@@ -152,7 +155,8 @@ defmodule LivebookCLI.Deploy do
           |> Livebook.FileSystem.File.resolve("files/")
 
         with {:ok, content} <- File.read(path),
-             {:ok, app_deployment} <- prepare_app_deployment(path, content, files_dir) do
+             {:ok, app_deployment} <- prepare_app_deployment(path, content, files_dir),
+             :continue <- ensure_skip_on_dry_run(app_deployment, config.dry_run?) do
           case Livebook.Teams.deploy_app_from_cli(
                  team,
                  app_deployment,
@@ -212,6 +216,19 @@ defmodule LivebookCLI.Deploy do
     end
   end
 
+  defp ensure_skip_on_dry_run(app_deployment, dry_run?) do
+    if dry_run? do
+      message = """
+        * #{app_deployment.title} skipped due to --dry-run 
+      """
+
+      log_info(message)
+      :ok
+    else
+      :continue
+    end
+  end
+
   defp add_error(errors, key, message) do
     Map.update(errors, key, [message], &[message | &1])
   end

test/livebook_teams/cli/deploy_test.exs

@@ -380,7 +380,7 @@ defmodule LivebookCLI.Integration.DeployTest do
       deployment_group = TeamsRPC.create_deployment_group(node, org: org, url: @url)
       hub_id = team.id
 
-      # Notebook without app settings (deploymeny should fail)
+      # Notebook without app settings (deployment should fail)
       invalid_title = "Invalid App"
       invalid_slug = "invalid-#{Utils.random_short_id()}"
       invalid_app_path = Path.join(tmp_dir, "#{invalid_slug}.livemd")
@@ -481,9 +481,63 @@ defmodule LivebookCLI.Integration.DeployTest do
         end)
       end)
     end
+
+    test "successfully runs without deploying when dry run requested", %{
+      team: team,
+      node: node,
+      org: org,
+      tmp_dir: tmp_dir
+    } do
+      title = "Test CLI Deploy App"
+      slug = Utils.random_short_id()
+      app_path = Path.join(tmp_dir, "#{slug}.livemd")
+      {key, _} = TeamsRPC.create_org_token(node, org: org)
+      deployment_group = TeamsRPC.create_deployment_group(node, org: org, url: @url)
+      app_folder = TeamsRPC.create_app_folder(node, org: org)
+
+      hub_id = team.id
+      deployment_group_id = to_string(deployment_group.id)
+      app_folder_id = to_string(app_folder.id)
+
+      stamp_notebook(app_path, """
+      <!-- livebook:{"app_settings":{"access_type":"public","app_folder_id":"#{app_folder_id}","slug":"#{slug}"},"hub_id":"#{hub_id}"} -->
+
+      # #{title}
+
+      ## Test Section
+
+      ```elixir
+      IO.puts("Hello from CLI deployed app!")
+      ```
+      """)
+
+      output =
+        ExUnit.CaptureIO.capture_io(fn ->
+          assert deploy(
+                   key,
+                   team.teams_key,
+                   deployment_group.id,
+                   app_path,
+                   ["--dry-run"]
+                 ) == :ok
+        end)
+
+      assert output =~ "* Preparing to deploy notebook #{slug}.livemd"
+      assert output =~ "  * #{title} skipped due to --dry-run"
+
+      refute_receive {:app_deployment_started,
+                      %{
+                        title: ^title,
+                        slug: ^slug,
+                        deployment_group_id: ^deployment_group_id,
+                        app_folder_id: ^app_folder_id,
+                        hub_id: ^hub_id,
+                        deployed_by: "CLI"
+                      }}
+    end
   end
 
-  defp deploy(org_token, teams_key, deployment_group_id, path) do
+  defp deploy(org_token, teams_key, deployment_group_id, path, extra_flags \\ []) do
     paths =
       if is_list(path) do
         path
@@ -509,7 +563,7 @@ defmodule LivebookCLI.Integration.DeployTest do
         teams_key,
         "--deployment-group-id",
         deployment_group_id
-      ] ++ paths
+      ] ++ extra_flags ++ paths
     )
   end
 end