fix: harden check_suite staging-completed path to no-op if batch is missing

Author: bryangingechen

lib/web/controllers/webhook_controller.ex

@@ -267,13 +267,21 @@ defmodule BorsNG.WebhookController do
 
     case {action, branch} do
       {"completed", ^staging_branch} ->
-        Batch
-        |> Repo.get_by!(commit: sha, project_id: project.id)
-        |> Batch.changeset(%{last_polled: 0})
-        |> Repo.update!()
-
-        batcher = Batcher.Registry.get(project.id)
-        Batcher.poll(batcher)
+        case Repo.get_by(Batch, commit: sha, project_id: project.id) do
+          nil ->
+            Logger.debug([
+              "Ignoring check_suite completed for unknown staging commit: ",
+              sha
+            ])
+
+          batch ->
+            batch
+            |> Batch.changeset(%{last_polled: 0})
+            |> Repo.update!()
+
+            batcher = Batcher.Registry.get(project.id)
+            Batcher.poll(batcher)
+        end
 
       {"completed", ^trying_branch} ->
         attemptor = Attemptor.Registry.get(project.id)

test/controllers/webhook_controller_test.exs

@@ -556,6 +556,24 @@ defmodule BorsNG.WebhookControllerTest do
     assert Enum.any?(comments, &String.contains?(&1, "now in draft mode"))
   end
 
+  test "ignore check_suite completed for unknown staging commit", %{conn: conn} do
+    body_params = %{
+      "repository" => %{"id" => 13},
+      "action" => "completed",
+      "check_suite" => %{
+        "head_branch" => "staging",
+        "head_sha" => "missing_batch_commit"
+      }
+    }
+
+    conn =
+      conn
+      |> put_req_header("x-github-event", "check_suite")
+      |> post(webhook_path(conn, :webhook, "github"), body_params)
+
+    assert conn.status == 200
+  end
+
   def wait_until_other_branch_is_removed do
     branches =
       GitHub.ServerMock.get_state()