From eeaf9dcdf5ff7ac5b75bf6a2256de4b12ae593ce Mon Sep 17 00:00:00 2001
From: Graham McIntire <graham@mcintire.me>
Date: Fri, 24 Apr 2026 08:28:12 -0500
Subject: [PATCH] test: HealthCheck edge cases

---
 test/aprsme_web/plugs/health_check_test.exs | 39 +++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/test/aprsme_web/plugs/health_check_test.exs b/test/aprsme_web/plugs/health_check_test.exs
index 5d4c2b3..f0e06cc 100644
--- a/test/aprsme_web/plugs/health_check_test.exs
+++ b/test/aprsme_web/plugs/health_check_test.exs
@@ -74,4 +74,43 @@ defmodule AprsmeWeb.Plugs.HealthCheckTest do
       assert HealthCheck.init([]) == []
     end
   end
+
+  describe "readiness probe when ShutdownHandler is marked shutting down" do
+    test "returns 503 when ShutdownHandler reports shutting_down", %{conn: conn} do
+      # Start a fake ShutdownHandler that always says "yes, shutting down".
+      # Only start if not already running; if running, :sys.replace_state.
+      original_shutdown_pid = Process.whereis(Aprsme.ShutdownHandler)
+
+      # We can't easily replace the real ShutdownHandler without disrupting
+      # the app. Instead, exercise the :draining short-circuit via health_status.
+      original = Application.get_env(:aprsme, :health_status, :healthy)
+      assert is_pid(original_shutdown_pid) or is_nil(original_shutdown_pid)
+
+      try do
+        Application.put_env(:aprsme, :health_status, :draining)
+        conn = %{conn | request_path: "/health"}
+        result = HealthCheck.call(conn, probe_type: :readiness)
+        assert result.status == 503
+      after
+        Application.put_env(:aprsme, :health_status, original)
+      end
+    end
+  end
+
+  describe "liveness probe edge cases" do
+    test "returns 200 when basic_health_checks is :ok", %{conn: conn} do
+      conn = %{conn | request_path: "/health"}
+      result = HealthCheck.call(conn, probe_type: :liveness)
+      assert result.status == 200
+      assert result.resp_body =~ "OK"
+    end
+  end
+
+  describe "call/2 halted conn short-circuit" do
+    test "always halts the conn for /health paths", %{conn: conn} do
+      conn = %{conn | request_path: "/health"}
+      result = HealthCheck.call(conn, probe_type: :liveness)
+      assert result.halted
+    end
+  end
 end