nixos/octoprint: add tests for reachability over IPv6

nixos/tests/octoprint.nix

@@ -50,11 +50,18 @@ in
     # used to fail early, in case octoprint first starts and then crashes
     with octoprint_running: # type: ignore[union-attr]
         with subtest("Check for web interface"):
-            machine.wait_until_succeeds("curl -s localhost:5000")
+            machine.wait_until_succeeds("curl -s -4 localhost:5000")
+            machine.wait_until_succeeds("curl -s -6 localhost:5000")
 
-        with subtest("Check API"):
-            version = json.loads(machine.succeed(curl_cmd + "localhost:5000/api/version"))
-            server = json.loads(machine.succeed(curl_cmd + "localhost:5000/api/server"))
+        with subtest("Check API IPv4"):
+            version = json.loads(machine.succeed(curl_cmd + "-4 localhost:5000/api/version"))
+            server = json.loads(machine.succeed(curl_cmd + "-4 localhost:5000/api/server"))
+            assert version["server"] == str("${pkgs.octoprint.version}")
+            assert server["safemode"] == None
+
+        with subtest("Check API IPv6"):
+            version = json.loads(machine.succeed(curl_cmd + "-6 localhost:5000/api/version"))
+            server = json.loads(machine.succeed(curl_cmd + "-6 localhost:5000/api/server"))
             assert version["server"] == str("${pkgs.octoprint.version}")
             assert server["safemode"] == None
   '';