HangfireIO/Hangfire · error · ArgumentNullException

pathTemplate

Error message

pathTemplate

What it means

The OWIN-specific AddBatchCommand overload (RouteCollectionExtensions.cs:72) throws ArgumentNullException when pathTemplate is null. The route collection needs a non-null path string to map the command dispatcher to a URL.

Source

Thrown at src/Hangfire.Core/Dashboard/RouteCollectionExtensions.cs:72

            [NotNull] string pathTemplate,
            [NotNull] Func<DashboardContext, bool> command)
        {
            if (routes == null) throw new ArgumentNullException(nameof(routes));
            if (pathTemplate == null) throw new ArgumentNullException(nameof(pathTemplate));
            if (command == null) throw new ArgumentNullException(nameof(command));

            routes.Add(pathTemplate, new CommandDispatcher(command));
        }

#if FEATURE_OWIN
        [Obsolete("Use the AddBatchCommand(RouteCollection, string, Func<DashboardContext, bool>) overload instead. Will be removed in 2.0.0.")]
        public static void AddBatchCommand(
            [NotNull] this RouteCollection routes, 
            [NotNull] string pathTemplate, 
            [NotNull] Action<RequestDispatcherContext, string> command)
        {
            if (routes == null) throw new ArgumentNullException(nameof(routes));
            if (pathTemplate == null) throw new ArgumentNullException(nameof(pathTemplate));
            if (command == null) throw new ArgumentNullException(nameof(command));

            routes.Add(pathTemplate, new BatchCommandDispatcher(command));
        }
#endif

        public static void AddBatchCommand(
            [NotNull] this RouteCollection routes,
            [NotNull] string pathTemplate,
            [NotNull] Action<DashboardContext, string> command)
        {
            if (routes == null) throw new ArgumentNullException(nameof(routes));
            if (pathTemplate == null) throw new ArgumentNullException(nameof(pathTemplate));
            if (command == null) throw new ArgumentNullException(nameof(command));

            routes.Add(pathTemplate, new BatchCommandDispatcher(command));
        }

View on GitHub (pinned to c236dd0f93)

Solutions

1. Provide a non-null path string (e.g. "/enqueue").
2. Validate configuration values before passing them as pathTemplate.

Example fix

// before
routes.AddBatchCommand(config.DeletePath, (ctx, id) => Delete(id));
// config.DeletePath is null

// after
routes.AddBatchCommand(config.DeletePath ?? "/delete", (ctx, id) => Delete(id));

if (string.IsNullOrEmpty(pathTemplate))
    throw new ArgumentException("pathTemplate is required.");
routes.AddBatchCommand(pathTemplate, handler);

When it happens

Trigger: Calling routes.AddBatchCommand(null, command) or routes.AddBatchCommand(someVariableThatIsNull, command) on the OWIN overload.

Common situations: Path template sourced from configuration that resolved to null; typo or missing constant; conditional path that evaluated to null.

Related errors

• routes
• command
• owinEnvironment
• routes
• app

AI-assisted analysis of HangfireIO/Hangfire@c236dd0f93 (2026-08-13). Data as JSON: /api/errors/1c50cd993bc369bb. Report an issue: GitHub.