What causes "mux: route doesn't have methods" in gorilla/mux?

Treat the error as 'route accepts all methods' and default to a wildcard.

mux: route doesn't have methods

Error message

mux: route doesn't have methods

What it means

Returned by Route.GetMethods (route.go:767-776) when iterating the route's matchers and none is a methodMatcher, i.e. .Methods(...) was never called on the route (it accepts every method).

Source

Thrown at route.go:776

		queries = append(queries, query.template)
	}
	return queries, nil
}

// GetMethods returns the methods the route matches against
// This is useful for building simple REST API documentation and for instrumentation
// against third-party services.
// An error will be returned if route does not have methods.
func (r *Route) GetMethods() ([]string, error) {
	if r.err != nil {
		return nil, r.err
	}
	for _, m := range r.matchers {
		if methods, ok := m.(methodMatcher); ok {
			return []string(methods), nil
		}
	}
	return nil, errors.New("mux: route doesn't have methods")
}

// GetHostTemplate returns the template used to build the
// route match.
// This is useful for building simple REST API documentation and for instrumentation
// against third-party services.
// An error will be returned if the route does not define a host.
func (r *Route) GetHostTemplate() (string, error) {
	if r.err != nil {
		return "", r.err
	}
	if r.regexp.host == nil {
		return "", errors.New("mux: route doesn't have a host")
	}
	return r.regexp.host.template, nil
}

// GetVarNames returns the names of all variables added by regexp matchers

View on GitHub (pinned to db9d1d0073)

Solutions

Treat the error as 'route accepts all methods' and default to a wildcard.
Call .Methods(...) on routes that should declare verbs.
Default to ["*"] or []string{} in docs when it errors.

Example fix

// before
ms, err := route.GetMethods()

// after
ms, err := route.GetMethods()
if err != nil { ms = []string{"*"} } // accepts all

Defensive patterns

Strategy: try-catch

Validate before calling

ms, err := route.GetMethods()
if err != nil { ms = []string{"*"} } // accepts all methods

Type guard

func hasMethods(rt *mux.Route) bool { _, err := rt.GetMethods(); return err == nil }

Try / catch

ms, err := rt.GetMethods()
if err != nil { ms = nil }

Prevention

Always declare Methods on routes meant for docs.
Treat the error as a wildcard.
Defensive introspection.

When it happens

Trigger: Calling GetMethods() on a route with no method constraint, e.g. r.HandleFunc("/health", h) without .Methods(...).

Common situations: OpenAPI generators expecting every route to declare verbs; metrics labeling; routes relying on a catch-all handler.

Related errors

AI-assisted analysis of gorilla/mux@db9d1d0073 (2026-08-04). Data as JSON: /data/errors/b31fce42032430af.json. Report an issue: GitHub.