Regex capturing group.

vendor/github.com/containous/mux/route.go

@@ -54,12 +54,27 @@ func (r *Route) Match(req *http.Request, match *RouteMatch) bool {
 	if r.buildOnly || r.err != nil {
 		return false
 	}
+
+	var matchErr error
+
 	// Match everything.
 	for _, m := range r.matchers {
 		if matched := m.Match(req, match); !matched {
+			if _, ok := m.(methodMatcher); ok {
+				matchErr = ErrMethodMismatch
+				continue
+			}
+			matchErr = nil
 			return false
 		}
 	}
+
+	if matchErr != nil {
+		match.MatchErr = matchErr
+		return false
+	}
+
+	match.MatchErr = nil
 	// Yay, we have a match. Let's collect some info about it.
 	if match.Route == nil {
 		match.Route = r
@@ -70,6 +85,7 @@ func (r *Route) Match(req *http.Request, match *RouteMatch) bool {
 	if match.Vars == nil {
 		match.Vars = make(map[string]string)
 	}
+
 	// Set variables.
 	if r.regexp != nil {
 		r.regexp.setMatch(req, match, r)
@@ -607,6 +623,44 @@ func (r *Route) GetPathRegexp() (string, error) {
 	return r.regexp.path.regexp.String(), nil
 }
 
+// GetQueriesRegexp returns the expanded regular expressions used to match the
+// route queries.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An empty list will be returned if the route does not have queries.
+func (r *Route) GetQueriesRegexp() ([]string, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.queries == nil {
+		return nil, errors.New("mux: route doesn't have queries")
+	}
+	var queries []string
+	for _, query := range r.regexp.queries {
+		queries = append(queries, query.regexp.String())
+	}
+	return queries, nil
+}
+
+// GetQueriesTemplates returns the templates used to build the
+// query matching.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An empty list will be returned if the route does not define queries.
+func (r *Route) GetQueriesTemplates() ([]string, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.queries == nil {
+		return nil, errors.New("mux: route doesn't have queries")
+	}
+	var queries []string
+	for _, query := range r.regexp.queries {
+		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.