Choose best matching route available

go-martini · Apr 9, 2015 · 0384255 · 0384255
1 parent 2047b73
commit 0384255
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Showing 2 changed files with 60 additions and 24 deletions.
diff --git a/router.go b/router.go
@@ -112,15 +112,26 @@ func (r *router) AddRoute(method, pattern string, h ...Handler) Route {
 }
 
 func (r *router) Handle(res http.ResponseWriter, req *http.Request, context Context) {
+	bestMatch := NoMatch
+	var bestVals map[string]string
+	var bestRoute *route
 	for _, route := range r.getRoutes() {
-		ok, vals := route.Match(req.Method, req.URL.Path)
-		if ok {
-			params := Params(vals)
-			context.Map(params)
-			route.Handle(context, res)
-			return
+		match, vals := route.Match(req.Method, req.URL.Path)
+		if match.BetterThan(bestMatch) {
+			bestMatch = match
+			bestVals = vals
+			bestRoute = route
+			if match == ExactMatch {
+				break
+			}
 		}
 	}
+	if bestMatch != NoMatch {
+		params := Params(bestVals)
+		context.Map(params)
+		bestRoute.Handle(context, res)
+		return
+	}
 
 	// no routes exist, 404
 	c := &routeContext{context, 0, r.notFounds}
@@ -214,14 +225,38 @@ func newRoute(method string, pattern string, handlers []Handler) *route {
 	return &route
 }
 
-func (r route) MatchMethod(method string) bool {
-	return r.method == "*" || method == r.method || (method == "HEAD" && r.method == "GET")
+type RouteMatch int
+
+const (
+	NoMatch RouteMatch = iota
+	StarMatch
+	OverloadMatch
+	ExactMatch
+)
+
+//Higher number = better match
+func (r RouteMatch) BetterThan(o RouteMatch) bool {
+	return r > o
+}
+
+func (r route) MatchMethod(method string) RouteMatch {
+	switch {
+	case method == r.method:
+		return ExactMatch
+	case method == "HEAD" && r.method == "GET":
+		return OverloadMatch
+	case r.method == "*":
+		return StarMatch
+	default:
+		return NoMatch
+	}
 }
 
-func (r route) Match(method string, path string) (bool, map[string]string) {
+func (r route) Match(method string, path string) (RouteMatch, map[string]string) {
 	// add Any method matching support
-	if !r.MatchMethod(method) {
-		return false, nil
+	match := r.MatchMethod(method)
+	if match == NoMatch {
+		return match, nil
 	}
 
 	matches := r.regex.FindStringSubmatch(path)
@@ -232,9 +267,9 @@ func (r route) Match(method string, path string) (bool, map[string]string) {
 				params[name] = matches[i]
 			}
 		}
-		return true, params
+		return match, params
 	}
-	return false, nil
+	return NoMatch, nil
 }
 
 func (r *route) Validate() {

diff --git a/router_test.go b/router_test.go
@@ -236,24 +236,25 @@ var routeTests = []struct {
 	path   string
 
 	// out
-	ok     bool
+	match  RouteMatch
 	params map[string]string
 }{
-	{"GET", "/foo/123/bat/321", true, map[string]string{"bar": "123", "baz": "321"}},
-	{"POST", "/foo/123/bat/321", false, map[string]string{}},
-	{"GET", "/foo/hello/bat/world", true, map[string]string{"bar": "hello", "baz": "world"}},
-	{"GET", "foo/hello/bat/world", false, map[string]string{}},
-	{"GET", "/foo/123/bat/321/", true, map[string]string{"bar": "123", "baz": "321"}},
-	{"GET", "/foo/123/bat/321//", false, map[string]string{}},
-	{"GET", "/foo/123//bat/321/", false, map[string]string{}},
+	{"GET", "/foo/123/bat/321", ExactMatch, map[string]string{"bar": "123", "baz": "321"}},
+	{"POST", "/foo/123/bat/321", NoMatch, map[string]string{}},
+	{"GET", "/foo/hello/bat/world", ExactMatch, map[string]string{"bar": "hello", "baz": "world"}},
+	{"GET", "foo/hello/bat/world", NoMatch, map[string]string{}},
+	{"GET", "/foo/123/bat/321/", ExactMatch, map[string]string{"bar": "123", "baz": "321"}},
+	{"GET", "/foo/123/bat/321//", NoMatch, map[string]string{}},
+	{"GET", "/foo/123//bat/321/", NoMatch, map[string]string{}},
+	{"HEAD", "/foo/123/bat/321/", OverloadMatch, map[string]string{"bar": "123", "baz": "321"}},
 }
 
 func Test_RouteMatching(t *testing.T) {
 	route := newRoute("GET", "/foo/:bar/bat/:baz", nil)
 	for _, tt := range routeTests {
-		ok, params := route.Match(tt.method, tt.path)
-		if ok != tt.ok || params["bar"] != tt.params["bar"] || params["baz"] != tt.params["baz"] {
-			t.Errorf("expected: (%v, %v) got: (%v, %v)", tt.ok, tt.params, ok, params)
+		match, params := route.Match(tt.method, tt.path)
+		if match != tt.match || params["bar"] != tt.params["bar"] || params["baz"] != tt.params["baz"] {
+			t.Errorf("expected: (%v, %v) got: (%v, %v)", tt.match, tt.params, match, params)
 		}
 	}
 }