From cba12a570e8caa1fafabc2d41afc97bd7a83d758 Mon Sep 17 00:00:00 2001
From: toimtoimtoim <desinformatsioon@gmail.com>
Date: Sat, 6 Aug 2022 23:25:43 +0300
Subject: [PATCH] Allow arbitrary HTTP method types to be added as routes

---
 echo.go        |  5 +++-
 router.go      | 19 ++++++++++--
 router_test.go | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 101 insertions(+), 3 deletions(-)

diff --git a/echo.go b/echo.go
index 5b10d586e..5738578df 100644
--- a/echo.go
+++ b/echo.go
@@ -492,8 +492,11 @@ func (e *Echo) RouteNotFound(path string, h HandlerFunc, m ...MiddlewareFunc) *R
 	return e.Add(RouteNotFound, path, h, m...)
 }
 
-// Any registers a new route for all HTTP methods and path with matching handler
+// Any registers a new route for all HTTP methods (supported by Echo) and path with matching handler
 // in the router with optional route-level middleware.
+//
+// Note: this method only adds specific set of supported HTTP methods as handler and is not true
+// "catch-any-arbitrary-method" way of matching requests.
 func (e *Echo) Any(path string, handler HandlerFunc, middleware ...MiddlewareFunc) []*Route {
 	routes := make([]*Route, len(methods))
 	for i, m := range methods {
diff --git a/router.go b/router.go
index 90102a294..23c5bd3ba 100644
--- a/router.go
+++ b/router.go
@@ -51,6 +51,7 @@ type (
 		put         *routeMethod
 		trace       *routeMethod
 		report      *routeMethod
+		anyOther    map[string]*routeMethod
 		allowHeader string
 	}
 )
@@ -75,7 +76,8 @@ func (m *routeMethods) isHandler() bool {
 		m.propfind != nil ||
 		m.put != nil ||
 		m.trace != nil ||
-		m.report != nil
+		m.report != nil ||
+		len(m.anyOther) != 0
 	// RouteNotFound/404 is not considered as a handler
 }
 
@@ -121,6 +123,10 @@ func (m *routeMethods) updateAllowHeader() {
 	if m.report != nil {
 		buf.WriteString(", REPORT")
 	}
+	for method := range m.anyOther { // for simplicity, we use map and therefore order is not deterministic here
+		buf.WriteString(", ")
+		buf.WriteString(method)
+	}
 	m.allowHeader = buf.String()
 }
 
@@ -408,6 +414,15 @@ func (n *node) addMethod(method string, h *routeMethod) {
 	case RouteNotFound:
 		n.notFoundHandler = h
 		return // RouteNotFound/404 is not considered as a handler so no further logic needs to be executed
+	default:
+		if n.methods.anyOther == nil {
+			n.methods.anyOther = make(map[string]*routeMethod)
+		}
+		if h.handler == nil {
+			delete(n.methods.anyOther, method)
+		} else {
+			n.methods.anyOther[method] = h
+		}
 	}
 
 	n.methods.updateAllowHeader()
@@ -439,7 +454,7 @@ func (n *node) findMethod(method string) *routeMethod {
 	case REPORT:
 		return n.methods.report
 	default: // RouteNotFound/404 is not considered as a handler
-		return nil
+		return n.methods.anyOther[method]
 	}
 }
 
diff --git a/router_test.go b/router_test.go
index 1b0c409b6..a95421011 100644
--- a/router_test.go
+++ b/router_test.go
@@ -716,6 +716,67 @@ func TestRouterParam(t *testing.T) {
 	}
 }
 
+func TestRouter_addAndMatchAllSupportedMethods(t *testing.T) {
+	var testCases = []struct {
+		name            string
+		givenNoAddRoute bool
+		whenMethod      string
+		expectPath      string
+		expectError     string
+	}{
+		{name: "ok, CONNECT", whenMethod: http.MethodConnect},
+		{name: "ok, DELETE", whenMethod: http.MethodDelete},
+		{name: "ok, GET", whenMethod: http.MethodGet},
+		{name: "ok, HEAD", whenMethod: http.MethodHead},
+		{name: "ok, OPTIONS", whenMethod: http.MethodOptions},
+		{name: "ok, PATCH", whenMethod: http.MethodPatch},
+		{name: "ok, POST", whenMethod: http.MethodPost},
+		{name: "ok, PROPFIND", whenMethod: PROPFIND},
+		{name: "ok, PUT", whenMethod: http.MethodPut},
+		{name: "ok, TRACE", whenMethod: http.MethodTrace},
+		{name: "ok, REPORT", whenMethod: REPORT},
+		{name: "ok, NON_TRADITIONAL_METHOD", whenMethod: "NON_TRADITIONAL_METHOD"},
+		{
+			name:            "ok, NOT_EXISTING_METHOD",
+			whenMethod:      "NOT_EXISTING_METHOD",
+			givenNoAddRoute: true,
+			expectPath:      "/*",
+			expectError:     "code=405, message=Method Not Allowed",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			e := New()
+
+			e.GET("/*", handlerFunc)
+
+			if !tc.givenNoAddRoute {
+				e.Add(tc.whenMethod, "/my/*", handlerFunc)
+			}
+
+			req := httptest.NewRequest(tc.whenMethod, "/my/some-url", nil)
+			rec := httptest.NewRecorder()
+			c := e.NewContext(req, rec).(*context)
+
+			e.router.Find(tc.whenMethod, "/my/some-url", c)
+			err := c.handler(c)
+
+			if tc.expectError != "" {
+				assert.EqualError(t, err, tc.expectError)
+			} else {
+				assert.NoError(t, err)
+			}
+
+			expectPath := "/my/*"
+			if tc.expectPath != "" {
+				expectPath = tc.expectPath
+			}
+			assert.Equal(t, expectPath, c.Path())
+		})
+	}
+}
+
 func TestMethodNotAllowedAndNotFound(t *testing.T) {
 	e := New()
 	r := e.router
@@ -2634,6 +2695,25 @@ func TestRouterHandleMethodOptions(t *testing.T) {
 	}
 }
 
+func TestRouterAllowHeaderForAnyOtherMethodType(t *testing.T) {
+	e := New()
+	r := e.router
+
+	r.Add(http.MethodGet, "/users", handlerFunc)
+	r.Add("COPY", "/users", handlerFunc)
+	r.Add("LOCK", "/users", handlerFunc)
+
+	req := httptest.NewRequest("TEST", "/users", nil)
+	rec := httptest.NewRecorder()
+	c := e.NewContext(req, rec).(*context)
+
+	r.Find("TEST", "/users", c)
+	err := c.handler(c)
+
+	assert.EqualError(t, err, "code=405, message=Method Not Allowed")
+	assert.ElementsMatch(t, []string{"COPY", "GET", "LOCK", "OPTIONS"}, strings.Split(c.Response().Header().Get(HeaderAllow), ", "))
+}
+
 func benchmarkRouterRoutes(b *testing.B, routes []*Route, routesToFind []*Route) {
 	e := New()
 	r := e.router