Call Close on user values stored via RequestCtx.SetUserValue if these values implement io.Closer

server.go

@@ -359,7 +359,9 @@ func (ctx *RequestCtx) Hijack(handler HijackHandler) {
 // This functionality may be useful for passing arbitrary values between
 // functions involved in request processing.
 //
-// All the values stored in ctx are deleted after returning from RequestHandler.
+// All the values are removed from ctx after returning from the top
+// RequestHandler. Additionally, Close method is called on each value
+// implementing io.Closer before removing the value from ctx.
 func (ctx *RequestCtx) SetUserValue(key string, value interface{}) {
 	ctx.userValues.Set(key, value)
 }

userdata.go

@@ -1,5 +1,9 @@
 package fasthttp
 
+import (
+	"io"
+)
+
 type userDataKV struct {
 	key   []byte
 	value interface{}
@@ -55,5 +59,13 @@ func (d *userData) GetBytes(key []byte) interface{} {
 }
 
 func (d *userData) Reset() {
+	args := *d
+	n := len(args)
+	for i := 0; i < n; i++ {
+		v := args[i].value
+		if vc, ok := v.(io.Closer); ok {
+			vc.Close()
+		}
+	}
 	*d = (*d)[:0]
 }

userdata_test.go

@@ -39,3 +39,36 @@ func testUserDataGet(t *testing.T, u *userData, key []byte, value interface{}) {
 		t.Fatalf("unexpected value for key=%q: %d. Expecting %d", key, v, value)
 	}
 }
+
+func TestUserDataValueClose(t *testing.T) {
+	var u userData
+
+	closeCalls := 0
+
+	// store values implementing io.Closer
+	for i := 0; i < 5; i++ {
+		key := fmt.Sprintf("key_%d", i)
+		u.Set(key, &closerValue{&closeCalls})
+	}
+
+	// store values without io.Closer
+	for i := 0; i < 10; i++ {
+		key := fmt.Sprintf("key_noclose_%d", i)
+		u.Set(key, i)
+	}
+
+	u.Reset()
+
+	if closeCalls != 5 {
+		t.Fatalf("unexpected number of Close calls: %d. Expecting 10", closeCalls)
+	}
+}
+
+type closerValue struct {
+	closeCalls *int
+}
+
+func (cv *closerValue) Close() error {
+	(*cv.closeCalls)++
+	return nil
+}