chore: store latency data more reasonably (#964)

adapter/adapter.go

@@ -3,7 +3,6 @@ package adapter
 import (
 	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"net"
 	"net/http"
@@ -163,6 +162,8 @@ func (p *Proxy) MarshalJSON() ([]byte, error) {
 // URLTest get the delay for the specified URL
 // implements C.Proxy
 func (p *Proxy) URLTest(ctx context.Context, url string, expectedStatus utils.IntRanges[uint16]) (t uint16, err error) {
+	var satisfied bool
+
 	defer func() {
 		alive := err == nil
 		record := C.DelayHistory{Time: time.Now()}
@@ -185,6 +186,11 @@ func (p *Proxy) URLTest(ctx context.Context, url string, expectedStatus utils.In
 			p.extra.Store(url, state)
 		}
 
+		if !satisfied {
+			record.Delay = 0
+			alive = false
+		}
+
 		state.alive.Store(alive)
 		state.history.Put(record)
 		if state.history.Len() > defaultHistoriesNum {
@@ -253,15 +259,10 @@ func (p *Proxy) URLTest(ctx context.Context, url string, expectedStatus utils.In
 		}
 	}
 
-	if expectedStatus != nil && !expectedStatus.Check(uint16(resp.StatusCode)) {
-		// maybe another value should be returned for differentiation
-		err = errors.New("response status is inconsistent with the expected status")
-	}
-
+	satisfied = resp != nil && (expectedStatus == nil || expectedStatus.Check(uint16(resp.StatusCode)))
 	t = uint16(time.Since(start) / time.Millisecond)
 	return
 }
-
 func NewProxy(adapter C.ProxyAdapter) *Proxy {
 	return &Proxy{
 		ProxyAdapter: adapter,