Fix API dashboard using implicit default HTTP client

docs/configuration/service/api.md

@@ -92,20 +92,11 @@ Download URL of the dashboard archive (zip).
 
 ##### http_client
 
-HTTP client used to download the dashboard, with the same behavior as remote rule-sets.
+HTTP client used to download the dashboard.
 
 See [HTTP Client Fields](/configuration/shared/http-client/) for details.
 
-When empty, the default HTTP client is used: the one named by
-[`default_http_client`](/configuration/route/#default_http_client), or the first top-level
-`http_clients` entry when `default_http_client` is empty.
-
-!!! failure "Implicit default deprecated in sing-box 1.14.0"
-
-    When neither `http_clients` nor `default_http_client` is configured, an implicit HTTP
-    client connecting through the default outbound is used. This implicit default is
-    deprecated in sing-box 1.14.0 and will be removed in sing-box 1.16.0; define
-    `http_clients` instead.
+Not used when the dashboard directory contains user-provided files.
 
 ##### update_interval
 

docs/configuration/service/api.zh.md

@@ -87,17 +87,11 @@ API 密钥。
 
 ##### http_client
 
-用于下载仪表板的 HTTP 客户端，行为与远程规则集相同。
+用于下载仪表板的 HTTP 客户端。
 
 参阅 [HTTP 客户端字段](/zh/configuration/shared/http-client/)。
 
-留空时使用默认 HTTP 客户端：即由 [`default_http_client`](/zh/configuration/route/#default_http_client)
-指定的客户端，或当 `default_http_client` 为空时使用顶级 `http_clients` 的第一项。
-
-!!! failure "隐式默认已在 sing-box 1.14.0 废弃"
-
-    当 `http_clients` 与 `default_http_client` 均未配置时，将使用通过默认出站连接的隐式 HTTP 客户端。
-    该隐式默认已在 sing-box 1.14.0 废弃，并将在 sing-box 1.16.0 移除；请改为定义 `http_clients`。
+当仪表板目录包含用户提供的文件时不使用。
 
 ##### update_interval
 

service/api/dashboard.go

@@ -13,6 +13,7 @@ import (
 	"github.com/sagernet/sing-box/adapter"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing/common"
 	E "github.com/sagernet/sing/common/exceptions"
 	"github.com/sagernet/sing/service"
 	"github.com/sagernet/sing/service/filemanager"
@@ -78,12 +79,18 @@ func (d *dashboard) start() error {
 	if err != nil && !os.IsNotExist(err) {
 		return E.Cause(err, "read dashboard directory")
 	}
-	transport, err := d.resolveTransport()
+	status := d.loadState()
+	if status == dashboardUserProvided {
+		d.logger.Info("dashboard: serving user-provided files at ", d.path, ", auto-update disabled")
+		return nil
+	}
+	httpClientManager := service.FromContext[adapter.HTTPClientManager](d.ctx)
+	transport, err := httpClientManager.ResolveTransport(d.ctx, d.logger, common.PtrValueOrDefault(d.options.HTTPClient))
 	if err != nil {
 		return E.Cause(err, "create dashboard http client")
 	}
 	d.httpClient = &http.Client{Transport: transport}
-	go d.loopUpdate()
+	go d.loopUpdate(status)
 	return nil
 }
 
@@ -95,21 +102,6 @@ func (d *dashboard) close() error {
 	return nil
 }
 
-func (d *dashboard) resolveTransport() (adapter.HTTPTransport, error) {
-	httpClientManager := service.FromContext[adapter.HTTPClientManager](d.ctx)
-	if httpClientManager == nil {
-		return nil, E.New("missing http client manager in context")
-	}
-	if d.options.HTTPClient != nil && !d.options.HTTPClient.IsEmpty() {
-		return httpClientManager.ResolveTransport(d.ctx, d.logger, *d.options.HTTPClient)
-	}
-	defaultTransport := httpClientManager.DefaultTransport()
-	if defaultTransport == nil {
-		return nil, E.New("default http client transport is not initialized")
-	}
-	return defaultTransport, nil
-}
-
 func (d *dashboard) serveHTTP(writer http.ResponseWriter, request *http.Request) {
 	if strings.HasPrefix(request.URL.Path, dashboardRoutePrefix) {
 		d.fileServer.ServeHTTP(writer, request)
@@ -118,12 +110,7 @@ func (d *dashboard) serveHTTP(writer http.ResponseWriter, request *http.Request)
 	http.Redirect(writer, request, dashboardRoutePrefix, http.StatusFound)
 }
 
-func (d *dashboard) loopUpdate() {
-	status := d.loadState()
-	if status == dashboardUserProvided {
-		d.logger.Info("dashboard: serving user-provided files at ", d.path, ", auto-update disabled")
-		return
-	}
+func (d *dashboard) loopUpdate(status dashboardStatus) {
 	var nextUpdate time.Time
 	if status == dashboardManaged {
 		nextUpdate = d.lastUpdated.Add(d.updateInterval)