diff --git a/internal/api/handler.go b/internal/api/handler.go
index f8ea7b0..af76837 100644
--- a/internal/api/handler.go
+++ b/internal/api/handler.go
@@ -30,9 +30,9 @@ func NewHandler(cfg *config.Config) http.Handler {
 	mux.HandleFunc("GET", "/v1/list", wrap(cfg, v1.List))
 	mux.HandleFunc("GET", "/v1/list/{what}", wrap(cfg, v1.List))
 	mux.HandleFunc("GET", "/v1/file", v1.GetFileContent)
-	mux.HandleFunc("GET", "/v1/file/{filename}", v1.GetFileContent)
-	mux.HandleFunc("POST", "/v1/file/{filename}", v1.SetFileContent)
-	mux.HandleFunc("PUT", "/v1/file/{filename}", v1.SetFileContent)
+	mux.HandleFunc("GET", "/v1/file/{filename...}", v1.GetFileContent)
+	mux.HandleFunc("POST", "/v1/file/{filename...}", v1.SetFileContent)
+	mux.HandleFunc("PUT", "/v1/file/{filename...}", v1.SetFileContent)
 	mux.HandleFunc("GET", "/v1/stats", wrap(cfg, v1.Stats))
 	mux.HandleFunc("GET", "/v1/error_page", error_page.GetHandleFunc())
 	return mux
diff --git a/internal/api/v1/file.go b/internal/api/v1/file.go
index ed17b0d..e413ae5 100644
--- a/internal/api/v1/file.go
+++ b/internal/api/v1/file.go
@@ -5,6 +5,7 @@ import (
 	"net/http"
 	"os"
 	"path"
+	"strings"
 
 	U "github.com/yusing/go-proxy/internal/api/v1/utils"
 	"github.com/yusing/go-proxy/internal/common"
@@ -41,7 +42,7 @@ func SetFileContent(w http.ResponseWriter, r *http.Request) {
 	var validateErr E.NestedError
 	if filename == common.ConfigFileName {
 		validateErr = config.Validate(content)
-	} else {
+	} else if !strings.HasPrefix(filename, path.Base(common.MiddlewareComposeBasePath)) {
 		validateErr = provider.Validate(content)
 	}
 
diff --git a/internal/api/v1/list.go b/internal/api/v1/list.go
index 1550d50..3317646 100644
--- a/internal/api/v1/list.go
+++ b/internal/api/v1/list.go
@@ -1,19 +1,20 @@
 package v1
 
 import (
-	"encoding/json"
 	"net/http"
-	"os"
+	"strings"
 
 	U "github.com/yusing/go-proxy/internal/api/v1/utils"
 	"github.com/yusing/go-proxy/internal/common"
 	"github.com/yusing/go-proxy/internal/config"
 	"github.com/yusing/go-proxy/internal/net/http/middleware"
+	"github.com/yusing/go-proxy/internal/utils"
 )
 
 const (
 	ListRoutes          = "routes"
 	ListConfigFiles     = "config_files"
+	ListMiddlewares     = "middlewares"
 	ListMiddlewareTrace = "middleware_trace"
 )
 
@@ -28,6 +29,8 @@ func List(cfg *config.Config, w http.ResponseWriter, r *http.Request) {
 		listRoutes(cfg, w, r)
 	case ListConfigFiles:
 		listConfigFiles(w, r)
+	case ListMiddlewares:
+		listMiddlewares(w, r)
 	case ListMiddlewareTrace:
 		listMiddlewareTrace(w, r)
 	default:
@@ -46,34 +49,25 @@ func listRoutes(cfg *config.Config, w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	if err := U.RespondJson(w, routes); err != nil {
-		U.HandleErr(w, r, err)
-	}
+	U.HandleErr(w, r, U.RespondJson(w, routes))
 }
 
 func listConfigFiles(w http.ResponseWriter, r *http.Request) {
-	files, err := os.ReadDir(common.ConfigBasePath)
+	files, err := utils.ListFiles(common.ConfigBasePath, 1)
 	if err != nil {
 		U.HandleErr(w, r, err)
 		return
 	}
-	filenames := make([]string, len(files))
-	for i, f := range files {
-		filenames[i] = f.Name()
+	for i := range files {
+		files[i] = strings.TrimPrefix(files[i], common.ConfigBasePath+"/")
 	}
-	resp, err := json.Marshal(filenames)
-	if err != nil {
-		U.HandleErr(w, r, err)
-		return
-	}
-	w.Write(resp)
+	U.HandleErr(w, r, U.RespondJson(w, files))
 }
 
 func listMiddlewareTrace(w http.ResponseWriter, r *http.Request) {
-	resp, err := json.Marshal(middleware.GetAllTrace())
-	if err != nil {
-		U.HandleErr(w, r, err)
-		return
-	}
-	w.Write(resp)
+	U.HandleErr(w, r, U.RespondJson(w, middleware.GetAllTrace()))
+}
+
+func listMiddlewares(w http.ResponseWriter, r *http.Request) {
+	U.HandleErr(w, r, U.RespondJson(w, middleware.All()))
 }
diff --git a/internal/api/v1/utils/error.go b/internal/api/v1/utils/error.go
index 1a9f58c..957e6cd 100644
--- a/internal/api/v1/utils/error.go
+++ b/internal/api/v1/utils/error.go
@@ -12,6 +12,9 @@ import (
 var Logger = logrus.WithField("module", "api")
 
 func HandleErr(w http.ResponseWriter, r *http.Request, origErr error, code ...int) {
+	if origErr == nil {
+		return
+	}
 	err := E.From(origErr).Subjectf("%s %s", r.Method, r.URL)
 	Logger.Error(err)
 	if len(code) > 0 {
diff --git a/internal/config/query.go b/internal/config/query.go
index 0337699..cef4182 100644
--- a/internal/config/query.go
+++ b/internal/config/query.go
@@ -38,6 +38,7 @@ func (cfg *Config) RoutesByAlias() map[string]U.SerializedObject {
 		obj["provider"] = p.GetName()
 		obj["type"] = string(r.Type())
 		obj["started"] = r.Started()
+		obj["raw"] = r.Entry()
 		routes[alias] = obj
 	})
 	return routes
@@ -46,30 +47,17 @@ func (cfg *Config) RoutesByAlias() map[string]U.SerializedObject {
 func (cfg *Config) Statistics() map[string]any {
 	nTotalStreams := 0
 	nTotalRPs := 0
-	providerStats := make(map[string]any)
+	providerStats := make(map[string]PR.ProviderStats)
 
-	cfg.forEachRoute(func(alias string, r R.Route, p *PR.Provider) {
-		if !r.Started() {
-			return
-		}
-		s, ok := providerStats[p.GetName()]
-		if !ok {
-			s = make(map[string]int)
-		}
-
-		stats := s.(map[string]int)
-		switch r.Type() {
-		case R.RouteTypeStream:
-			stats["num_streams"]++
-			nTotalStreams++
-		case R.RouteTypeReverseProxy:
-			stats["num_reverse_proxies"]++
-			nTotalRPs++
-		default:
-			panic("bug: should not reach here")
-		}
+	cfg.proxyProviders.RangeAll(func(name string, p *PR.Provider) {
+		providerStats[name] = p.Statistics()
 	})
 
+	for _, stats := range providerStats {
+		nTotalRPs += stats.NumRPs
+		nTotalStreams += stats.NumStreams
+	}
+
 	return map[string]any{
 		"num_total_streams":         nTotalStreams,
 		"num_total_reverse_proxies": nTotalRPs,
diff --git a/internal/net/http/middleware/middlewares.go b/internal/net/http/middleware/middlewares.go
index ada30b9..aebec82 100644
--- a/internal/net/http/middleware/middlewares.go
+++ b/internal/net/http/middleware/middlewares.go
@@ -20,6 +20,10 @@ func Get(name string) (middleware *Middleware, ok bool) {
 	return
 }
 
+func All() map[string]*Middleware {
+	return middlewares
+}
+
 // initialize middleware names and label parsers
 func init() {
 	middlewares = map[string]*Middleware{
diff --git a/internal/proxy/provider/provider.go b/internal/proxy/provider/provider.go
index a637422..b58cdc8 100644
--- a/internal/proxy/provider/provider.go
+++ b/internal/proxy/provider/provider.go
@@ -31,8 +31,13 @@ type (
 		OnEvent(event W.Event, routes R.Routes) EventResult
 		String() string
 	}
-	ProviderType string
-	EventResult  struct {
+	ProviderType  string
+	ProviderStats struct {
+		NumRPs     int          `json:"num_reverse_proxies"`
+		NumStreams int          `json:"num_streams"`
+		Type       ProviderType `json:"type"`
+	}
+	EventResult struct {
 		nRemoved int
 		nAdded   int
 		err      E.NestedError
@@ -164,6 +169,24 @@ func (p *Provider) LoadRoutes() E.NestedError {
 	return E.FailWith("loading routes", err)
 }
 
+func (p *Provider) Statistics() ProviderStats {
+	numRPs := 0
+	numStreams := 0
+	p.routes.RangeAll(func(_ string, r R.Route) {
+		switch r.Type() {
+		case R.RouteTypeReverseProxy:
+			numRPs++
+		case R.RouteTypeStream:
+			numStreams++
+		}
+	})
+	return ProviderStats{
+		NumRPs:     numRPs,
+		NumStreams: numStreams,
+		Type:       p.t,
+	}
+}
+
 func (p *Provider) watchEvents() {
 	p.watcherCtx, p.watcherCancel = context.WithCancel(context.Background())
 	events, errs := p.watcher.Events(p.watcherCtx)
diff --git a/internal/utils/fs.go b/internal/utils/fs.go
index 09855df..2332220 100644
--- a/internal/utils/fs.go
+++ b/internal/utils/fs.go
@@ -23,9 +23,7 @@ func ListFiles(dir string, maxDepth int) ([]string, error) {
 			if err != nil {
 				return nil, err
 			}
-			for _, subEntry := range subEntries {
-				files = append(files, path.Join(dir, entry.Name(), subEntry))
-			}
+			files = append(files, subEntries...)
 		} else {
 			files = append(files, path.Join(dir, entry.Name()))
 		}