[#257] Add policy checker

Signed-off-by: Denis Kirillov <d.kirillov@yadro.com>

api/middleware/metrics.go

@@ -35,7 +35,7 @@ type (
 		startTime  time.Time
 	}
 
-	AliasResolver interface {
+	MetricsSettings interface {
 		ResolveNamespaceAlias(namespace string) string
 	}
 
@@ -49,14 +49,14 @@ type (
 const systemPath = "/system"
 
 // Metrics wraps http handler for api with basic statistics collection.
-func Metrics(log *zap.Logger, resolveBucket BucketResolveFunc, appMetrics *metrics.AppMetrics, aliasResolver AliasResolver) Func {
+func Metrics(log *zap.Logger, resolveBucket BucketResolveFunc, appMetrics *metrics.AppMetrics, settings MetricsSettings) Func {
 	return func(h http.Handler) http.Handler {
-		return stats(h.ServeHTTP, resolveCID(log, resolveBucket), appMetrics, aliasResolver)
+		return stats(h.ServeHTTP, resolveCID(log, resolveBucket), appMetrics, settings)
 	}
 }
 
 // Stats is a handler that update metrics.
-func stats(f http.HandlerFunc, resolveCID cidResolveFunc, appMetrics *metrics.AppMetrics, aliasResolver AliasResolver) http.HandlerFunc {
+func stats(f http.HandlerFunc, resolveCID cidResolveFunc, appMetrics *metrics.AppMetrics, settings MetricsSettings) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		reqInfo := GetReqInfo(r.Context())
 
@@ -82,7 +82,7 @@ func stats(f http.HandlerFunc, resolveCID cidResolveFunc, appMetrics *metrics.Ap
 
 		user := resolveUser(r.Context())
 		cnrID := resolveCID(r.Context(), reqInfo)
-		appMetrics.Update(user, reqInfo.BucketName, cnrID, aliasResolver.ResolveNamespaceAlias(reqInfo.Namespace),
+		appMetrics.Update(user, reqInfo.BucketName, cnrID, settings.ResolveNamespaceAlias(reqInfo.Namespace),
 			requestTypeFromAPI(reqInfo.API), in.countBytes, out.countBytes)
 
 		code := statsWriter.statusCode