X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/1e31ae09539d8265820a2f75f8a981f7d415ef58..78e0599b0773976167ccb720fc1596236295337a:/services/keepproxy/keepproxy.go

diff --git a/services/keepproxy/keepproxy.go b/services/keepproxy/keepproxy.go
index ea14c6ca48..581f7f4873 100644
--- a/services/keepproxy/keepproxy.go
+++ b/services/keepproxy/keepproxy.go
@@ -134,16 +134,27 @@ type ApiTokenCache struct {
 
 // Refresh the keep service list every five minutes.
 func RefreshServicesList(kc *keepclient.KeepClient) {
+	var sleeptime time.Duration
 	for {
-		time.Sleep(300 * time.Second)
 		oldservices := kc.ServiceRoots()
-		kc.DiscoverKeepServers()
-		newservices := kc.ServiceRoots()
-		s1 := fmt.Sprint(oldservices)
-		s2 := fmt.Sprint(newservices)
-		if s1 != s2 {
-			log.Printf("Updated server list to %v", s2)
+		newservices, err := kc.DiscoverKeepServers()
+		if err == nil && len(newservices) > 0 {
+			s1 := fmt.Sprint(oldservices)
+			s2 := fmt.Sprint(newservices)
+			if s1 != s2 {
+				log.Printf("Updated server list to %v", s2)
+			}
+			sleeptime = 300 * time.Second
+		} else {
+			// There was an error, or the list is empty, so wait 3 seconds and try again.
+			if err != nil {
+				log.Printf("Error retrieving server list: %v", err)
+			} else {
+				log.Printf("Retrieved an empty server list")
+			}
+			sleeptime = 3 * time.Second
 		}
+		time.Sleep(sleeptime)
 	}
 }
 
@@ -312,14 +323,14 @@ func (this GetBlockHandler) ServeHTTP(resp http.ResponseWriter, req *http.Reques
 
 	if req.Method == "GET" {
 		reader, blocklen, _, err = kc.AuthorizedGet(hash, locator.Signature, locator.Timestamp)
-		defer reader.Close()
+		if reader != nil {
+			defer reader.Close()
+		}
 	} else if req.Method == "HEAD" {
 		blocklen, _, err = kc.AuthorizedAsk(hash, locator.Signature, locator.Timestamp)
 	}
 
-	if blocklen > -1 {
-		resp.Header().Set("Content-Length", fmt.Sprint(blocklen))
-	} else {
+	if blocklen == -1 {
 		log.Printf("%s: %s %s Keep server did not return Content-Length",
 			GetRemoteAddress(req), req.Method, hash)
 	}
@@ -328,6 +339,7 @@ func (this GetBlockHandler) ServeHTTP(resp http.ResponseWriter, req *http.Reques
 	switch err {
 	case nil:
 		status = http.StatusOK
+		resp.Header().Set("Content-Length", fmt.Sprint(blocklen))
 		if reader != nil {
 			n, err2 := io.Copy(resp, reader)
 			if blocklen > -1 && n != blocklen {
@@ -345,7 +357,7 @@ func (this GetBlockHandler) ServeHTTP(resp http.ResponseWriter, req *http.Reques
 		}
 	case keepclient.BlockNotFound:
 		status = http.StatusNotFound
-		http.Error(resp, "Not found", http.StatusNotFound)
+		http.Error(resp, "Not Found", http.StatusNotFound)
 	default:
 		status = http.StatusBadGateway
 		http.Error(resp, err.Error(), http.StatusBadGateway)