Show "Your resilient single server can now be accessed with ..." message only on leader

Author: ewoutp

CHANGELOG.md

@@ -1,5 +1,6 @@
 # Changes from version 0.10.4 to master
 
+- For `activefailover` deployments, the message where to reach your database is now only shown for the current leader.
 - Added `--log.dir` option to configure a custom directory to which all log files will be written.
 - It is no longer allowed to use `log.file` as a passthrough option.
 - Added `--starter.host` option, to bind the HTTP server to a specific network interface instead of the default `0.0.0.0`.

service/runtime_server_manager.go

@@ -75,7 +75,7 @@ type runtimeServerManagerContext interface {
 
 	// TestInstance checks the `up` status of an arangod server instance.
 	TestInstance(ctx context.Context, serverType ServerType, address string, port int,
-		statusChanged chan StatusItem) (up, correctRole bool, version, role, mode string, statusTrail []int, cancelled bool)
+		statusChanged chan StatusItem) (up, correctRole bool, version, role, mode string, isLeader bool, statusTrail []int, cancelled bool)
 
 	// IsLocalSlave returns true if this peer is running as a local slave
 	IsLocalSlave() bool
@@ -116,7 +116,7 @@ func startServer(ctx context.Context, log *logging.Logger, runtimeContext runtim
 	if p != nil {
 		log.Infof("%s seems to be running already, checking port %d...", serverType, myPort)
 		ctx, cancel := context.WithTimeout(context.Background(), time.Second*10)
-		up, correctRole, _, _, _, _, _ := runtimeContext.TestInstance(ctx, serverType, myHostAddress, myPort, nil)
+		up, correctRole, _, _, _, _, _, _ := runtimeContext.TestInstance(ctx, serverType, myHostAddress, myPort, nil)
 		cancel()
 		if up && correctRole {
 			log.Infof("%s is already running on %d. No need to start anything.", serverType, myPort)
@@ -271,7 +271,7 @@ func (s *runtimeServerManager) runServer(ctx context.Context, log *logging.Logge
 						}
 					}
 				}()
-				if up, correctRole, version, role, mode, statusTrail, cancelled := runtimeContext.TestInstance(ctx, serverType, myHostAddress, port, statusChanged); !cancelled {
+				if up, correctRole, version, role, mode, isLeader, statusTrail, cancelled := runtimeContext.TestInstance(ctx, serverType, myHostAddress, port, statusChanged); !cancelled {
 					if up && correctRole {
 						log.Infof("%s up and running (version %s).", serverType, version)
 						if (serverType == ServerTypeCoordinator && !runtimeContext.IsLocalSlave()) || serverType == ServerTypeSingle || serverType == ServerTypeResilientSingle {
@@ -289,10 +289,12 @@ func (s *runtimeServerManager) runServer(ctx context.Context, log *logging.Logge
 								} else if serverType == ServerTypeResilientSingle {
 									what = "resilient single server"
 								}
-								s.logMutex.Lock()
-								log.Infof("Your %s can now be accessed with a browser at `%s://%s:%d` or", what, urlSchemes.Browser, ip, hostPort)
-								log.Infof("using `arangosh --server.endpoint %s://%s:%d`.", urlSchemes.ArangoSH, ip, hostPort)
-								s.logMutex.Unlock()
+								if serverType != ServerTypeResilientSingle || isLeader {
+									s.logMutex.Lock()
+									log.Infof("Your %s can now be accessed with a browser at `%s://%s:%d` or", what, urlSchemes.Browser, ip, hostPort)
+									log.Infof("using `arangosh --server.endpoint %s://%s:%d`.", urlSchemes.ArangoSH, ip, hostPort)
+									s.logMutex.Unlock()
+								}
 								runtimeContext.removeRecoveryFile()
 							}
 						}

service/service.go

@@ -542,14 +542,15 @@ type StatusItem struct {
 }
 
 type instanceUpInfo struct {
-	Version string
-	Role    string
-	Mode    string
+	Version  string
+	Role     string
+	Mode     string
+	IsLeader bool
 }
 
 // TestInstance checks the `up` status of an arangod server instance.
 func (s *Service) TestInstance(ctx context.Context, serverType ServerType, address string, port int,
-	statusChanged chan StatusItem) (up, correctRole bool, version, role, mode string, statusTrail []int, cancelled bool) {
+	statusChanged chan StatusItem) (up, correctRole bool, version, role, mode string, isLeader bool, statusTrail []int, cancelled bool) {
 	instanceUp := make(chan instanceUpInfo)
 	statusCodes := make(chan int)
 	if statusChanged != nil {
@@ -666,14 +667,42 @@ func (s *Service) TestInstance(ctx context.Context, serverType ServerType, addre
 			}
 			return roleResponse.Role, roleResponse.Mode, resp.StatusCode, nil
 		}
+		makeIsLeaderRequest := func() (bool, error) {
+			if serverType != ServerTypeResilientSingle {
+				return false, nil
+			}
+			addr := net.JoinHostPort(address, strconv.Itoa(port))
+			url := fmt.Sprintf("%s://%s/_api/database", scheme, addr)
+			req, err := http.NewRequest("GET", url, nil)
+			if err != nil {
+				return false, maskAny(err)
+			}
+			if err := addJwtHeader(req, s.jwtSecret); err != nil {
+				return false, maskAny(err)
+			}
+			resp, err := client.Do(req)
+			if err != nil {
+				return false, maskAny(err)
+			}
+			if resp.StatusCode == 200 {
+				return true, nil
+			}
+			if resp.StatusCode == 503 && resp.Header.Get("X-Arango-Endpoint") != "" {
+				return false, nil
+			}
+			return false, maskAny(fmt.Errorf("Invalid status %d", resp.StatusCode))
+		}
 
 		for i := 0; i < 300; i++ {
 			if version, statusCode, err := makeVersionRequest(); err == nil {
 				if role, mode, statusCode, err := makeRoleRequest(); err == nil {
-					instanceUp <- instanceUpInfo{
-						Version: version,
-						Role:    role,
-						Mode:    mode,
+					if isLeader, err := makeIsLeaderRequest(); err == nil {
+						instanceUp <- instanceUpInfo{
+							Version:  version,
+							Role:     role,
+							Mode:     mode,
+							IsLeader: isLeader,
+						}
 					}
 				} else {
 					statusCodes <- statusCode
@@ -695,7 +724,7 @@ func (s *Service) TestInstance(ctx context.Context, serverType ServerType, addre
 			up = instanceInfo.Version != ""
 			correctRole = instanceInfo.Role == expectedRole || expectedRole == ""
 			correctMode := instanceInfo.Mode == expectedMode || expectedMode == ""
-			return up, correctRole && correctMode, instanceInfo.Version, instanceInfo.Role, instanceInfo.Mode, statusTrail, false
+			return up, correctRole && correctMode, instanceInfo.Version, instanceInfo.Role, instanceInfo.Mode, instanceInfo.IsLeader, statusTrail, false
 		case statusCode := <-statusCodes:
 			lastStatusCode := math.MinInt32
 			if len(statusTrail) > 0 {
@@ -712,7 +741,7 @@ func (s *Service) TestInstance(ctx context.Context, serverType ServerType, addre
 				}
 			}
 		case <-ctx.Done():
-			return false, false, "", "", "", statusTrail, true
+			return false, false, "", "", "", false, statusTrail, true
 		}
 	}
 }

start.go

@@ -137,7 +137,7 @@ func cmdStartRun(cmd *cobra.Command, args []string) {
 				allUp := true
 				for _, server := range list.Servers {
 					ctx, cancel := context.WithTimeout(rootCtx, time.Second)
-					up, _, _, _, _, _, _ := service.TestInstance(ctx, svc.ServerType(server.Type), server.IP, server.Port, nil)
+					up, _, _, _, _, _, _, _ := service.TestInstance(ctx, svc.ServerType(server.Type), server.IP, server.Port, nil)
 					cancel()
 					if !up {
 						allUp = false