admin: Add ServerInfo API() (#3743)

cmd/admin-handlers.go

@@ -188,6 +188,98 @@ func (adminAPI adminAPIHandlers) ServiceCredentialsHandler(w http.ResponseWriter
 	w.WriteHeader(http.StatusOK)
 }
 
+// ServerProperties holds some server information such as, version, region
+// uptime, etc..
+type ServerProperties struct {
+	Uptime   time.Duration `json:"uptime"`
+	Version  string        `json:"version"`
+	CommitID string        `json:"commitID"`
+	Region   string        `json:"region"`
+	SQSARN   []string      `json:"sqsARN"`
+}
+
+// ServerConnStats holds transferred bytes from/to the server
+type ServerConnStats struct {
+	TotalInputBytes  uint64 `json:"transferred"`
+	TotalOutputBytes uint64 `json:"received"`
+	Throughput       uint64 `json:"throughput,omitempty"`
+}
+
+// ServerInfo holds the information that will be returned by ServerInfo API
+type ServerInfo struct {
+	StorageInfo StorageInfo      `json:"storage"`
+	ConnStats   ServerConnStats  `json:"network"`
+	Properties  ServerProperties `json:"server"`
+}
+
+// ServerInfoHandler - GET /?server-info
+// ----------
+// Get server information
+func (adminAPI adminAPIHandlers) ServerInfoHandler(w http.ResponseWriter, r *http.Request) {
+	// Authenticate request
+	adminAPIErr := checkRequestAuthType(r, "", "", "")
+	if adminAPIErr != ErrNone {
+		writeErrorResponse(w, adminAPIErr, r.URL)
+		return
+	}
+
+	// Build storage info
+	objLayer := newObjectLayerFn()
+	if objLayer == nil {
+		writeErrorResponse(w, ErrServerNotInitialized, r.URL)
+		return
+	}
+	storage := objLayer.StorageInfo()
+
+	// Build list of enabled ARNs queues
+	var arns []string
+	for queueArn := range globalEventNotifier.GetAllExternalTargets() {
+		arns = append(arns, queueArn)
+	}
+
+	// Fetch uptimes from all peers. This may fail to due to lack
+	// of read-quorum availability.
+	uptime, err := getPeerUptimes(globalAdminPeers)
+	if err != nil {
+		writeErrorResponse(w, toAPIErrorCode(err), r.URL)
+		errorIf(err, "Unable to get uptime from majority of servers.")
+		return
+	}
+
+	// Build server properties information
+	properties := ServerProperties{
+		Version:  Version,
+		CommitID: CommitID,
+		Region:   serverConfig.GetRegion(),
+		SQSARN:   arns,
+		Uptime:   uptime,
+	}
+
+	// Build network info
+	connStats := ServerConnStats{
+		TotalInputBytes:  globalConnStats.getTotalInputBytes(),
+		TotalOutputBytes: globalConnStats.getTotalOutputBytes(),
+	}
+
+	// Build the whole returned information
+	info := ServerInfo{
+		StorageInfo: storage,
+		ConnStats:   connStats,
+		Properties:  properties,
+	}
+
+	// Marshal API response
+	jsonBytes, err := json.Marshal(info)
+	if err != nil {
+		writeErrorResponse(w, ErrInternalError, r.URL)
+		errorIf(err, "Failed to marshal storage info into json.")
+		return
+	}
+	// Reply with storage information (across nodes in a
+	// distributed setup) as json.
+	writeSuccessResponseJSON(w, jsonBytes)
+}
+
 // validateLockQueryParams - Validates query params for list/clear locks management APIs.
 func validateLockQueryParams(vars url.Values) (string, string, time.Duration, APIErrorCode) {
 	bucket := vars.Get(string(mgmtBucket))

cmd/admin-router.go

@@ -39,6 +39,9 @@ func registerAdminRouter(mux *router.Router) {
 	// Service update credentials
 	adminRouter.Methods("POST").Queries("service", "").Headers(minioAdminOpHeader, "set-credentials").HandlerFunc(adminAPI.ServiceCredentialsHandler)
 
+	// Info operations
+	adminRouter.Methods("GET").Queries("info", "").HandlerFunc(adminAPI.ServerInfoHandler)
+
 	/// Lock operations
 
 	// List Locks

cmd/event-notifier.go

@@ -162,9 +162,22 @@ func newNotificationEvent(event eventData) NotificationEvent {
 	return nEvent
 }
 
-// Fetch the external target. No locking needed here since this map is
-// never written after initial startup.
+// Fetch all external targets. This returns a copy of the current map of
+// external notification targets.
+func (en eventNotifier) GetAllExternalTargets() map[string]*logrus.Logger {
+	en.external.rwMutex.RLock()
+	defer en.external.rwMutex.RUnlock()
+	targetsCopy := make(map[string]*logrus.Logger)
+	for k, v := range en.external.targets {
+		targetsCopy[k] = v
+	}
+	return targetsCopy
+}
+
+// Fetch the external target.
 func (en eventNotifier) GetExternalTarget(queueARN string) *logrus.Logger {
+	en.external.rwMutex.RLock()
+	defer en.external.rwMutex.RUnlock()
 	return en.external.targets[queueARN]
 }
 

cmd/server-startup-msg.go

@@ -101,10 +101,12 @@ func printEventNotifiers() {
 		return
 	}
 	arnMsg := colorBlue("SQS ARNs: ")
-	if len(globalEventNotifier.external.targets) == 0 {
+	// Get all configured external notification targets
+	externalTargets := globalEventNotifier.GetAllExternalTargets()
+	if len(externalTargets) == 0 {
 		arnMsg += colorBold(fmt.Sprintf(getFormatStr(len("<none>"), 1), "<none>"))
 	}
-	for queueArn := range globalEventNotifier.external.targets {
+	for queueArn := range externalTargets {
 		arnMsg += colorBold(fmt.Sprintf(getFormatStr(len(queueArn), 1), queueArn))
 	}
 	console.Println(arnMsg)