converge clusterRead health into cluster health (#19063)

cmd/healthcheck-handler.go

@@ -81,12 +81,28 @@ func ClusterReadCheckHandler(w http.ResponseWriter, r *http.Request) {
 	ctx, cancel := context.WithTimeout(ctx, globalAPIConfig.getClusterDeadline())
 	defer cancel()
 
-	result := objLayer.ReadHealth(ctx)
-	if !result {
-		writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
+	opts := HealthOptions{
+		Maintenance:    r.Form.Get("maintenance") == "true",
+		DeploymentType: r.Form.Get("deployment-type"),
+	}
+	result := objLayer.Health(ctx, opts)
+	w.Header().Set(xhttp.MinIOReadQuorum, strconv.Itoa(result.ReadQuorum))
+	w.Header().Set(xhttp.MinIOStorageClassDefaults, strconv.FormatBool(result.UsingDefaults))
+	// return how many drives are being healed if any
+	if result.HealingDrives > 0 {
+		w.Header().Set(xhttp.MinIOHealingDrives, strconv.Itoa(result.HealingDrives))
+	}
+	if !result.HealthyRead {
+		// As a maintenance call we are purposefully asked to be taken
+		// down, this is for orchestrators to know if we can safely
+		// take this server down, return appropriate error.
+		if opts.Maintenance {
+			writeResponse(w, http.StatusPreconditionFailed, nil, mimeNone)
+		} else {
+			writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
+		}
 		return
 	}
-
 	writeResponse(w, http.StatusOK, nil, mimeNone)
 }