coroot · def · Sep 19, 2025 · Sep 19, 2025
diff --git a/auditor/auditor.go b/auditor/auditor.go
@@ -66,6 +66,7 @@ func Audit(w *model.World, p *db.Project, generateDetailedReportFor *model.Appli
 		stages.stage("jvm", a.jvm)
 		stages.stage("dotnet", a.dotnet)
 		stages.stage("python", a.python)
+		stages.stage("nodejs", a.nodejs)
 		stages.stage("logs", a.logs)
 		stages.stage("deployments", a.deployments)
 

diff --git a/auditor/nodejs.go b/auditor/nodejs.go
@@ -0,0 +1,26 @@
+package auditor
+
+import (
+	"github.com/coroot/coroot/model"
+)
+
+func (a *appAuditor) nodejs() {
+	if !a.app.IsNodejs() {
+		return
+	}
+
+	report := a.addReport(model.AuditReportNodejs)
+	check := report.CreateCheck(model.Checks.NodejsEventLoopBlockedTime)
+	chart := report.GetOrCreateChart("Node.js event loop blocked time, seconds/second", nil)
+	for _, i := range a.app.Instances {
+		if i.Nodejs == nil {
+			continue
+		}
+		if i.Nodejs.EventLoopBlockedTime.Last() > check.Threshold {
+			check.AddItem(i.Name)
+		}
+		if chart != nil {
+			chart.AddSeries(i.Name, i.Nodejs.EventLoopBlockedTime)
+		}
+	}
+}
diff --git a/constructor/constructor.go b/constructor/constructor.go
@@ -110,6 +110,7 @@ func (c *Constructor) LoadWorld(ctx context.Context, from, to timeseries.Time, s
 	prof.stage("load_jvm", func() { c.loadJVM(metrics, containers) })
 	prof.stage("load_dotnet", func() { c.loadDotNet(metrics, containers) })
 	prof.stage("load_python", func() { c.loadPython(metrics, containers) })
+	prof.stage("load_nodejs", func() { c.loadNodejs(metrics, containers) })
 	prof.stage("enrich_instances", func() { enrichInstances(w, metrics, rdsInstancesById, ecInstancesById) })
 	prof.stage("calc_app_categories", func() { c.calcApplicationCategories(w) })
 	prof.stage("group_custom_applications", func() { c.groupCustomApplications(w) })

diff --git a/constructor/nodejs.go b/constructor/nodejs.go
@@ -0,0 +1,24 @@
+package constructor
+
+import (
+	"github.com/coroot/coroot/model"
+	"github.com/coroot/coroot/timeseries"
+)
+
+func (c *Constructor) loadNodejs(metrics map[string][]*model.MetricValues, containers containerCache) {
+	load := func(queryName string, f func(nodejs *model.Nodejs, metric *model.MetricValues)) {
+		for _, metric := range metrics[queryName] {
+			v := containers[metric.NodeContainerId]
+			if v.instance == nil {
+				continue
+			}
+			if v.instance.Nodejs == nil {
+				v.instance.Nodejs = &model.Nodejs{}
+			}
+			f(v.instance.Nodejs, metric)
+		}
+	}
+	load("container_nodejs_event_loop_blocked_time_seconds", func(nodejs *model.Nodejs, metric *model.MetricValues) {
+		nodejs.EventLoopBlockedTime = merge(nodejs.EventLoopBlockedTime, metric.Values, timeseries.Any)
+	})
+}
diff --git a/constructor/queries.go b/constructor/queries.go
@@ -371,6 +371,7 @@ var QUERIES = []Query{
 	qDotNet("container_dotnet_thread_pool_size", `container_dotnet_thread_pool_size`),
 
 	Q("container_python_thread_lock_wait_time_seconds", `rate(container_python_thread_lock_wait_time_seconds[$RANGE])`),
+	Q("container_nodejs_event_loop_blocked_time_seconds", `rate(container_nodejs_event_loop_blocked_time_seconds_total[$RANGE])`),
 }
 
 var RecordingRules = map[string]func(db *db.DB, p *db.Project, w *model.World) []*model.MetricValues{

diff --git a/model/application.go b/model/application.go
@@ -223,6 +223,15 @@ func (app *Application) IsPython() bool {
 	return false
 }
 
+func (app *Application) IsNodejs() bool {
+	for _, i := range app.Instances {
+		if i.Nodejs != nil {
+			return true
+		}
+	}
+	return false
+}
+
 func (app *Application) IsStandalone() bool {
 	for _, d := range app.Downstreams {
 		if d.Application != d.RemoteApplication {

diff --git a/model/application_types.go b/model/application_types.go
@@ -118,6 +118,8 @@ func (at ApplicationType) AuditReport() AuditReportName {
 		return AuditReportDotNet
 	case ApplicationTypePython:
 		return AuditReportPython
+	case ApplicationTypeNodeJS:
+		return AuditReportNodejs
 	}
 	return ""
 }

diff --git a/model/audit_report.go b/model/audit_report.go
@@ -28,6 +28,7 @@ const (
 	AuditReportJvm         AuditReportName = "JVM"
 	AuditReportDotNet      AuditReportName = ".NET"
 	AuditReportPython      AuditReportName = "Python"
+	AuditReportNodejs      AuditReportName = "Node.js"
 	AuditReportNode        AuditReportName = "Node"
 	AuditReportDeployments AuditReportName = "Deployments"
 	AuditReportProfiling   AuditReportName = "Profiling"

diff --git a/model/check.go b/model/check.go
@@ -62,41 +62,42 @@ type CheckConfig struct {
 var Checks = struct {
 	index map[CheckId]*CheckConfig
 
-	SLOAvailability        CheckConfig
-	SLOLatency             CheckConfig
-	CPUNode                CheckConfig
-	CPUContainer           CheckConfig
-	MemoryOOM              CheckConfig
-	MemoryLeakPercent      CheckConfig
-	StorageSpace           CheckConfig
-	StorageIOLoad          CheckConfig
-	NetworkRTT             CheckConfig
-	NetworkConnectivity    CheckConfig
-	NetworkTCPConnections  CheckConfig
-	InstanceAvailability   CheckConfig
-	DeploymentStatus       CheckConfig
-	InstanceRestarts       CheckConfig
-	RedisAvailability      CheckConfig
-	RedisLatency           CheckConfig
-	MongodbAvailability    CheckConfig
-	MongodbReplicationLag  CheckConfig
-	MemcachedAvailability  CheckConfig
-	PostgresAvailability   CheckConfig
-	PostgresLatency        CheckConfig
-	PostgresReplicationLag CheckConfig
-	PostgresConnections    CheckConfig
-	LogErrors              CheckConfig
-	JvmAvailability        CheckConfig
-	JvmSafepointTime       CheckConfig
-	DotNetAvailability     CheckConfig
-	PythonGILWaitingTime   CheckConfig
-	DnsLatency             CheckConfig
-	DnsServerErrors        CheckConfig
-	DnsNxdomainErrors      CheckConfig
-	MysqlAvailability      CheckConfig
-	MysqlReplicationStatus CheckConfig
-	MysqlReplicationLag    CheckConfig
-	MysqlConnections       CheckConfig
+	SLOAvailability            CheckConfig
+	SLOLatency                 CheckConfig
+	CPUNode                    CheckConfig
+	CPUContainer               CheckConfig
+	MemoryOOM                  CheckConfig
+	MemoryLeakPercent          CheckConfig
+	StorageSpace               CheckConfig
+	StorageIOLoad              CheckConfig
+	NetworkRTT                 CheckConfig
+	NetworkConnectivity        CheckConfig
+	NetworkTCPConnections      CheckConfig
+	InstanceAvailability       CheckConfig
+	DeploymentStatus           CheckConfig
+	InstanceRestarts           CheckConfig
+	RedisAvailability          CheckConfig
+	RedisLatency               CheckConfig
+	MongodbAvailability        CheckConfig
+	MongodbReplicationLag      CheckConfig
+	MemcachedAvailability      CheckConfig
+	PostgresAvailability       CheckConfig
+	PostgresLatency            CheckConfig
+	PostgresReplicationLag     CheckConfig
+	PostgresConnections        CheckConfig
+	LogErrors                  CheckConfig
+	JvmAvailability            CheckConfig
+	JvmSafepointTime           CheckConfig
+	DotNetAvailability         CheckConfig
+	PythonGILWaitingTime       CheckConfig
+	NodejsEventLoopBlockedTime CheckConfig
+	DnsLatency                 CheckConfig
+	DnsServerErrors            CheckConfig
+	DnsNxdomainErrors          CheckConfig
+	MysqlAvailability          CheckConfig
+	MysqlReplicationStatus     CheckConfig
+	MysqlReplicationLag        CheckConfig
+	MysqlConnections           CheckConfig
 }{
 	index: map[CheckId]*CheckConfig{},
 
@@ -312,6 +313,14 @@ var Checks = struct {
 		ConditionFormatTemplate: "the time Python threads have been waiting for acquiring the GIL (Global Interpreter Lock) > <threshold>",
 		Unit:                    CheckUnitSecond,
 	},
+	NodejsEventLoopBlockedTime: CheckConfig{
+		Type:                    CheckTypeItemBased,
+		Title:                   "Node.js event loop blocked time",
+		DefaultThreshold:        0.7,
+		MessageTemplate:         `high Node.js event loop blocked times on {{.Items "Node.js instance"}}`,
+		ConditionFormatTemplate: "the time Node.js event loop executes blocking code > <threshold>",
+		Unit:                    CheckUnitSecond,
+	},
 	DnsLatency: CheckConfig{
 		Type:                    CheckTypeValueBased,
 		Title:                   "DNS latency",

diff --git a/model/instance.go b/model/instance.go
@@ -39,6 +39,7 @@ type Instance struct {
 	Jvms   map[string]*Jvm
 	DotNet map[string]*DotNet
 	Python *Python
+	Nodejs *Nodejs
 
 	Volumes []*Volume
 

diff --git a/model/nodejs.go b/model/nodejs.go
@@ -0,0 +1,7 @@
+package model
+
+import "github.com/coroot/coroot/timeseries"
+
+type Nodejs struct {
+	EventLoopBlockedTime *timeseries.TimeSeries
+}