From 5dd6a44910994714b0ad379acb1187c17b72b31f Mon Sep 17 00:00:00 2001
From: idoko <okokomichaels@outlook.com>
Date: Mon, 27 May 2024 08:56:23 +0100
Subject: [PATCH] split metrics collection

---
 exporter/diagnostic_data_collector.go | 22 +++++++++++++++++++---
 exporter/v1_compatibility.go          | 25 +++++--------------------
 2 files changed, 24 insertions(+), 23 deletions(-)

diff --git a/exporter/diagnostic_data_collector.go b/exporter/diagnostic_data_collector.go
index e4c48ee60..8666838bd 100644
--- a/exporter/diagnostic_data_collector.go
+++ b/exporter/diagnostic_data_collector.go
@@ -81,6 +81,7 @@ func (d *diagnosticDataCollector) collect(ch chan<- prometheus.Metric) {
 	} else {
 		if err := res.Decode(&m); err != nil {
 			logger.Errorf("cannot run getDiagnosticData: %s", err)
+			return
 		}
 
 		if m == nil || m["data"] == nil {
@@ -106,13 +107,28 @@ func (d *diagnosticDataCollector) collect(ch chan<- prometheus.Metric) {
 		} else if securityMetric != nil {
 			metrics = append(metrics, securityMetric)
 		}
+
+		if d.compatibleMode {
+			metrics = append(metrics, specialMetrics(d.ctx, client, m, nodeType, logger)...)
+
+			if cem, err := cacheEvictedTotalMetric(m); err == nil {
+				metrics = append(metrics, cem)
+			}
+		}
 	}
 
 	if d.compatibleMode {
-		metrics = append(metrics, specialMetrics(d.ctx, client, m, logger)...)
+		buildInfo, err := retrieveMongoDBBuildInfo(d.ctx, client, logger)
+		if err != nil {
+			logger.Errorf("cannot retrieve MongoDB buildInfo: %s", err)
+		}
+
+		metrics = append(metrics, serverVersion(buildInfo))
 
-		if cem, err := cacheEvictedTotalMetric(m); err == nil {
-			metrics = append(metrics, cem)
+		if nodeType == typeArbiter {
+			if hm := arbiterMetrics(d.ctx, client, logger); hm != nil {
+				metrics = append(metrics, hm...)
+			}
 		}
 
 		if nodeType == typeMongos {
diff --git a/exporter/v1_compatibility.go b/exporter/v1_compatibility.go
index 1c4b81f4d..750f68ecd 100644
--- a/exporter/v1_compatibility.go
+++ b/exporter/v1_compatibility.go
@@ -782,7 +782,7 @@ func specialMetricDefinitions() []specialMetric {
 	}
 }
 
-func specialMetrics(ctx context.Context, client *mongo.Client, m bson.M, l *logrus.Logger) []prometheus.Metric {
+func specialMetrics(ctx context.Context, client *mongo.Client, m bson.M, nodeType mongoDBNodeType, l *logrus.Logger) []prometheus.Metric {
 	metrics := make([]prometheus.Metric, 0)
 
 	for _, def := range specialMetricDefinitions() {
@@ -802,30 +802,15 @@ func specialMetrics(ctx context.Context, client *mongo.Client, m bson.M, l *logr
 		metrics = append(metrics, metric)
 	}
 
-	buildInfo, err := retrieveMongoDBBuildInfo(ctx, client, l)
-	if err != nil {
-		l.Errorf("cannot retrieve MongoDB buildInfo: %s", err)
-	}
-
-	nodeType, err := getNodeType(ctx, client)
-	if err != nil {
-		l.WithFields(logrus.Fields{
-			"component": "diagnosticDataCollector",
-		}).Errorf("Cannot get node type: %s", err)
-	}
-
 	if nodeType == typeMongod || nodeType == typeArbiter {
-		if engine, err := storageEngine(m); err == nil {
+		if engine, err := storageEngine(m); err != nil {
+			l.Errorf("cannot retrieve engine type: %s", err)
+		} else {
 			metrics = append(metrics, engine)
 		}
 	}
-	metrics = append(metrics, serverVersion(buildInfo))
 
-	if nodeType == typeArbiter {
-		if hm := arbiterMetrics(ctx, client, l); hm != nil {
-			metrics = append(metrics, hm...)
-		}
-	} else {
+	if nodeType != typeArbiter {
 		metrics = append(metrics, myState(ctx, client))
 		if rm := replSetMetrics(m); rm != nil {
 			metrics = append(metrics, rm...)