PMM-10072 Filter out profiler collection

docker-compose.yml

@@ -5,7 +5,7 @@ services:
         image: ${TEST_MONGODB_IMAGE:-mongo:4.2}
         ports:
             - "${TEST_MONGODB_S1_PRIMARY_PORT:-17001}:27017"
-        command: mongod --replSet rs1 --shardsvr --port 27017  --oplogSize 16
+        command: mongod --replSet rs1 --shardsvr --port 27017  --oplogSize 16 --profile 2
         links:
             - mongo-1-2:mongo-1-2
             - mongo-1-3:mongo-1-3
@@ -15,14 +15,14 @@ services:
         image: ${TEST_MONGODB_IMAGE:-mongo:4.2}
         ports:
             - "${TEST_MONGODB_S1_SECONDARY1_PORT:-17002}:27017"
-        command: mongod --replSet rs1 --shardsvr --port 27017  --oplogSize 16
+        command: mongod --replSet rs1 --shardsvr --port 27017  --oplogSize 16 --profile 2
 
     mongo-1-3:
         container_name: "mongo-1-3"
         image: ${TEST_MONGODB_IMAGE:-mongo:4.2}
         ports:
             - "${TEST_MONGODB_S1_SECONDARY2_PORT:-17003}:27017"
-        command: mongod --replSet rs1 --shardsvr --port 27017  --oplogSize 16
+        command: mongod --replSet rs1 --shardsvr --port 27017  --oplogSize 16 --profile 2
 
     mongo-1-arbiter:
         container_name: "mongo-1-arbiter"

exporter/common.go

@@ -62,7 +62,9 @@ func listCollections(ctx context.Context, client *mongo.Client, database string,
 		return nil, errors.Wrap(err, "cannot get the list of collections for discovery")
 	}
 
-	return collections, nil
+	filteredCollections := filterSystemCollections(collections)
+
+	return filteredCollections, nil
 }
 
 // databases returns the list of databases matching the filters.
@@ -200,6 +202,22 @@ func listAllCollections(ctx context.Context, client *mongo.Client, filterInNames
 	return namespaces, nil
 }
 
+func filterSystemCollections(cols []string) []string {
+	systemCollections := map[string]bool{
+		"system.profile": true,
+	}
+
+	filtered := make([]string, 0, len(cols))
+	for _, col := range cols {
+		if systemCollections[col] {
+			continue
+		}
+		filtered = append(filtered, col)
+	}
+
+	return filtered
+}
+
 func nonSystemCollectionsCount(ctx context.Context, client *mongo.Client, includeNamespaces []string, filterInCollections []string) (int, error) {
 	databases, err := databases(ctx, client, includeNamespaces, systemDBs)
 	if err != nil {

exporter/dbstats_collector_test.go

@@ -17,58 +17,41 @@ package exporter
 
 import (
 	"context"
-	"fmt"
 	"strings"
 	"testing"
 	"time"
 
 	"github.com/prometheus/client_golang/prometheus/testutil"
 	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"
-	"go.mongodb.org/mongo-driver/bson"
 
 	"github.com/percona/mongodb_exporter/internal/tu"
 )
 
-const (
-	dbName = "testdb"
-)
-
 func TestDBStatsCollector(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
 	defer cancel()
 
 	client := tu.DefaultTestClient(ctx, t)
-
-	database := client.Database(dbName)
-	database.Drop(ctx) //nolint
-
-	defer func() {
-		err := database.Drop(ctx)
-		assert.NoError(t, err)
-	}()
-
-	for i := 0; i < 3; i++ {
-		coll := fmt.Sprintf("testcol_%02d", i)
-		for j := 0; j < 10; j++ {
-			_, err := database.Collection(coll).InsertOne(ctx, bson.M{"f1": j, "f2": "2"})
-			assert.NoError(t, err)
-		}
-	}
+	setupDB(ctx, t, client)
+	defer cleanupDB(ctx, client)
 
 	ti := labelsGetterMock{}
 
-	c := newDBStatsCollector(ctx, client, logrus.New(), false, ti, []string{dbName}, false)
+	c := newDBStatsCollector(ctx, client, logrus.New(), false, ti, testDBs, false)
 	expected := strings.NewReader(`
 	# HELP mongodb_dbstats_collections dbstats.
 	# TYPE mongodb_dbstats_collections untyped
-	mongodb_dbstats_collections{database="testdb"} 3
+	mongodb_dbstats_collections{database="testdb01"} 5
+	mongodb_dbstats_collections{database="testdb02"} 5
 	# HELP mongodb_dbstats_indexes dbstats.
 	# TYPE mongodb_dbstats_indexes untyped
-	mongodb_dbstats_indexes{database="testdb"} 3
+	mongodb_dbstats_indexes{database="testdb01"} 4
+	mongodb_dbstats_indexes{database="testdb02"} 4
 	# HELP mongodb_dbstats_objects dbstats.
 	# TYPE mongodb_dbstats_objects untyped
-	mongodb_dbstats_objects{database="testdb"} 30` + "\n")
+	mongodb_dbstats_objects{database="testdb01"} 80
+	mongodb_dbstats_objects{database="testdb02"} 80` + "\n")
 
 	// Only look at metrics created by our activity
 	filters := []string{