feat: Tolerate collector failures (#1769)

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>

internal/collector/mssql/mssql.go

@@ -59,6 +59,7 @@ type Config struct {
 	Port              uint16   `yaml:"port"`
 }
 
+//nolint:gochecknoglobals
 var ConfigDefaults = Config{
 	CollectorsEnabled: []string{
 		subCollectorAccessMethods,
@@ -175,7 +176,7 @@ func (c *Collector) Build(logger *slog.Logger, _ *mi.Session) error {
 
 	fileVersion, productVersion, err := c.getMSSQLServerVersion(c.config.Port)
 	if err != nil {
-		logger.Warn("Failed to get MSSQL server version",
+		logger.Warn("failed to get MSSQL server version",
 			slog.Any("err", err),
 			slog.String("collector", Name),
 		)
@@ -334,7 +335,7 @@ func (c *Collector) getMSSQLInstances() mssqlInstancesType {
 
 	k, err := registry.OpenKey(registry.LOCAL_MACHINE, regKey, registry.QUERY_VALUE)
 	if err != nil {
-		c.logger.Warn("Couldn't open registry to determine SQL instances",
+		c.logger.Warn("couldn't open registry to determine SQL instances",
 			slog.Any("err", err),
 		)
 
@@ -343,7 +344,7 @@ func (c *Collector) getMSSQLInstances() mssqlInstancesType {
 
 	defer func(key registry.Key) {
 		if err := key.Close(); err != nil {
-			c.logger.Warn("Failed to close registry key",
+			c.logger.Warn("failed to close registry key",
 				slog.Any("err", err),
 			)
 		}
@@ -351,7 +352,7 @@ func (c *Collector) getMSSQLInstances() mssqlInstancesType {
 
 	instanceNames, err := k.ReadValueNames(0)
 	if err != nil {
-		c.logger.Warn("Can't ReadSubKeyNames",
+		c.logger.Warn("can't ReadSubKeyNames",
 			slog.Any("err", err),
 		)
 
@@ -364,7 +365,7 @@ func (c *Collector) getMSSQLInstances() mssqlInstancesType {
 		}
 	}
 
-	c.logger.Debug(fmt.Sprintf("Detected MSSQL Instances: %#v\n", sqlInstances))
+	c.logger.Debug(fmt.Sprintf("detected MSSQL Instances: %#v\n", sqlInstances))
 
 	return sqlInstances
 }
@@ -401,23 +402,23 @@ func (c *Collector) collect(
 		begin := time.Now()
 		success := 1.0
 		err := collectFn(ch, sqlInstance, perfDataCollector)
-		duration := time.Since(begin).Seconds()
+		duration := time.Since(begin)
 
-		if err != nil {
+		if err != nil && !errors.Is(err, perfdata.ErrNoData) {
 			errs = append(errs, err)
 			success = 0.0
 
-			c.logger.Error(fmt.Sprintf("mssql class collector %s failed after %fs", collector, duration),
+			c.logger.Error(fmt.Sprintf("mssql class collector %s for instance %s failed after %s", collector, sqlInstance, duration),
 				slog.Any("err", err),
 			)
 		} else {
-			c.logger.Debug(fmt.Sprintf("mssql class collector %s succeeded after %fs.", collector, duration))
+			c.logger.Debug(fmt.Sprintf("mssql class collector %s for instance %s succeeded after %s.", collector, sqlInstance, duration))
 		}
 
 		ch <- prometheus.MustNewConstMetric(
 			c.mssqlScrapeDurationDesc,
 			prometheus.GaugeValue,
-			duration,
+			duration.Seconds(),
 			collector, sqlInstance,
 		)
 		ch <- prometheus.MustNewConstMetric(

internal/collector/mssql/mssql_access_methods.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -123,6 +124,7 @@ func (c *Collector) buildAccessMethods() error {
 	var err error
 
 	c.accessMethodsPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		accessMethodsAUCleanupbatchesPerSec,
 		accessMethodsAUCleanupsPerSec,
@@ -173,7 +175,7 @@ func (c *Collector) buildAccessMethods() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.accessMethodsPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Access Methods"), nil, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create AccessMethods collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create AccessMethods collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -443,7 +445,7 @@ func (c *Collector) buildAccessMethods() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectAccessMethods(ch chan<- prometheus.Metric) error {
@@ -451,6 +453,10 @@ func (c *Collector) collectAccessMethods(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectAccessMethodsInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "AccessMethods"), err)

internal/collector/mssql/mssql_availability_replica.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -54,6 +55,7 @@ func (c *Collector) buildAvailabilityReplica() error {
 	var err error
 
 	c.availabilityReplicaPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		availReplicaBytesReceivedFromReplicaPerSec,
 		availReplicaBytesSentToReplicaPerSec,
@@ -69,7 +71,7 @@ func (c *Collector) buildAvailabilityReplica() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.availabilityReplicaPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Availability Replica"), perfdata.InstancesAll, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Availability Replica collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Availability Replica collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -129,7 +131,7 @@ func (c *Collector) buildAvailabilityReplica() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectAvailabilityReplica(ch chan<- prometheus.Metric) error {
@@ -137,6 +139,10 @@ func (c *Collector) collectAvailabilityReplica(ch chan<- prometheus.Metric) erro
 }
 
 func (c *Collector) collectAvailabilityReplicaInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Availability Replica"), err)

internal/collector/mssql/mssql_buffer_manager.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -81,6 +82,7 @@ func (c *Collector) buildBufferManager() error {
 	var err error
 
 	c.bufManPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		bufManBackgroundWriterPagesPerSec,
 		bufManBufferCacheHitRatio,
@@ -110,7 +112,7 @@ func (c *Collector) buildBufferManager() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.bufManPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Buffer Manager"), nil, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Buffer Manager collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Buffer Manager collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -253,7 +255,7 @@ func (c *Collector) buildBufferManager() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectBufferManager(ch chan<- prometheus.Metric) error {
@@ -261,6 +263,10 @@ func (c *Collector) collectBufferManager(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectBufferManagerInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Buffer Manager"), err)

internal/collector/mssql/mssql_database.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -131,6 +132,7 @@ func (c *Collector) buildDatabases() error {
 	var err error
 
 	c.databasesPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		databasesActiveParallelRedoThreads,
 		databasesActiveTransactions,
@@ -185,7 +187,7 @@ func (c *Collector) buildDatabases() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.databasesPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Databases"), perfdata.InstancesAll, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Databases collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Databases collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -478,7 +480,7 @@ func (c *Collector) buildDatabases() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectDatabases(ch chan<- prometheus.Metric) error {
@@ -486,6 +488,10 @@ func (c *Collector) collectDatabases(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectDatabasesInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Databases"), err)

internal/collector/mssql/mssql_database_replica.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -83,6 +84,7 @@ func (c *Collector) buildDatabaseReplica() error {
 	var err error
 
 	c.dbReplicaPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		dbReplicaDatabaseFlowControlDelay,
 		dbReplicaDatabaseFlowControlsPerSec,
@@ -113,7 +115,7 @@ func (c *Collector) buildDatabaseReplica() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.dbReplicaPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Database Replica"), perfdata.InstancesAll, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Database Replica collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Database Replica collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -263,7 +265,7 @@ func (c *Collector) buildDatabaseReplica() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectDatabaseReplica(ch chan<- prometheus.Metric) error {
@@ -271,6 +273,10 @@ func (c *Collector) collectDatabaseReplica(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectDatabaseReplicaInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Database Replica"), err)

internal/collector/mssql/mssql_general_statistics.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -83,6 +84,7 @@ func (c *Collector) buildGeneralStatistics() error {
 	var err error
 
 	c.genStatsPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		genStatsActiveTempTables,
 		genStatsConnectionResetPerSec,
@@ -113,7 +115,7 @@ func (c *Collector) buildGeneralStatistics() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.genStatsPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "General Statistics"), nil, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create General Statistics collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create General Statistics collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -263,7 +265,7 @@ func (c *Collector) buildGeneralStatistics() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectGeneralStatistics(ch chan<- prometheus.Metric) error {
@@ -271,6 +273,10 @@ func (c *Collector) collectGeneralStatistics(ch chan<- prometheus.Metric) error
 }
 
 func (c *Collector) collectGeneralStatisticsInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "General Statistics"), err)

internal/collector/mssql/mssql_locks.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -52,6 +53,7 @@ func (c *Collector) buildLocks() error {
 	var err error
 
 	c.locksPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		locksAverageWaitTimeMS,
 		locksAverageWaitTimeMSBase,
@@ -66,7 +68,7 @@ func (c *Collector) buildLocks() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.locksPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Locks"), perfdata.InstancesAll, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Locks collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Locks collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -119,7 +121,7 @@ func (c *Collector) buildLocks() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectLocks(ch chan<- prometheus.Metric) error {
@@ -127,6 +129,10 @@ func (c *Collector) collectLocks(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectLocksInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Locks"), err)

internal/collector/mssql/mssql_memory_manager.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -75,6 +76,7 @@ func (c *Collector) buildMemoryManager() error {
 	var err error
 
 	c.memMgrPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		memMgrConnectionMemoryKB,
 		memMgrDatabaseCacheMemoryKB,
@@ -101,7 +103,7 @@ func (c *Collector) buildMemoryManager() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.memMgrPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Memory Manager"), perfdata.InstancesAll, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Locks collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Memory Manager collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -226,7 +228,7 @@ func (c *Collector) buildMemoryManager() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectMemoryManager(ch chan<- prometheus.Metric) error {
@@ -234,6 +236,10 @@ func (c *Collector) collectMemoryManager(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectMemoryManagerInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Memory Manager"), err)

internal/collector/mssql/mssql_sql_errors.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -38,6 +39,7 @@ func (c *Collector) buildSQLErrors() error {
 	var err error
 
 	c.genStatsPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		sqlErrorsErrorsPerSec,
 	}
@@ -45,7 +47,7 @@ func (c *Collector) buildSQLErrors() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.genStatsPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "SQL Errors"), perfdata.InstancesAll, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create SQL Errors collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create SQL Errors collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -57,7 +59,7 @@ func (c *Collector) buildSQLErrors() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectSQLErrors(ch chan<- prometheus.Metric) error {
@@ -65,6 +67,10 @@ func (c *Collector) collectSQLErrors(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectSQLErrorsInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "SQL Errors"), err)

internal/collector/mssql/mssql_sql_stats.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -57,6 +58,7 @@ func (c *Collector) buildSQLStats() error {
 	var err error
 
 	c.genStatsPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		sqlStatsAutoParamAttemptsPerSec,
 		sqlStatsBatchRequestsPerSec,
@@ -74,7 +76,7 @@ func (c *Collector) buildSQLStats() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.genStatsPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "SQL Statistics"), nil, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create SQL Statistics collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create SQL Statistics collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -145,7 +147,7 @@ func (c *Collector) buildSQLStats() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectSQLStats(ch chan<- prometheus.Metric) error {
@@ -153,6 +155,10 @@ func (c *Collector) collectSQLStats(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectSQLStatsInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "SQL Statistics"), err)

internal/collector/mssql/mssql_transactions.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -61,6 +62,7 @@ func (c *Collector) buildTransactions() error {
 	var err error
 
 	c.transactionsPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		transactionsFreeSpaceintempdbKB,
 		transactionsLongestTransactionRunningTime,
@@ -80,7 +82,7 @@ func (c *Collector) buildTransactions() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.transactionsPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Transactions"), nil, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Transactions collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Transactions collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -163,7 +165,7 @@ func (c *Collector) buildTransactions() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectTransactions(ch chan<- prometheus.Metric) error {
@@ -173,6 +175,10 @@ func (c *Collector) collectTransactions(ch chan<- prometheus.Metric) error {
 // Win32_PerfRawData_MSSQLSERVER_Transactions docs:
 // - https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-transactions-object
 func (c *Collector) collectTransactionsInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Transactions"), err)

internal/collector/mssql/mssql_wait_stats.go

@@ -16,6 +16,7 @@
 package mssql
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/prometheus-community/windows_exporter/internal/perfdata"
@@ -59,6 +60,7 @@ func (c *Collector) buildWaitStats() error {
 	var err error
 
 	c.waitStatsPerfDataCollectors = make(map[string]*perfdata.Collector, len(c.mssqlInstances))
+	errs := make([]error, 0, len(c.mssqlInstances))
 	counters := []string{
 		waitStatsLockWaits,
 		waitStatsMemoryGrantQueueWaits,
@@ -77,7 +79,7 @@ func (c *Collector) buildWaitStats() error {
 	for sqlInstance := range c.mssqlInstances {
 		c.waitStatsPerfDataCollectors[sqlInstance], err = perfdata.NewCollector(c.mssqlGetPerfObjectName(sqlInstance, "Wait Statistics"), perfdata.InstancesAll, counters)
 		if err != nil {
-			return fmt.Errorf("failed to create Wait Statistics collector for instance %s: %w", sqlInstance, err)
+			errs = append(errs, fmt.Errorf("failed to create Wait Statistics collector for instance %s: %w", sqlInstance, err))
 		}
 	}
 
@@ -155,7 +157,7 @@ func (c *Collector) buildWaitStats() error {
 		nil,
 	)
 
-	return nil
+	return errors.Join(errs...)
 }
 
 func (c *Collector) collectWaitStats(ch chan<- prometheus.Metric) error {
@@ -163,6 +165,10 @@ func (c *Collector) collectWaitStats(ch chan<- prometheus.Metric) error {
 }
 
 func (c *Collector) collectWaitStatsInstance(ch chan<- prometheus.Metric, sqlInstance string, perfDataCollector *perfdata.Collector) error {
+	if perfDataCollector == nil {
+		return types.ErrCollectorNotInitialized
+	}
+
 	perfData, err := perfDataCollector.Collect()
 	if err != nil {
 		return fmt.Errorf("failed to collect %s metrics: %w", c.mssqlGetPerfObjectName(sqlInstance, "Wait Statistics"), err)