Merge pull request #263 from martinlindhe/linting

Add linting

Makefile

@@ -1,14 +1,17 @@
 export GOOS=windows
 
-fmt:
-	gofmt -l -w -s .
-
 build:
 	promu build -v
 
 test:
 	go test -v ./...
 
+lint:
+	gometalinter --vendor --config gometalinter.config ./...
+
+fmt:
+	gofmt -l -w -s .
+
 crossbuild:
 	# The prometheus/golang-builder image for promu crossbuild doesn't exist
 	# on Windows, so for now, we'll just build twice

appveyor.yml

@@ -12,11 +12,15 @@ clone_folder: c:\gopath\src\github.com\martinlindhe\wmi_exporter
 install:
   - set PATH=%GOPATH%\bin;%PATH%
   - go get -u github.com/prometheus/promu
+  - go get -u github.com/alecthomas/gometalinter && gometalinter --install
   - choco install gitversion.portable make -y
 
 test_script:
   - make test
 
+after_test:
+  - make lint
+
 build_script:
   - ps: |
       $ErrorActionPreference = "Stop"

collector/ad.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_DirectoryServices_DirectoryServices
-// Partial docs: https://msdn.microsoft.com/en-us/library/ms803980.aspx
-
 // +build windows
 
 package collector
@@ -465,6 +462,8 @@ func (c *ADCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_PerfRawData_DirectoryServices_DirectoryServices docs:
+// - https://msdn.microsoft.com/en-us/library/ms803980.aspx
 type Win32_PerfRawData_DirectoryServices_DirectoryServices struct {
 	Name string
 
@@ -488,8 +487,8 @@ type Win32_PerfRawData_DirectoryServices_DirectoryServices struct {
 	DatabasemodifysPersec                                            uint32
 	DatabaserecyclesPersec                                           uint32
 	DigestBindsPersec                                                uint32
-	DRAHighestUSNCommittedHighpart                                   uint32
+	DRAHighestUSNCommittedHighpart                                   uint64
-	DRAHighestUSNCommittedLowpart                                    uint32
+	DRAHighestUSNCommittedLowpart                                    uint64
 	DRAHighestUSNIssuedHighpart                                      uint64
 	DRAHighestUSNIssuedLowpart                                       uint64
 	DRAInboundBytesCompressedBetweenSitesAfterCompressionPersec      uint32

collector/cpu.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_PerfOS_Processor
-// https://msdn.microsoft.com/en-us/library/aa394317(v=vs.90).aspx - Win32_PerfRawData_PerfOS_Processor class
-
 // +build windows
 
 package collector
@@ -25,6 +22,7 @@ type CPUCollector struct {
 	DPCsTotal          *prometheus.Desc
 }
 
+// NewCPUCollector constructs a new CPUCollector
 func NewCPUCollector() (Collector, error) {
 	const subsystem = "cpu"
 	return &CPUCollector{
@@ -66,6 +64,8 @@ func (c *CPUCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_PerfRawData_PerfOS_Processor docs:
+// - https://msdn.microsoft.com/en-us/library/aa394317(v=vs.90).aspx
 type Win32_PerfRawData_PerfOS_Processor struct {
 	Name                  string
 	C1TransitionsPersec   uint64

collector/cs.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_ComputerSystem
-// https://msdn.microsoft.com/en-us/library/aa394102 - Win32_ComputerSystem class
-
 // +build windows
 
 package collector
@@ -53,6 +50,8 @@ func (c *CSCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_ComputerSystem docs:
+// - https://msdn.microsoft.com/en-us/library/aa394102
 type Win32_ComputerSystem struct {
 	NumberOfLogicalProcessors uint32
 	TotalPhysicalMemory       uint64

collector/dns.go

@@ -1,7 +1,3 @@
-// returns data points from Win32_PerfRawData_DNS_DNS
-// https://msdn.microsoft.com/en-us/library/ms803992.aspx?f=255&MSPPError=-2147217396
-// https://technet.microsoft.com/en-us/library/cc977686.aspx
-
 // +build windows
 
 package collector
@@ -193,6 +189,9 @@ func (c *DNSCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_PerfRawData_DNS_DNS docs:
+// - https://msdn.microsoft.com/en-us/library/ms803992.aspx?f=255&MSPPError=-2147217396
+// - https://technet.microsoft.com/en-us/library/cc977686.aspx
 type Win32_PerfRawData_DNS_DNS struct {
 	AXFRRequestReceived            uint32
 	AXFRRequestSent                uint32

collector/iis.go

@@ -1,9 +1,3 @@
-// returns data points from the following classes:
-// - Win32_PerfRawData_W3SVC_WebService
-// - Win32_PerfRawData_APPPOOLCountersProvider_APPPOOLWAS
-// - Win32_PerfRawData_W3SVCW3WPCounterProvider_W3SVCW3WP
-// - Win32_PerfRawData_W3SVC_WebServiceCache
-
 // +build windows
 
 package collector
@@ -36,7 +30,12 @@ func getIISVersion() simple_version {
 		log.Warn("Couldn't open registry to determine IIS version:", err)
 		return simple_version{}
 	}
-	defer k.Close()
+	defer func() {
+		err = k.Close()
+		if err != nil {
+			log.Warnf("Failed to close registry key: %v", err)
+		}
+	}()
 
 	major, _, err := k.GetIntegerValue("MajorVersion")
 	if err != nil {
@@ -808,8 +807,8 @@ func NewIISCollector() (Collector, error) {
 			nil,
 		),
 
-		appWhitelistPattern: regexp.MustCompile(fmt.Sprintf("^(?:%s)$", *siteWhitelist)),
+		appWhitelistPattern: regexp.MustCompile(fmt.Sprintf("^(?:%s)$", *appWhitelist)),
-		appBlacklistPattern: regexp.MustCompile(fmt.Sprintf("^(?:%s)$", *siteBlacklist)),
+		appBlacklistPattern: regexp.MustCompile(fmt.Sprintf("^(?:%s)$", *appBlacklist)),
 	}
 
 	buildIIS.iis_version = getIISVersion()
@@ -986,7 +985,7 @@ type Win32_PerfRawData_W3SVC_WebServiceCache struct {
 	URICacheMisses                 uint32
 }
 
-var ApplicationStates = map[uint32]string{
+var applicationStates = map[uint32]string{
 	1: "Uninitialized",
 	2: "Initialized",
 	3: "Running",
@@ -1267,7 +1266,7 @@ func (c *IISCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, e
 		}
 
 		// Guages
-		for key, label := range ApplicationStates {
+		for key, label := range applicationStates {
 			isCurrentState := 0.0
 			if key == app.CurrentApplicationPoolState {
 				isCurrentState = 1.0

collector/logical_disk.go

@@ -1,7 +1,3 @@
-// returns data points from Win32_PerfRawData_PerfDisk_LogicalDisk
-// https://msdn.microsoft.com/en-us/windows/hardware/aa394307(v=vs.71) - Win32_PerfRawData_PerfDisk_LogicalDisk class
-// https://msdn.microsoft.com/en-us/library/ms803973.aspx - LogicalDisk object reference
-
 // +build windows
 
 package collector
@@ -146,6 +142,9 @@ func (c *LogicalDiskCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_PerfRawData_PerfDisk_LogicalDisk docs:
+// - https://msdn.microsoft.com/en-us/windows/hardware/aa394307(v=vs.71) - Win32_PerfRawData_PerfDisk_LogicalDisk class
+// - https://msdn.microsoft.com/en-us/library/ms803973.aspx - LogicalDisk object reference
 type Win32_PerfRawData_PerfDisk_LogicalDisk struct {
 	Name                   string
 	CurrentDiskQueueLength uint32

collector/msmq.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_MSMQ_MSMQQueue
-// <add link to documentation here> - Win32_PerfRawData_MSMQ_MSMQQueue class
-
 // +build windows
 
 package collector

collector/mssql.go

@@ -1,23 +1,3 @@
-// returns data points from the following classes:
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerAccessMethods
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-access-methods-object
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerAvailabilityReplica
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-availability-replica
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerBufferManager
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-buffer-manager-object
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerDatabaseReplica
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-database-replica
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerDatabases
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-databases-object?view=sql-server-2017
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerGeneralStatistics
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-general-statistics-object
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerLocks
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-locks-object
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerMemoryManager
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-memory-manager-object
-// - Win32_PerfRawData_MSSQLSERVER_SQLServerSQLStatistics
-//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-sql-statistics-object
-
 // +build windows
 
 package collector
@@ -64,7 +44,12 @@ func getMSSQLInstances() mssqlInstancesType {
 		log.Warn("Couldn't open registry to determine SQL instances:", err)
 		return sqlDefaultInstance
 	}
-	defer k.Close()
+	defer func() {
+		err = k.Close()
+		if err != nil {
+			log.Warnf("Failed to close registry key: %v", err)
+		}
+	}()
 
 	instanceNames, err := k.ReadValueNames(0)
 	if err != nil {
@@ -383,7 +368,7 @@ func NewMSSQLCollector() (Collector, error) {
 
 	const subsystem = "mssql"
 
-	MSSQLCollector := MSSQLCollector{
+	mssqlCollector := MSSQLCollector{
 		// meta
 		mssqlScrapeDurationDesc: prometheus.NewDesc(
 			prometheus.BuildFQName(Namespace, subsystem, "collector_duration_seconds"),
@@ -1655,17 +1640,17 @@ func NewMSSQLCollector() (Collector, error) {
 		mssqlInstances: getMSSQLInstances(),
 	}
 
-	MSSQLCollector.mssqlCollectors = MSSQLCollector.getMSSQLCollectors()
+	mssqlCollector.mssqlCollectors = mssqlCollector.getMSSQLCollectors()
 
 	if *mssqlPrintCollectors {
 		fmt.Printf("Available SQLServer Classes:\n")
-		for name := range MSSQLCollector.mssqlCollectors {
+		for name := range mssqlCollector.mssqlCollectors {
 			fmt.Printf(" - %s\n", name)
 		}
 		os.Exit(0)
 	}
 
-	return &MSSQLCollector, nil
+	return &mssqlCollector, nil
 }
 
 type mssqlCollectorFunc func(ch chan<- prometheus.Metric, sqlInstance string) (*prometheus.Desc, error)
@@ -1723,6 +1708,9 @@ func (c *MSSQLCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// win32PerfRawDataSQLServerAccessMethods docs:
+// - Win32_PerfRawData_MSSQLSERVER_SQLServerAccessMethods
+//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-access-methods-object
 type win32PerfRawDataSQLServerAccessMethods struct {
 	AUcleanupbatchesPersec        uint64
 	AUcleanupsPersec              uint64
@@ -2087,6 +2075,8 @@ func (c *MSSQLCollector) collectAccessMethods(ch chan<- prometheus.Metric, sqlIn
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerAvailabilityReplica docs:
+//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-availability-replica
 type win32PerfRawDataSQLServerAvailabilityReplica struct {
 	Name                           string
 	BytesReceivedfromReplicaPersec uint64
@@ -2179,6 +2169,8 @@ func (c *MSSQLCollector) collectAvailabilityReplica(ch chan<- prometheus.Metric,
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerBufferManager docs:
+//   https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-buffer-manager-object
 type win32PerfRawDataSQLServerBufferManager struct {
 	BackgroundwriterpagesPersec   uint64
 	Buffercachehitratio           uint64
@@ -2376,6 +2368,8 @@ func (c *MSSQLCollector) collectBufferManager(ch chan<- prometheus.Metric, sqlIn
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerDatabaseReplica docs:
+// - https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-database-replica
 type win32PerfRawDataSQLServerDatabaseReplica struct {
 	Name                            string
 	DatabaseFlowControlDelay        uint64
@@ -2588,6 +2582,8 @@ func (c *MSSQLCollector) collectDatabaseReplica(ch chan<- prometheus.Metric, sql
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerDatabases docs:
+// - https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-databases-object?view=sql-server-2017
 type win32PerfRawDataSQLServerDatabases struct {
 	Name                             string
 	ActiveTransactions               uint64
@@ -2976,6 +2972,8 @@ func (c *MSSQLCollector) collectDatabases(ch chan<- prometheus.Metric, sqlInstan
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerGeneralStatistics docs:
+// - https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-general-statistics-object
 type win32PerfRawDataSQLServerGeneralStatistics struct {
 	ActiveTempTables              uint64
 	ConnectionResetPersec         uint64
@@ -3188,6 +3186,8 @@ func (c *MSSQLCollector) collectGeneralStatistics(ch chan<- prometheus.Metric, s
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerLocks docs:
+// - https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-locks-object
 type win32PerfRawDataSQLServerLocks struct {
 	Name                       string
 	AverageWaitTimems          uint64
@@ -3264,6 +3264,8 @@ func (c *MSSQLCollector) collectLocks(ch chan<- prometheus.Metric, sqlInstance s
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerMemoryManager docs:
+// - https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-memory-manager-object
 type win32PerfRawDataSQLServerMemoryManager struct {
 	ConnectionMemoryKB       uint64
 	DatabaseCacheMemoryKB    uint64
@@ -3445,6 +3447,8 @@ func (c *MSSQLCollector) collectMemoryManager(ch chan<- prometheus.Metric, sqlIn
 	return nil, nil
 }
 
+// Win32_PerfRawData_MSSQLSERVER_SQLServerSQLStatistics docs:
+// - https://docs.microsoft.com/en-us/sql/relational-databases/performance-monitor/sql-server-sql-statistics-object
 type win32PerfRawDataSQLServerSQLStatistics struct {
 	AutoParamAttemptsPersec       uint64
 	BatchRequestsPersec           uint64

collector/net.go

@@ -1,9 +1,3 @@
-// returns data points from Win32_PerfRawData_Tcpip_NetworkInterface
-
-// https://technet.microsoft.com/en-us/security/aa394340(v=vs.80) (Win32_PerfRawData_Tcpip_NetworkInterface class)
-// https://msdn.microsoft.com/en-us/library/aa394216 (Win32_NetworkAdapter class)
-// https://msdn.microsoft.com/en-us/library/aa394353 (Win32_PnPEntity class)
-
 // +build windows
 
 package collector
@@ -152,6 +146,8 @@ func mangleNetworkName(name string) string {
 	return nicNameToUnderscore.ReplaceAllString(name, "_")
 }
 
+// Win32_PerfRawData_Tcpip_NetworkInterface docs:
+// - https://technet.microsoft.com/en-us/security/aa394340(v=vs.80)
 type Win32_PerfRawData_Tcpip_NetworkInterface struct {
 	BytesReceivedPerSec      uint64
 	BytesSentPerSec          uint64

collector/netframework_clrexceptions.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRExceptions
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRExceptions class
-
 // +build windows
 
 package collector

collector/netframework_clrinterop.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRInterop
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRInterop class
-
 // +build windows
 
 package collector

collector/netframework_clrjit.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRJit
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRJit class
-
 // +build windows
 
 package collector

collector/netframework_clrloading.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRLoading
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRLoading class
-
 // +build windows
 
 package collector

collector/netframework_clrlocksandthreads.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRLocksAndThreads
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRLocksAndThreads class
-
 // +build windows
 
 package collector

collector/netframework_clrmemory.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRMemory
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRMemory class
-
 // +build windows
 
 package collector

collector/netframework_clrremoting.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRRemoting
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRRemoting class
-
 // +build windows
 
 package collector

collector/netframework_clrsecurity.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_NETFramework_NETCLRSecurity
-// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRSecurity class
-
 // +build windows
 
 package collector

collector/os.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_OperatingSystem
-// https://msdn.microsoft.com/en-us/library/aa394239 - Win32_OperatingSystem class
-
 // +build windows
 
 package collector
@@ -124,6 +121,8 @@ func (c *OSCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_OperatingSystem docs:
+// - https://msdn.microsoft.com/en-us/library/aa394239 - Win32_OperatingSystem class
 type Win32_OperatingSystem struct {
 	FreePhysicalMemory      uint64
 	FreeSpaceInPagingFiles  uint64

collector/process.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_PerfProc_Process
-// https://msdn.microsoft.com/en-us/library/aa394323(v=vs.85).aspx - Win32_PerfRawData_PerfProc_Process class
-
 // +build windows
 
 package collector
@@ -146,6 +143,8 @@ func (c *ProcessCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_PerfRawData_PerfProc_Process docs:
+// - https://msdn.microsoft.com/en-us/library/aa394323(v=vs.85).aspx
 type Win32_PerfRawData_PerfProc_Process struct {
 	Name                    string
 	CreatingProcessID       uint32
@@ -195,7 +194,7 @@ func (c *ProcessCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Des
 	var dst_wp []WorkerProcess
 	q_wp := queryAll(&dst_wp)
 	if err := wmi.QueryNamespace(q_wp, &dst_wp, "root\\WebAdministration"); err != nil {
-		log.Warnf("failed querying worker processes: %s", err)
+		log.Debugf("Could not query WebAdministration namespace for IIS worker processes: %v. Skipping", err)
 	}
 
 	for _, process := range dst {

collector/service.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_Service
-// https://msdn.microsoft.com/en-us/library/aa394418(v=vs.85).aspx - Win32_Service class
-
 // +build windows
 
 package collector
@@ -75,6 +72,8 @@ func (c *serviceCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_Service docs:
+// - https://msdn.microsoft.com/en-us/library/aa394418(v=vs.85).aspx
 type Win32_Service struct {
 	Name      string
 	State     string

collector/system.go

@@ -1,6 +1,3 @@
-// returns data points from Win32_PerfRawData_PerfOS_System class
-// https://web.archive.org/web/20050830140516/http://msdn.microsoft.com/library/en-us/wmisdk/wmi/win32_perfrawdata_perfos_system.asp
-
 // +build windows
 
 package collector
@@ -80,6 +77,8 @@ func (c *SystemCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_PerfRawData_PerfOS_System docs:
+// - https://web.archive.org/web/20050830140516/http://msdn.microsoft.com/library/en-us/wmisdk/wmi/win32_perfrawdata_perfos_system.asp
 type Win32_PerfRawData_PerfOS_System struct {
 	ContextSwitchesPersec     uint32
 	ExceptionDispatchesPersec uint32

collector/tcp.go

@@ -1,7 +1,3 @@
-// returns data points from Win32_PerfRawData_Tcpip_TCPv4
-
-// https://msdn.microsoft.com/en-us/library/aa394341(v=vs.85).aspx (Win32_PerfRawData_Tcpip_TCPv4 class)
-
 // +build windows
 
 package collector
@@ -102,6 +98,8 @@ func (c *TCPCollector) Collect(ch chan<- prometheus.Metric) error {
 	return nil
 }
 
+// Win32_PerfRawData_Tcpip_TCPv4 docs
+// - https://msdn.microsoft.com/en-us/library/aa394341(v=vs.85).aspx
 type Win32_PerfRawData_Tcpip_TCPv4 struct {
 	ConnectionFailures          uint64
 	ConnectionsActive           uint64

collector/textfile.go

@@ -238,13 +238,16 @@ fileLoop:
 		}
 		var parser expfmt.TextParser
 		r, encoding := utfbom.Skip(carriageReturnFilteringReader{r: file})
-		if err := checkBOM(encoding); err != nil {
+		if err = checkBOM(encoding); err != nil {
 			log.Errorf("Invalid file encoding detected in %s: %s - file must be UTF8", path, err.Error())
 			error = 1.0
 			continue
 		}
 		parsedFamilies, err := parser.TextToMetricFamilies(r)
-		file.Close()
+		closeErr := file.Close()
+		if closeErr != nil {
+			log.Warnf("Error closing file: %v", err)
+		}
 		if err != nil {
 			log.Errorf("Error parsing %q: %v", path, err)
 			error = 1.0

collector/vmware.go

@@ -1,5 +1,3 @@
-// returns data points from Win32_PerfRawData_vmGuestLib_VMem and Win32_PerfRawData_vmGuestLib_VCPU
-
 // +build windows
 
 package collector
@@ -40,6 +38,7 @@ type VmwareCollector struct {
 	HostProcessorSpeedMHz *prometheus.Desc
 }
 
+// NewVmwareCollector constructs a new VmwareCollector
 func NewVmwareCollector() (Collector, error) {
 	const subsystem = "vmware"
 	return &VmwareCollector{

exporter.go

@@ -4,7 +4,6 @@ package main
 
 import (
 	"fmt"
-	"io"
 	"net/http"
 	"sort"
 	"strings"
@@ -222,7 +221,12 @@ func main() {
 
 	stopCh := make(chan bool)
 	if !isInteractive {
-		go svc.Run(serviceName, &wmiExporterService{stopCh: stopCh})
+		go func() {
+			err = svc.Run(serviceName, &wmiExporterService{stopCh: stopCh})
+			if err != nil {
+				log.Errorf("Failed to start service: %v", err)
+			}
+		}()
 	}
 
 	collectors, err := loadCollectors(*enabledCollectors)
@@ -259,7 +263,10 @@ func main() {
 
 func healthCheck(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
-	io.WriteString(w, `{"status":"ok"}`)
+	_, err := fmt.Fprintln(w, `{"status":"ok"}`)
+	if err != nil {
+		log.Debugf("Failed to write to stream: %v", err)
+	}
 }
 
 func keys(m map[string]collector.Collector) []string {

gometalinter.config

@@ -0,0 +1,28 @@
+{
+    "Disable": [
+        "goconst",
+        "gocyclo",
+        "gosec",
+        "maligned",
+        "megacheck"
+    ],
+    "Enable": [
+        "deadcode",
+        "errcheck",
+        "golint",
+        "gotype",
+        "gotypex",
+        "ineffassign",
+        "interfacer",
+        "structcheck",
+        "unconvert",
+        "varcheck",
+        "vet",
+        "vetshadow"
+    ],
+    "Exclude": [
+        "don't use underscores in Go names",
+        "exported type .+ should have comment or be unexported",
+        "should be"
+    ]
+}

tools/collector-generator/collector.template

@@ -1,5 +1,3 @@
-// returns data points from {{ .Class }}
-// <add link to documentation here> - {{ .Class }} class
 package collector
 import (
     "github.com/StackExchange/wmi"
@@ -38,6 +36,8 @@ func (c *{{ .CollectorName }}Collector) Collect(ch chan<- prometheus.Metric) err
     }
     return nil
 }
+// {{ .Class }} docs:
+// - <add link to documentation here>
 type {{ .Class }} struct {
     Name string
 {{ range $m := .Members }}

tools/collector-generator/generate-collector.go

@@ -25,7 +25,7 @@ func main() {
 		panic(err)
 	}
 	var data TemplateData
-	if err := json.Unmarshal(bytes, &data); err != nil {
+	if err = json.Unmarshal(bytes, &data); err != nil {
 		panic(err)
 	}
 
@@ -33,11 +33,11 @@ func main() {
 		"toLower":     strings.ToLower,
 		"toSnakeCase": toSnakeCase,
 	}
-	template, err := template.New("template").Funcs(funcs).ParseFiles("collector.template")
+	tmpl, err := template.New("template").Funcs(funcs).ParseFiles("collector.template")
 	if err != nil {
 		panic(err)
 	}
-	err = template.ExecuteTemplate(os.Stdout, "collector.template", data)
+	err = tmpl.ExecuteTemplate(os.Stdout, "collector.template", data)
 	if err != nil {
 		panic(err)
 	}