chore!: adopt log/slog, drop go-kit/log (#378)

* build(deps): bump prometheus/{client_golang,common,exporter-toolkit}

Also bumps the minimum go version in go.mod to 1.22 to support log/slog,
for exporter-toolkit support.

Signed-off-by: TJ Hoplock <[email protected]>

* chore!: adopt log/slog, drop go-kit/log

The bulk of this PR was automated by the following script which is being
used to aid in converting the various exporters/projects to use slog:

https://gist.github.com/tjhop/49f96fb7ebbe55b12deee0b0312d8434

Other changes include:
- removing unneeded linter settings for go-kit/log
- enabling sloglint linter

Signed-off-by: TJ Hoplock <[email protected]>

---------

Signed-off-by: TJ Hoplock <[email protected]>

Author: tjhop

.golangci.yml

@@ -1,4 +1,8 @@
 ---
+linters:
+  enable:
+  - sloglint
+
 run:
   deadline: 5m
   skip-files:
@@ -16,5 +20,3 @@ linters-settings:
     exclude-functions:
       # Used in HTTP handlers, any error is handled by the server itself.
       - (net/http.ResponseWriter).Write
-      # Never check for logger errors.
-      - (github.com/go-kit/log.Logger).Log

collectors/monitoring_collector.go

@@ -16,13 +16,12 @@ package collectors
 import (
 	"errors"
 	"fmt"
+	"log/slog"
 	"math"
 	"strings"
 	"sync"
 	"time"
 
-	"github.com/go-kit/log"
-	"github.com/go-kit/log/level"
 	"github.com/prometheus/client_golang/prometheus"
 	"golang.org/x/net/context"
 	"google.golang.org/api/monitoring/v3"
@@ -53,7 +52,7 @@ type MonitoringCollector struct {
 	lastScrapeDurationSecondsMetric prometheus.Gauge
 	collectorFillMissingLabels      bool
 	monitoringDropDelegatedProjects bool
-	logger                          log.Logger
+	logger                          *slog.Logger
 	counterStore                    DeltaCounterStore
 	histogramStore                  DeltaHistogramStore
 	aggregateDeltas                 bool
@@ -120,10 +119,10 @@ type DeltaHistogramStore interface {
 	ListMetrics(metricDescriptorName string) []*HistogramMetric
 }
 
-func NewMonitoringCollector(projectID string, monitoringService *monitoring.Service, opts MonitoringCollectorOptions, logger log.Logger, counterStore DeltaCounterStore, histogramStore DeltaHistogramStore) (*MonitoringCollector, error) {
+func NewMonitoringCollector(projectID string, monitoringService *monitoring.Service, opts MonitoringCollectorOptions, logger *slog.Logger, counterStore DeltaCounterStore, histogramStore DeltaHistogramStore) (*MonitoringCollector, error) {
 	const subsystem = "monitoring"
 
-	logger = log.With(logger, "project_id", projectID)
+	logger = logger.With("project_id", projectID)
 
 	apiCallsTotalMetric := prometheus.NewCounter(
 		prometheus.CounterOpts{
@@ -237,7 +236,7 @@ func (c *MonitoringCollector) Collect(ch chan<- prometheus.Metric) {
 	if err := c.reportMonitoringMetrics(ch, begun); err != nil {
 		errorMetric = float64(1)
 		c.scrapeErrorsTotalMetric.Inc()
-		level.Error(c.logger).Log("msg", "Error while getting Google Stackdriver Monitoring metrics", "err", err)
+		c.logger.Error("Error while getting Google Stackdriver Monitoring metrics", "err", err)
 	}
 	c.scrapeErrorsTotalMetric.Collect(ch)
 
@@ -283,7 +282,7 @@ func (c *MonitoringCollector) reportMonitoringMetrics(ch chan<- prometheus.Metri
 			wg.Add(1)
 			go func(metricDescriptor *monitoring.MetricDescriptor, ch chan<- prometheus.Metric, startTime, endTime time.Time) {
 				defer wg.Done()
-				level.Debug(c.logger).Log("msg", "retrieving Google Stackdriver Monitoring metrics for descriptor", "descriptor", metricDescriptor.Type)
+				c.logger.Debug("retrieving Google Stackdriver Monitoring metrics for descriptor", "descriptor", metricDescriptor.Type)
 				filter := fmt.Sprintf("metric.type=\"%s\"", metricDescriptor.Type)
 				if c.monitoringDropDelegatedProjects {
 					filter = fmt.Sprintf(
@@ -298,11 +297,11 @@ func (c *MonitoringCollector) reportMonitoringMetrics(ch chan<- prometheus.Metri
 					ingestDelay := metricDescriptor.Metadata.IngestDelay
 					ingestDelayDuration, err := time.ParseDuration(ingestDelay)
 					if err != nil {
-						level.Error(c.logger).Log("msg", "error parsing ingest delay from metric metadata", "descriptor", metricDescriptor.Type, "err", err, "delay", ingestDelay)
+						c.logger.Error("error parsing ingest delay from metric metadata", "descriptor", metricDescriptor.Type, "err", err, "delay", ingestDelay)
 						errChannel <- err
 						return
 					}
-					level.Debug(c.logger).Log("msg", "adding ingest delay", "descriptor", metricDescriptor.Type, "delay", ingestDelay)
+					c.logger.Debug("adding ingest delay", "descriptor", metricDescriptor.Type, "delay", ingestDelay)
 					endTime = endTime.Add(ingestDelayDuration * -1)
 					startTime = startTime.Add(ingestDelayDuration * -1)
 				}
@@ -313,7 +312,7 @@ func (c *MonitoringCollector) reportMonitoringMetrics(ch chan<- prometheus.Metri
 					}
 				}
 
-				level.Debug(c.logger).Log("msg", "retrieving Google Stackdriver Monitoring metrics with filter", "filter", filter)
+				c.logger.Debug("retrieving Google Stackdriver Monitoring metrics with filter", "filter", filter)
 
 				timeSeriesListCall := c.monitoringService.Projects.TimeSeries.List(utils.ProjectResource(c.projectID)).
 					Filter(filter).
@@ -324,15 +323,15 @@ func (c *MonitoringCollector) reportMonitoringMetrics(ch chan<- prometheus.Metri
 					c.apiCallsTotalMetric.Inc()
 					page, err := timeSeriesListCall.Do()
 					if err != nil {
-						level.Error(c.logger).Log("msg", "error retrieving Time Series metrics for descriptor", "descriptor", metricDescriptor.Type, "err", err)
+						c.logger.Error("error retrieving Time Series metrics for descriptor", "descriptor", metricDescriptor.Type, "err", err)
 						errChannel <- err
 						break
 					}
 					if page == nil {
 						break
 					}
 					if err := c.reportTimeSeriesMetrics(page, metricDescriptor, ch, begun); err != nil {
-						level.Error(c.logger).Log("msg", "error reporting Time Series metrics for descriptor", "descriptor", metricDescriptor.Type, "err", err)
+						c.logger.Error("error reporting Time Series metrics for descriptor", "descriptor", metricDescriptor.Type, "err", err)
 						errChannel <- err
 						break
 					}
@@ -368,7 +367,7 @@ func (c *MonitoringCollector) reportMonitoringMetrics(ch chan<- prometheus.Metri
 			}
 
 			if cached := c.descriptorCache.Lookup(metricsTypePrefix); cached != nil {
-				level.Debug(c.logger).Log("msg", "using cached Google Stackdriver Monitoring metric descriptors starting with", "prefix", metricsTypePrefix)
+				c.logger.Debug("using cached Google Stackdriver Monitoring metric descriptors starting with", "prefix", metricsTypePrefix)
 				if err := metricDescriptorsFunction(cached); err != nil {
 					errChannel <- err
 				}
@@ -381,7 +380,7 @@ func (c *MonitoringCollector) reportMonitoringMetrics(ch chan<- prometheus.Metri
 					return metricDescriptorsFunction(r.MetricDescriptors)
 				}
 
-				level.Debug(c.logger).Log("msg", "listing Google Stackdriver Monitoring metric descriptors starting with", "prefix", metricsTypePrefix)
+				c.logger.Debug("listing Google Stackdriver Monitoring metric descriptors starting with", "prefix", metricsTypePrefix)
 				if err := c.monitoringService.Projects.MetricDescriptors.List(utils.ProjectResource(c.projectID)).
 					Filter(filter).
 					Pages(ctx, callback); err != nil {
@@ -396,7 +395,7 @@ func (c *MonitoringCollector) reportMonitoringMetrics(ch chan<- prometheus.Metri
 	wg.Wait()
 	close(errChannel)
 
-	level.Debug(c.logger).Log("msg", "Done reporting monitoring metrics")
+	c.logger.Debug("Done reporting monitoring metrics")
 	return <-errChannel
 }
 
@@ -500,12 +499,12 @@ func (c *MonitoringCollector) reportTimeSeriesMetrics(
 			if err == nil {
 				timeSeriesMetrics.CollectNewConstHistogram(timeSeries, newestEndTime, labelKeys, dist, buckets, labelValues, timeSeries.MetricKind)
 			} else {
-				level.Debug(c.logger).Log("msg", "discarding", "resource", timeSeries.Resource.Type, "metric",
+				c.logger.Debug("discarding", "resource", timeSeries.Resource.Type, "metric",
 					timeSeries.Metric.Type, "err", err)
 			}
 			continue
 		default:
-			level.Debug(c.logger).Log("msg", "discarding", "value_type", timeSeries.ValueType, "metric", timeSeries)
+			c.logger.Debug("discarding", "value_type", timeSeries.ValueType, "metric", timeSeries)
 			continue
 		}
 
@@ -569,7 +568,7 @@ func (c *MonitoringCollector) generateHistogramBuckets(
 func (c *MonitoringCollector) keyExists(labelKeys []string, key string) bool {
 	for _, item := range labelKeys {
 		if item == key {
-			level.Debug(c.logger).Log("msg", "Found duplicate label key", "key", key)
+			c.logger.Debug("Found duplicate label key", "key", key)
 			return true
 		}
 	}

delta/counter.go

@@ -15,13 +15,12 @@ package delta
 
 import (
 	"fmt"
+	"log/slog"
 	"sort"
 	"strings"
 	"sync"
 	"time"
 
-	"github.com/go-kit/log"
-	"github.com/go-kit/log/level"
 	"google.golang.org/api/monitoring/v3"
 
 	"github.com/prometheus-community/stackdriver_exporter/collectors"
@@ -36,11 +35,11 @@ type MetricEntry struct {
 type InMemoryCounterStore struct {
 	store  *sync.Map
 	ttl    time.Duration
-	logger log.Logger
+	logger *slog.Logger
 }
 
 // NewInMemoryCounterStore returns an implementation of CounterStore which is persisted in-memory
-func NewInMemoryCounterStore(logger log.Logger, ttl time.Duration) *InMemoryCounterStore {
+func NewInMemoryCounterStore(logger *slog.Logger, ttl time.Duration) *InMemoryCounterStore {
 	store := &InMemoryCounterStore{
 		store:  &sync.Map{},
 		logger: logger,
@@ -68,19 +67,19 @@ func (s *InMemoryCounterStore) Increment(metricDescriptor *monitoring.MetricDesc
 	existing := entry.Collected[key]
 
 	if existing == nil {
-		level.Debug(s.logger).Log("msg", "Tracking new counter", "fqName", currentValue.FqName, "key", key, "current_value", currentValue.Value, "incoming_time", currentValue.ReportTime)
+		s.logger.Debug("Tracking new counter", "fqName", currentValue.FqName, "key", key, "current_value", currentValue.Value, "incoming_time", currentValue.ReportTime)
 		entry.Collected[key] = currentValue
 		return
 	}
 
 	if existing.ReportTime.Before(currentValue.ReportTime) {
-		level.Debug(s.logger).Log("msg", "Incrementing existing counter", "fqName", currentValue.FqName, "key", key, "current_value", existing.Value, "adding", currentValue.Value, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
+		s.logger.Debug("Incrementing existing counter", "fqName", currentValue.FqName, "key", key, "current_value", existing.Value, "adding", currentValue.Value, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
 		currentValue.Value = currentValue.Value + existing.Value
 		entry.Collected[key] = currentValue
 		return
 	}
 
-	level.Debug(s.logger).Log("msg", "Ignoring old sample for counter", "fqName", currentValue.FqName, "key", key, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
+	s.logger.Debug("Ignoring old sample for counter", "fqName", currentValue.FqName, "key", key, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
 }
 
 func toCounterKey(c *collectors.ConstMetric) uint64 {
@@ -118,7 +117,7 @@ func (s *InMemoryCounterStore) ListMetrics(metricDescriptorName string) []*colle
 	for key, collected := range entry.Collected {
 		//Scan and remove metrics which are outside the TTL
 		if ttlWindowStart.After(collected.CollectionTime) {
-			level.Debug(s.logger).Log("msg", "Deleting counter entry outside of TTL", "key", key, "fqName", collected.FqName)
+			s.logger.Debug("Deleting counter entry outside of TTL", "key", key, "fqName", collected.FqName)
 			delete(entry.Collected, key)
 			continue
 		}

delta/counter_test.go

@@ -18,7 +18,7 @@ import (
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
-	"github.com/prometheus/common/promlog"
+	"github.com/prometheus/common/promslog"
 	"google.golang.org/api/monitoring/v3"
 
 	"github.com/prometheus-community/stackdriver_exporter/collectors"
@@ -31,7 +31,7 @@ var _ = Describe("Counter", func() {
 	descriptor := &monitoring.MetricDescriptor{Name: "This is a metric"}
 
 	BeforeEach(func() {
-		store = delta.NewInMemoryCounterStore(promlog.New(&promlog.Config{}), time.Minute)
+		store = delta.NewInMemoryCounterStore(promslog.New(&promslog.Config{}), time.Minute)
 		metric = &collectors.ConstMetric{
 			FqName:         "counter_name",
 			LabelKeys:      []string{"labelKey"},

delta/histogram.go

@@ -15,13 +15,12 @@ package delta
 
 import (
 	"fmt"
+	"log/slog"
 	"sort"
 	"strings"
 	"sync"
 	"time"
 
-	"github.com/go-kit/log"
-	"github.com/go-kit/log/level"
 	"google.golang.org/api/monitoring/v3"
 
 	"github.com/prometheus-community/stackdriver_exporter/collectors"
@@ -36,11 +35,11 @@ type HistogramEntry struct {
 type InMemoryHistogramStore struct {
 	store  *sync.Map
 	ttl    time.Duration
-	logger log.Logger
+	logger *slog.Logger
 }
 
 // NewInMemoryHistogramStore returns an implementation of HistogramStore which is persisted in-memory
-func NewInMemoryHistogramStore(logger log.Logger, ttl time.Duration) *InMemoryHistogramStore {
+func NewInMemoryHistogramStore(logger *slog.Logger, ttl time.Duration) *InMemoryHistogramStore {
 	store := &InMemoryHistogramStore{
 		store:  &sync.Map{},
 		logger: logger,
@@ -68,20 +67,20 @@ func (s *InMemoryHistogramStore) Increment(metricDescriptor *monitoring.MetricDe
 	existing := entry.Collected[key]
 
 	if existing == nil {
-		level.Debug(s.logger).Log("msg", "Tracking new histogram", "fqName", currentValue.FqName, "key", key, "incoming_time", currentValue.ReportTime)
+		s.logger.Debug("Tracking new histogram", "fqName", currentValue.FqName, "key", key, "incoming_time", currentValue.ReportTime)
 		entry.Collected[key] = currentValue
 		return
 	}
 
 	if existing.ReportTime.Before(currentValue.ReportTime) {
-		level.Debug(s.logger).Log("msg", "Incrementing existing histogram", "fqName", currentValue.FqName, "key", key, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
+		s.logger.Debug("Incrementing existing histogram", "fqName", currentValue.FqName, "key", key, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
 		currentValue.MergeHistogram(existing)
 		// Replace the existing histogram by the new one after merging it.
 		entry.Collected[key] = currentValue
 		return
 	}
 
-	level.Debug(s.logger).Log("msg", "Ignoring old sample for histogram", "fqName", currentValue.FqName, "key", key, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
+	s.logger.Debug("Ignoring old sample for histogram", "fqName", currentValue.FqName, "key", key, "last_reported_time", existing.ReportTime, "incoming_time", currentValue.ReportTime)
 }
 
 func toHistogramKey(hist *collectors.HistogramMetric) uint64 {
@@ -119,7 +118,7 @@ func (s *InMemoryHistogramStore) ListMetrics(metricDescriptorName string) []*col
 	for key, collected := range entry.Collected {
 		// Scan and remove metrics which are outside the TTL
 		if ttlWindowStart.After(collected.CollectionTime) {
-			level.Debug(s.logger).Log("msg", "Deleting histogram entry outside of TTL", "key", key, "fqName", collected.FqName)
+			s.logger.Debug("Deleting histogram entry outside of TTL", "key", key, "fqName", collected.FqName)
 			delete(entry.Collected, key)
 			continue
 		}

delta/histogram_test.go

@@ -18,7 +18,7 @@ import (
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
-	"github.com/prometheus/common/promlog"
+	"github.com/prometheus/common/promslog"
 	"google.golang.org/api/monitoring/v3"
 
 	"github.com/prometheus-community/stackdriver_exporter/collectors"
@@ -33,7 +33,7 @@ var _ = Describe("HistogramStore", func() {
 	bucketValue := uint64(1000)
 
 	BeforeEach(func() {
-		store = delta.NewInMemoryHistogramStore(promlog.New(&promlog.Config{}), time.Minute)
+		store = delta.NewInMemoryHistogramStore(promslog.New(&promslog.Config{}), time.Minute)
 		histogram = &collectors.HistogramMetric{
 			FqName:         "histogram_name",
 			LabelKeys:      []string{"labelKey"},

go.mod

@@ -1,17 +1,16 @@
 module github.com/prometheus-community/stackdriver_exporter
 
-go 1.21
+go 1.22
 
 require (
 	github.com/PuerkitoBio/rehttp v1.4.0
 	github.com/alecthomas/kingpin/v2 v2.4.0
 	github.com/fatih/camelcase v1.0.0
-	github.com/go-kit/log v0.2.1
 	github.com/onsi/ginkgo v1.16.5
 	github.com/onsi/gomega v1.34.1
-	github.com/prometheus/client_golang v1.20.2
-	github.com/prometheus/common v0.59.1
-	github.com/prometheus/exporter-toolkit v0.11.0
+	github.com/prometheus/client_golang v1.20.5
+	github.com/prometheus/common v0.60.0
+	github.com/prometheus/exporter-toolkit v0.13.0
 	golang.org/x/net v0.29.0
 	golang.org/x/oauth2 v0.23.0
 	google.golang.org/api v0.199.0
@@ -27,7 +26,6 @@ require (
 	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/fsnotify/fsnotify v1.4.9 // indirect
-	github.com/go-logfmt/logfmt v0.5.1 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
@@ -38,6 +36,8 @@ require (
 	github.com/googleapis/gax-go/v2 v2.13.0 // indirect
 	github.com/jpillora/backoff v1.0.0 // indirect
 	github.com/klauspost/compress v1.17.9 // indirect
+	github.com/mdlayher/socket v0.4.1 // indirect
+	github.com/mdlayher/vsock v1.2.1 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/mwitkow/go-conntrack v0.0.0-20190716064945-2f068394615f // indirect
 	github.com/nxadm/tail v1.4.8 // indirect