Merge pull request #44 from ondat/ctrl-216

Ctrl-216 - Allow to disable metrics collectors

.dockerignore

@@ -6,3 +6,5 @@
 !go.mod
 !go.sum
 !index.html
+# ignore local GOPATH=$(pwd)/.go/
+.go/

Dockerfile

@@ -2,11 +2,12 @@
 FROM golang:1.17.3 as builder
 
 WORKDIR /workspace
-COPY . .
+COPY go.mod go.sum ./
 
 # cache deps before building and copying source so that we don't need to re-download as much
 # and so that source changes don't invalidate our downloaded layer
 RUN go mod download
+COPY . .
 
 # Build
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -a -o metrics-exporter .

api/config.storageos.com/v1/constants.go

@@ -0,0 +1,23 @@
+/*
+Copyright 2022 Ondat.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package v1
+
+const (
+	// MetricsExporterConfigFileName is a mandatory key in the data field of the
+	// ConfigMap/storage-metrics-exporter. The associated value must be a valid MetricsExporterConfig
+	// serialized as YAML.
+	MetricsExporterConfigFileName = "config.yaml"
+)

api/config.storageos.com/v1/default.go

@@ -0,0 +1,26 @@
+/*
+Copyright 2022 Ondat.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package v1
+
+func (c *MetricsExporterConfig) Default() *MetricsExporterConfig {
+	if c.LogLevel == "" {
+		c.LogLevel = "info"
+	}
+	if c.Timeout == 0 {
+		c.Timeout = 10
+	}
+	return c
+}

api/config.storageos.com/v1/metricsexporterconfig_types.go

@@ -28,6 +28,12 @@ type MetricsExporterConfig struct {
 	metav1.TypeMeta   `json:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty"`
 
+	MetricsExporterConfigSpec `json:",inline"`
+}
+
+// MetricsExporterConfigSpec represents the configuration options for the metrics-exporter. These fields shall
+// be inlined in the StorageOSCluster.Spec.Metrics.
+type MetricsExporterConfigSpec struct {
 	// Verbosity of log messages. Accepts go.uber.org/zap log levels.
 	// +kubebuilder:default:info
 	// +kubebuilder:validation:Enum=debug;info;warn;error;dpanic;panic;fatal
@@ -36,9 +42,22 @@ type MetricsExporterConfig struct {
 	// Timeout in seconds to serve metrics.
 	// +kubebuilder:default:10
 	// +kubebuilder:validation:Minimum=1
-	Timeout int `json:"timeout"`
+	Timeout int `json:"timeout,omitempty"`
+
+	// DisabledCollectors is a list of collectors that shall be disabled. By default, all are enabled.
+	DisabledCollectors []MetricsExporterCollector `json:"disabledCollectors,omitempty"`
 }
 
+// MetricsExporterCollector is the name of a metrics collector in the metrics-exporter.
+// +kubebuilder:validation:Enum=diskstats;filesystem
+type MetricsExporterCollector string
+
+// All known metrics-exporter collectors are listed here.
+const (
+	MetricsExporterCollectorDiskStats  MetricsExporterCollector = "diskstats"
+	MetricsExporterCollectorFileSystem MetricsExporterCollector = "filesystem"
+)
+
 func init() {
 	SchemeBuilder.Register(&MetricsExporterConfig{})
 }

collector.go

@@ -7,6 +7,8 @@ import (
 	"github.com/google/uuid"
 	"github.com/prometheus/client_golang/prometheus"
 	"go.uber.org/zap"
+
+	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
 )
 
 type Collector interface {
@@ -77,3 +79,33 @@ func execute(log *zap.SugaredLogger, c Collector, ch chan<- prometheus.Metric, o
 	}
 	ch <- prometheus.MustNewConstMetric(scrapeSuccessMetric.desc, scrapeSuccessMetric.valueType, success, c.Name())
 }
+
+func GetEnabledMetricsCollectors(
+	log *zap.SugaredLogger,
+	disabled []configondatv1.MetricsExporterCollector,
+) []Collector {
+	var metricsCollectors []Collector
+	for name, collectorFactory := range map[configondatv1.MetricsExporterCollector](func() Collector){
+		configondatv1.MetricsExporterCollectorDiskStats:  func() Collector { return NewDiskStatsCollector() },
+		configondatv1.MetricsExporterCollectorFileSystem: func() Collector { return NewFileSystemCollector() },
+	} {
+		if IsCollectorDisabled(disabled, name) {
+			log.Infof("disabling %s collector", name)
+			continue
+		}
+		metricsCollectors = append(metricsCollectors, collectorFactory())
+	}
+	return metricsCollectors
+}
+
+func IsCollectorDisabled(
+	disabled []configondatv1.MetricsExporterCollector,
+	collector configondatv1.MetricsExporterCollector,
+) bool {
+	for _, c := range disabled {
+		if c == collector {
+			return true
+		}
+	}
+	return false
+}

collector_test.go

@@ -0,0 +1,90 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap"
+
+	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
+)
+
+func TestGetEnabledMetricsCollectors(t *testing.T) {
+	tests := []struct {
+		name            string
+		disable         []configondatv1.MetricsExporterCollector
+		expectedEnabled []string
+	}{
+		{
+			name:    "all enabled",
+			disable: nil,
+			expectedEnabled: []string{
+				"diskstats",
+				"filesystem",
+			},
+		},
+
+		{
+			name:    "disable filesystem",
+			disable: []configondatv1.MetricsExporterCollector{configondatv1.MetricsExporterCollectorFileSystem},
+			expectedEnabled: []string{
+				"diskstats",
+			},
+		},
+
+		{
+			name:    "disable diskstats",
+			disable: []configondatv1.MetricsExporterCollector{configondatv1.MetricsExporterCollectorDiskStats},
+			expectedEnabled: []string{
+				"filesystem",
+			},
+		},
+
+		{
+			name: "disable both",
+			disable: []configondatv1.MetricsExporterCollector{
+				configondatv1.MetricsExporterCollectorFileSystem,
+				configondatv1.MetricsExporterCollectorDiskStats,
+			},
+			expectedEnabled: []string{},
+		},
+
+		{
+			name: "disable both - reversed",
+			disable: []configondatv1.MetricsExporterCollector{
+				configondatv1.MetricsExporterCollectorDiskStats,
+				configondatv1.MetricsExporterCollectorFileSystem,
+			},
+			expectedEnabled: []string{},
+		},
+
+		{
+			name: "ignore bad value",
+			disable: []configondatv1.MetricsExporterCollector{
+				configondatv1.MetricsExporterCollector("bad"),
+				configondatv1.MetricsExporterCollectorFileSystem,
+			},
+			expectedEnabled: []string{
+				"diskstats",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		var tt = tt
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			loggerConfig := zap.NewProductionConfig()
+			logger, _ := loggerConfig.Build()
+			log := logger.Sugar()
+
+			collectors := GetEnabledMetricsCollectors(log, tt.disable)
+			names := make([]string, 0, len(collectors))
+			for _, c := range collectors {
+				names = append(names, c.Name())
+			}
+			require.ElementsMatch(t, tt.expectedEnabled, names)
+		})
+	}
+}

config.go

@@ -22,16 +22,10 @@ import (
 	"log"
 	"os"
 
-	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/serializer"
-)
 
-var (
-	configDefaults = configondatv1.MetricsExporterConfig{
-		LogLevel: "info",
-		Timeout:  10,
-	}
+	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
 )
 
 func readConfigFile(path string) (*configondatv1.MetricsExporterConfig, error) {
@@ -42,25 +36,28 @@ func readConfigFile(path string) (*configondatv1.MetricsExporterConfig, error) {
 
 	codecs := serializer.NewCodecFactory(scheme)
 
-	cfg := *configDefaults.DeepCopy()
-	if err = runtime.DecodeInto(codecs.UniversalDecoder(), content, &cfg); err != nil {
+	cfg := (&configondatv1.MetricsExporterConfig{}).Default()
+	if err = runtime.DecodeInto(codecs.UniversalDecoder(), content, cfg); err != nil {
 		return nil, fmt.Errorf("could not decode file into runtime.Object: %v", err)
 	}
-	return &cfg, nil
+
+	return cfg, nil
 }
 
 func getConfigOrDie() (path string, cfg configondatv1.MetricsExporterConfig) {
 	var configFile string
 	var logLevelFlag string
 	var timeoutFlag int
 
+	defaults := (&configondatv1.MetricsExporterConfig{}).Default()
+
 	flag.StringVar(&configFile, "config", "",
 		"The exporter will load its initial configuration from this file. "+
 			"Omit this flag to use the default configuration values. "+
 			"Command-line flags override configuration from this file.")
-	flag.StringVar(&logLevelFlag, "log-level", configDefaults.LogLevel,
+	flag.StringVar(&logLevelFlag, "log-level", defaults.LogLevel,
 		"Verbosity of log messages. Accepts go.uber.org/zap log levels.")
-	flag.IntVar(&timeoutFlag, "timeout", configDefaults.Timeout, "Timeout in seconds to serve metrics.")
+	flag.IntVar(&timeoutFlag, "timeout", defaults.Timeout, "Timeout in seconds to serve metrics.")
 	flag.Parse()
 
 	if len(configFile) > 0 {
@@ -71,7 +68,7 @@ func getConfigOrDie() (path string, cfg configondatv1.MetricsExporterConfig) {
 		}
 		cfg = *parsedCfg
 	} else {
-		cfg = *configDefaults.DeepCopy()
+		cfg = *defaults
 	}
 
 	// override defaults/configmap with the supplied flag values

diskstats_collector.go

@@ -5,13 +5,15 @@ import (
 
 	"github.com/prometheus/client_golang/prometheus"
 	"go.uber.org/zap"
+
+	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
 )
 
 const (
 	// SECOND_IN_MILLISECONDS defines the number of seconds on a milliseconds. Used
 	// to transform metrics that express a duration in milliseconds.
 	SECOND_IN_MILLISECONDS   = 1.0 / 1000.0
-	DISKSTATS_COLLECTOR_NAME = "diskstats"
+	DISKSTATS_COLLECTOR_NAME = string(configondatv1.MetricsExporterCollectorDiskStats)
 )
 
 // DiskStatsCollector implements the prometheus Collector interface

filesystem_collector.go

@@ -13,9 +13,11 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 	"go.uber.org/zap"
 	"golang.org/x/sys/unix"
+
+	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
 )
 
-const FILE_SYSTEM_COLLECTOR_NAME = "filesystem"
+const FILE_SYSTEM_COLLECTOR_NAME = string(configondatv1.MetricsExporterCollectorFileSystem)
 
 var stuckMounts = make(map[string]struct{})
 var stuckMountsMtx = &sync.Mutex{}

main.go

@@ -23,13 +23,14 @@ import (
 	"os"
 	"time"
 
-	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 	"k8s.io/apimachinery/pkg/runtime"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+
+	configondatv1 "github.com/ondat/metrics-exporter/api/config.storageos.com/v1"
 )
 
 const (
@@ -72,9 +73,9 @@ func main() {
 	}
 	log.Debugf("Serve metrics timeout set to %d seconds", cfg.Timeout)
 
-	metricsCollectors := []Collector{
-		NewDiskStatsCollector(),
-		NewFileSystemCollector(),
+	metricsCollectors := GetEnabledMetricsCollectors(log, cfg.DisabledCollectors)
+	if len(metricsCollectors) == 0 {
+		log.Fatal("there is nothing to do with all metrics collectors disabled")
 	}
 
 	prometheusRegistry := prometheus.NewRegistry()