Link collectors to config and logging

cmd/server/main.go

@@ -37,14 +37,21 @@ func main() {
 		os.Exit(1)
 	}
 
-	logger, err := conf.ZapConfig().Build()
+	rawL, err := conf.ZapConfig().Build()
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "Failed to init logger: %s\n", err)
 		os.Exit(1)
 	}
+	logger := rawL.Sugar()
+	logger.Infof("Initialized logger to %v level", logger.Level())
+
+	logger.Infof("Loading %d collectors", len(conf.Collectors))
+	if len(conf.Collectors) == 0 {
+		logger.Warn("No collector present in the config, is this expected?")
+	}
 
 	logger.Info("Starting server")
-	registry.R.Run(context.Background())
+	registry.R.Run(context.Background(), conf, logger)
 
 	http.Handle("/metrics", promhttp.HandlerFor(registry.R.PromRegistry(), promhttp.HandlerOpts{}))
 	http.ListenAndServe(":2112", nil)

collector/collector.go

@@ -4,10 +4,11 @@ import (
 	"context"
 
 	"github.com/prometheus/client_golang/prometheus"
+	"go.uber.org/zap"
 )
 
 type Collector interface {
 	Collect() interface{}
 	PromCollector() prometheus.Collector
-	Run(ctx context.Context)
+	Run(ctx context.Context, l *zap.SugaredLogger)
 }

collector/loadavg/loadavg.go

@@ -10,6 +10,7 @@ import (
 
 	"git.faercol.me/monitoring/sys-exporter/registry"
 	"github.com/prometheus/client_golang/prometheus"
+	"go.uber.org/zap"
 )
 
 const loadAvgFileLocation = "/proc/loadavg"
@@ -18,6 +19,7 @@ type LoadAvgCollector struct {
 	loadAvgFileLocation string
 	promExporter        *prometheus.SummaryVec
 	updateFreq          time.Duration
+	l                   *zap.SugaredLogger
 }
 
 func (c *LoadAvgCollector) Collect() interface{} {
@@ -52,18 +54,23 @@ func (c *LoadAvgCollector) update() error {
 	return nil
 }
 
-func (c *LoadAvgCollector) Run(ctx context.Context) {
+func (c *LoadAvgCollector) Run(ctx context.Context, l *zap.SugaredLogger) {
+	c.l = l
+
+	c.l.Debug("Initializing collector")
 	if err := c.update(); err != nil {
-		fmt.Printf("Failed to init loadavg collector: %s\n", err)
+		c.l.Errorf("Failed to init collector: %s\n", err)
 	}
 
 	for {
 		select {
 		case <-ctx.Done():
+			c.l.Debug("Stopping collector")
 			return
 		case <-time.After(c.updateFreq):
+			c.l.Debug("Updating collector")
 			if err := c.update(); err != nil {
-				fmt.Printf("Failed to update loadavg collector: %s\n", err)
+				c.l.Errorf("Failed to update collector: %s\n", err)
 			}
 		}
 	}

collector/meminfo/meminfo.go

@@ -12,6 +12,7 @@ import (
 	"git.faercol.me/monitoring/sys-exporter/registry"
 	"git.faercol.me/monitoring/sys-exporter/utils"
 	"github.com/prometheus/client_golang/prometheus"
+	"go.uber.org/zap"
 )
 
 const meminfoFileLocation = "/proc/meminfo"
@@ -51,6 +52,8 @@ type MeminfoCollector struct {
 
 	promExporter *prometheus.SummaryVec
 	updateFreq   time.Duration
+
+	l *zap.SugaredLogger
 }
 
 func (c *MeminfoCollector) Collect() interface{} {
@@ -80,18 +83,23 @@ func (c *MeminfoCollector) update() error {
 	return nil
 }
 
-func (c *MeminfoCollector) Run(ctx context.Context) {
+func (c *MeminfoCollector) Run(ctx context.Context, l *zap.SugaredLogger) {
+	c.l = l
+
+	c.l.Debug("Initializing collector")
 	if err := c.update(); err != nil {
-		fmt.Printf("Failed to init meminfo collector: %s\n", err)
+		c.l.Errorf("Failed to init collector: %s\n", err)
 	}
 
 	for {
 		select {
 		case <-ctx.Done():
+			c.l.Debug("Stopping collector")
 			return
 		case <-time.After(c.updateFreq):
+			c.l.Debug("Updating collector")
 			if err := c.update(); err != nil {
-				fmt.Printf("Failed to update meminfo collector: %s\n", err)
+				c.l.Errorf("Failed to update collector: %s\n", err)
 			}
 		}
 	}

collector/pacman/pacman.go

@@ -9,6 +9,7 @@ import (
 
 	"git.faercol.me/monitoring/sys-exporter/registry"
 	"github.com/prometheus/client_golang/prometheus"
+	"go.uber.org/zap"
 )
 
 const (
@@ -34,6 +35,8 @@ type PacmanCollector struct {
 	promPackages      *prometheus.GaugeVec
 	pendingUpdates    int
 	updateFreq        time.Duration
+
+	l *zap.SugaredLogger
 }
 
 func (c *PacmanCollector) Collect() interface{} {
@@ -70,24 +73,29 @@ func (c *PacmanCollector) updatePendingUpdates() error {
 	return nil
 }
 
-func (c *PacmanCollector) Run(ctx context.Context) {
+func (c *PacmanCollector) Run(ctx context.Context, l *zap.SugaredLogger) {
+	c.l = l
+
+	c.l.Debug("Initializing collector")
 	if err := c.updateInstalledPackages(); err != nil {
-		fmt.Printf("Failed to init count of installed packages: %s\n", err)
+		c.l.Errorf("Failed to init count of installed packages: %s\n", err)
 	}
 	if err := c.updatePendingUpdates(); err != nil {
-		fmt.Printf("Failed to init count of updates: %s\n", err)
+		c.l.Errorf("Failed to init count of updates: %s\n", err)
 	}
 
 	for {
 		select {
 		case <-ctx.Done():
+			c.l.Debug("Stopping collector")
 			return
 		case <-time.After(c.updateFreq):
+			c.l.Debug("Updating collector")
 			if err := c.updateInstalledPackages(); err != nil {
-				fmt.Printf("Failed to update count of installed packages: %s\n", err)
+				c.l.Errorf("Failed to update count of installed packages: %s\n", err)
 			}
 			if err := c.updatePendingUpdates(); err != nil {
-				fmt.Printf("Failed to update count of updates: %s\n", err)
+				c.l.Errorf("Failed to update count of updates: %s\n", err)
 			}
 		}
 	}

collector/systemd/systemd.go

@@ -10,6 +10,7 @@ import (
 
 	"git.faercol.me/monitoring/sys-exporter/registry"
 	"github.com/prometheus/client_golang/prometheus"
+	"go.uber.org/zap"
 )
 
 type serviceStatus struct {
@@ -31,6 +32,8 @@ func (s serviceStatus) unitType() string {
 type SystemdCollector struct {
 	promExporter *prometheus.GaugeVec
 	updateFreq   time.Duration
+
+	l *zap.SugaredLogger
 }
 
 func (c *SystemdCollector) Collect() interface{} {
@@ -97,18 +100,23 @@ func (c *SystemdCollector) update() error {
 	return nil
 }
 
-func (c *SystemdCollector) Run(ctx context.Context) {
+func (c *SystemdCollector) Run(ctx context.Context, l *zap.SugaredLogger) {
+	c.l = l
+
+	c.l.Debug("Initializing collector")
 	if err := c.update(); err != nil {
-		fmt.Printf("Failed to init systemd status: %s\n", err)
+		c.l.Errorf("Failed to init collector: %s\n", err)
 	}
 
 	for {
 		select {
 		case <-ctx.Done():
+			c.l.Debug("Stopping collector")
 			return
 		case <-time.After(c.updateFreq):
+			c.l.Debug("Updating collector")
 			if err := c.update(); err != nil {
-				fmt.Printf("Failed to update systemd status: %s\n", err)
+				c.l.Errorf("Failed to update collector: %s\n", err)
 			}
 		}
 	}

collector/uptime/uptime.go

@@ -10,6 +10,7 @@ import (
 
 	"git.faercol.me/monitoring/sys-exporter/registry"
 	"github.com/prometheus/client_golang/prometheus"
+	"go.uber.org/zap"
 )
 
 const procUptimeLocation = "/proc/uptime"
@@ -20,6 +21,8 @@ type UptimeCollector struct {
 	uptimeFreq       time.Duration
 	uptime           time.Duration
 	uptimeProm       prometheus.Gauge
+
+	l *zap.SugaredLogger
 }
 
 func (c *UptimeCollector) Collect() interface{} {
@@ -51,18 +54,23 @@ func (c *UptimeCollector) PromCollector() prometheus.Collector {
 	return c.uptimeProm
 }
 
-func (c *UptimeCollector) Run(ctx context.Context) {
+func (c *UptimeCollector) Run(ctx context.Context, l *zap.SugaredLogger) {
+	c.l = l
+
+	c.l.Debug("Initializing collector")
 	if err := c.update(); err != nil {
-		fmt.Printf("Failed to init collector: %s\n", err)
+		c.l.Errorf("Failed to init collector: %s\n", err)
 	}
 
 	for {
 		select {
 		case <-ctx.Done():
+			c.l.Debug("Stopping collector")
 			return
 		case <-time.After(c.uptimeFreq):
+			c.l.Debug("Updating collector")
 			if err := c.update(); err != nil {
-				fmt.Printf("Failed to update collector: %s\n", err)
+				c.l.Errorf("Failed to update collector: %s\n", err)
 			}
 		}
 	}

config/config.go

@@ -27,6 +27,7 @@ func (c logConfigJson) logConfig() (LogConfig, error) {
 
 type appConfigJson struct {
 	LogConfig  logConfigJson `yaml:"logging"`
+	Collectors []string      `yaml:"collectors"`
 }
 
 func (c appConfigJson) appConfig() (AppConfig, error) {
@@ -37,6 +38,7 @@ func (c appConfigJson) appConfig() (AppConfig, error) {
 
 	return AppConfig{
 		LogConfig:  lc,
+		Collectors: c.Collectors,
 	}, nil
 }
 
@@ -45,7 +47,6 @@ type LogConfig struct {
 }
 
 func (c *LogConfig) ZapConfig() zap.Config {
-	fmt.Println(c.Level)
 	zapC := zap.Config{
 		Level:            c.Level,
 		Development:      true, // TODO: remove later
@@ -61,7 +62,8 @@ func (c *LogConfig) ZapConfig() zap.Config {
 }
 
 type AppConfig struct {
-	LogConfig `yaml:"logging"`
+	LogConfig
+	Collectors []string
 }
 
 func New(filepath string) (*AppConfig, error) {

registry/registry.go

@@ -4,7 +4,9 @@ import (
 	"context"
 
 	"git.faercol.me/monitoring/sys-exporter/collector"
+	"git.faercol.me/monitoring/sys-exporter/config"
 	"github.com/prometheus/client_golang/prometheus"
+	"go.uber.org/zap"
 )
 
 var R CollectorRegistry
@@ -12,6 +14,8 @@ var R CollectorRegistry
 type CollectorRegistry struct {
 	promRegistry *prometheus.Registry
 	collectors   map[string]collector.Collector
+	conf         *config.AppConfig
+	l            *zap.SugaredLogger
 }
 
 func (r *CollectorRegistry) RegisterCollector(name string, c collector.Collector) error {
@@ -28,10 +32,24 @@ func (r *CollectorRegistry) PromRegistry() *prometheus.Registry {
 	return r.promRegistry
 }
 
-func (r *CollectorRegistry) Run(ctx context.Context) {
+func (r *CollectorRegistry) Run(ctx context.Context, conf *config.AppConfig, l *zap.SugaredLogger) {
-	for _, c := range r.collectors {
+	r.l = l
-		go c.Run(ctx)
+	r.conf = conf
+
+	r.l.Info("Starting all collectors")
+	loaded := 0
+	for _, enabledCollector := range r.conf.Collectors {
+		c, ok := r.collectors[enabledCollector]
+		if ok {
+			r.l.Debugf("Starting collector %s", enabledCollector)
+			go c.Run(ctx, r.l.With("collector", enabledCollector))
+			loaded++
+		} else {
+			r.l.Warnf("Collector %s does not exist, ignoring", enabledCollector)
 		}
+	}
+
+	r.l.Infof("Started %d collectors", loaded)
 }
 
 func init() {