metrics have been added

1 files changed, 254 insertions, 0 deletions

diff --git a/library/go/core/metrics/prometheus/registry.go b/library/go/core/metrics/prometheus/registry.go
new file mode 100644
index 0000000000..bad45fe617
--- /dev/null
+++ b/library/go/core/metrics/prometheus/registry.go
@@ -0,0 +1,254 @@
+package prometheus
+
+import (
+	"sync"
+
+	"github.com/prometheus/client_golang/prometheus"
+	dto "github.com/prometheus/client_model/go"
+	"github.com/ydb-platform/ydb/library/go/core/metrics"
+	"github.com/ydb-platform/ydb/library/go/core/metrics/internal/pkg/metricsutil"
+	"github.com/ydb-platform/ydb/library/go/core/metrics/internal/pkg/registryutil"
+	"github.com/ydb-platform/ydb/library/go/core/xerrors"
+)
+
+var _ metrics.Registry = (*Registry)(nil)
+
+type Registry struct {
+	rg *prometheus.Registry
+
+	m             *sync.Mutex
+	subregistries map[string]*Registry
+
+	tags          map[string]string
+	prefix        string
+	nameSanitizer func(string) string
+}
+
+// NewRegistry creates new Prometheus backed registry.
+func NewRegistry(opts *RegistryOpts) *Registry {
+	r := &Registry{
+		rg:            prometheus.NewRegistry(),
+		m:             new(sync.Mutex),
+		subregistries: make(map[string]*Registry),
+		tags:          make(map[string]string),
+	}
+
+	if opts != nil {
+		r.prefix = opts.Prefix
+		r.tags = opts.Tags
+		if opts.rg != nil {
+			r.rg = opts.rg
+		}
+		for _, collector := range opts.Collectors {
+			collector(r)
+		}
+		if opts.NameSanitizer != nil {
+			r.nameSanitizer = opts.NameSanitizer
+		}
+	}
+
+	return r
+}
+
+// WithTags creates new sub-scope, where each metric has tags attached to it.
+func (r Registry) WithTags(tags map[string]string) metrics.Registry {
+	return r.newSubregistry(r.prefix, registryutil.MergeTags(r.tags, tags))
+}
+
+// WithPrefix creates new sub-scope, where each metric has prefix added to it name.
+func (r Registry) WithPrefix(prefix string) metrics.Registry {
+	return r.newSubregistry(registryutil.BuildFQName("_", r.prefix, prefix), r.tags)
+}
+
+// ComposeName builds FQ name with appropriate separator.
+func (r Registry) ComposeName(parts ...string) string {
+	return registryutil.BuildFQName("_", parts...)
+}
+
+func (r Registry) Counter(name string) metrics.Counter {
+	name = r.sanitizeName(name)
+	cnt := prometheus.NewCounter(prometheus.CounterOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+	})
+
+	if err := r.rg.Register(cnt); err != nil {
+		var existErr prometheus.AlreadyRegisteredError
+		if xerrors.As(err, &existErr) {
+			return &Counter{cnt: existErr.ExistingCollector.(prometheus.Counter)}
+		}
+		panic(err)
+	}
+
+	return &Counter{cnt: cnt}
+}
+
+func (r Registry) FuncCounter(name string, function func() int64) metrics.FuncCounter {
+	name = r.sanitizeName(name)
+	cnt := prometheus.NewCounterFunc(prometheus.CounterOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+	}, func() float64 {
+		return float64(function())
+	})
+
+	if err := r.rg.Register(cnt); err != nil {
+		panic(err)
+	}
+
+	return &FuncCounter{
+		cnt:      cnt,
+		function: function,
+	}
+}
+
+func (r Registry) Gauge(name string) metrics.Gauge {
+	name = r.sanitizeName(name)
+	gg := prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+	})
+
+	if err := r.rg.Register(gg); err != nil {
+		var existErr prometheus.AlreadyRegisteredError
+		if xerrors.As(err, &existErr) {
+			return &Gauge{gg: existErr.ExistingCollector.(prometheus.Gauge)}
+		}
+		panic(err)
+	}
+
+	return &Gauge{gg: gg}
+}
+
+func (r Registry) FuncGauge(name string, function func() float64) metrics.FuncGauge {
+	name = r.sanitizeName(name)
+	ff := prometheus.NewGaugeFunc(prometheus.GaugeOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+	}, function)
+	if err := r.rg.Register(ff); err != nil {
+		panic(err)
+	}
+	return &FuncGauge{
+		ff:       ff,
+		function: function,
+	}
+}
+
+func (r Registry) IntGauge(name string) metrics.IntGauge {
+	return &IntGauge{Gauge: r.Gauge(name)}
+}
+
+func (r Registry) FuncIntGauge(name string, function func() int64) metrics.FuncIntGauge {
+	name = r.sanitizeName(name)
+	ff := prometheus.NewGaugeFunc(prometheus.GaugeOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+	}, func() float64 { return float64(function()) })
+	if err := r.rg.Register(ff); err != nil {
+		panic(err)
+	}
+	return &FuncIntGauge{
+		ff:       ff,
+		function: function,
+	}
+}
+
+func (r Registry) Timer(name string) metrics.Timer {
+	name = r.sanitizeName(name)
+	gg := prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+	})
+
+	if err := r.rg.Register(gg); err != nil {
+		var existErr prometheus.AlreadyRegisteredError
+		if xerrors.As(err, &existErr) {
+			return &Timer{gg: existErr.ExistingCollector.(prometheus.Gauge)}
+		}
+		panic(err)
+	}
+
+	return &Timer{gg: gg}
+}
+
+func (r Registry) Histogram(name string, buckets metrics.Buckets) metrics.Histogram {
+	name = r.sanitizeName(name)
+	hm := prometheus.NewHistogram(prometheus.HistogramOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+		Buckets:     metricsutil.BucketsBounds(buckets),
+	})
+
+	if err := r.rg.Register(hm); err != nil {
+		var existErr prometheus.AlreadyRegisteredError
+		if xerrors.As(err, &existErr) {
+			return &Histogram{hm: existErr.ExistingCollector.(prometheus.Observer)}
+		}
+		panic(err)
+	}
+
+	return &Histogram{hm: hm}
+}
+
+func (r Registry) DurationHistogram(name string, buckets metrics.DurationBuckets) metrics.Timer {
+	name = r.sanitizeName(name)
+	hm := prometheus.NewHistogram(prometheus.HistogramOpts{
+		Namespace:   r.prefix,
+		Name:        name,
+		ConstLabels: r.tags,
+		Buckets:     metricsutil.DurationBucketsBounds(buckets),
+	})
+
+	if err := r.rg.Register(hm); err != nil {
+		var existErr prometheus.AlreadyRegisteredError
+		if xerrors.As(err, &existErr) {
+			return &Histogram{hm: existErr.ExistingCollector.(prometheus.Histogram)}
+		}
+		panic(err)
+	}
+
+	return &Histogram{hm: hm}
+}
+
+// Gather returns raw collected Prometheus metrics.
+func (r Registry) Gather() ([]*dto.MetricFamily, error) {
+	return r.rg.Gather()
+}
+
+func (r *Registry) newSubregistry(prefix string, tags map[string]string) *Registry {
+	registryKey := registryutil.BuildRegistryKey(prefix, tags)
+
+	r.m.Lock()
+	defer r.m.Unlock()
+
+	if old, ok := r.subregistries[registryKey]; ok {
+		return old
+	}
+
+	subregistry := &Registry{
+		rg:            r.rg,
+		m:             r.m,
+		subregistries: r.subregistries,
+		tags:          tags,
+		prefix:        prefix,
+		nameSanitizer: r.nameSanitizer,
+	}
+
+	r.subregistries[registryKey] = subregistry
+	return subregistry
+}
+
+func (r *Registry) sanitizeName(name string) string {
+	if r.nameSanitizer == nil {
+		return name
+	}
+	return r.nameSanitizer(name)
+}