Codebase list golang-github-go-kit-kit / bab34e9 examples / shipping / booking / instrumenting.go
bab34e9

Tree @bab34e9 (Download .tar.gz)

instrumenting.go @bab34e9raw · history · blame

package booking

import (
	"time"

	stdprometheus "github.com/prometheus/client_golang/prometheus"

	"github.com/go-kit/kit/metrics"
	kitprometheus "github.com/go-kit/kit/metrics/prometheus"

	"github.com/go-kit/kit/examples/shipping/cargo"
	"github.com/go-kit/kit/examples/shipping/location"
)

type instrumentingService struct {
	requestCount   metrics.Counter
	requestLatency metrics.TimeHistogram
	Service
}

// NewInstrumentingService returns an instance of an instrumenting Service.
func NewInstrumentingService(s Service) Service {
	fieldKeys := []string{"method"}

	requestCount := kitprometheus.NewCounter(stdprometheus.CounterOpts{
		Namespace: "api",
		Subsystem: "booking_service",
		Name:      "request_count",
		Help:      "Number of requests received.",
	}, fieldKeys)

	requestLatency := metrics.NewTimeHistogram(time.Microsecond, kitprometheus.NewSummary(stdprometheus.SummaryOpts{
		Namespace: "api",
		Subsystem: "booking_service",
		Name:      "request_latency_microseconds",
		Help:      "Total duration of requests in microseconds.",
	}, fieldKeys))

	return &instrumentingService{
		requestCount:   requestCount,
		requestLatency: requestLatency,
		Service:        s,
	}
}

func (s *instrumentingService) BookNewCargo(origin, destination location.UNLocode, arrivalDeadline time.Time) (cargo.TrackingID, error) {
	defer func(begin time.Time) {
		methodField := metrics.Field{Key: "method", Value: "book"}
		s.requestCount.With(methodField).Add(1)
		s.requestLatency.With(methodField).Observe(time.Since(begin))
	}(time.Now())

	return s.Service.BookNewCargo(origin, destination, arrivalDeadline)
}

func (s *instrumentingService) LoadCargo(id cargo.TrackingID) (c Cargo, err error) {
	defer func(begin time.Time) {
		methodField := metrics.Field{Key: "method", Value: "load"}
		s.requestCount.With(methodField).Add(1)
		s.requestLatency.With(methodField).Observe(time.Since(begin))
	}(time.Now())

	return s.Service.LoadCargo(id)
}

func (s *instrumentingService) RequestPossibleRoutesForCargo(id cargo.TrackingID) []cargo.Itinerary {
	defer func(begin time.Time) {
		methodField := metrics.Field{Key: "method", Value: "request_routes"}
		s.requestCount.With(methodField).Add(1)
		s.requestLatency.With(methodField).Observe(time.Since(begin))
	}(time.Now())

	return s.Service.RequestPossibleRoutesForCargo(id)
}

func (s *instrumentingService) AssignCargoToRoute(id cargo.TrackingID, itinerary cargo.Itinerary) (err error) {
	defer func(begin time.Time) {
		methodField := metrics.Field{Key: "method", Value: "assign_to_route"}
		s.requestCount.With(methodField).Add(1)
		s.requestLatency.With(methodField).Observe(time.Since(begin))
	}(time.Now())

	return s.Service.AssignCargoToRoute(id, itinerary)
}

func (s *instrumentingService) ChangeDestination(id cargo.TrackingID, l location.UNLocode) (err error) {
	defer func(begin time.Time) {
		methodField := metrics.Field{Key: "method", Value: "change_destination"}
		s.requestCount.With(methodField).Add(1)
		s.requestLatency.With(methodField).Observe(time.Since(begin))
	}(time.Now())

	return s.Service.ChangeDestination(id, l)
}

func (s *instrumentingService) Cargos() []Cargo {
	defer func(begin time.Time) {
		methodField := metrics.Field{Key: "method", Value: "list_cargos"}
		s.requestCount.With(methodField).Add(1)
		s.requestLatency.With(methodField).Observe(time.Since(begin))
	}(time.Now())

	return s.Service.Cargos()
}

func (s *instrumentingService) Locations() []Location {
	defer func(begin time.Time) {
		methodField := metrics.Field{Key: "method", Value: "list_locations"}
		s.requestCount.With(methodField).Add(1)
		s.requestLatency.With(methodField).Observe(time.Since(begin))
	}(time.Now())

	return s.Service.Locations()
}