Prometheous (#7)

* OData no longer defaulted, using header to cause it

* Simpler value

* Add Prometheus endpoint

Based on ory#827

JIRA: WAP-1891

cmd/server/handler.go

@@ -102,14 +102,16 @@ func RunHost(c *config.Config) func(cmd *cobra.Command, args []string) {
 
 		n := negroni.New()
 
-		metrics := c.GetMetrics()
+		telemetryMetrics := c.GetTelemetryMetrics()
 		if ok, _ := cmd.Flags().GetBool("disable-telemetry"); !ok && os.Getenv("DISABLE_TELEMETRY") != "1" {
-			go metrics.RegisterSegment(c.BuildVersion, c.BuildHash, c.BuildTime)
-			go metrics.CommitTelemetry()
-			go metrics.TickKeepAlive()
-			n.Use(metrics)
+			go telemetryMetrics.RegisterSegment(c.BuildVersion, c.BuildHash, c.BuildTime)
+			go telemetryMetrics.CommitTelemetry()
+			go telemetryMetrics.TickKeepAlive()
+			n.Use(telemetryMetrics)
 		}
 
+		n.Use(c.GetPrometheusMetrics())
+
 		n.Use(negronilogrus.NewMiddlewareFromLogger(logger, c.Issuer))
 		n.UseFunc(serverHandler.rejectInsecureRequests)
 		n.UseHandler(router)

cmd/server/handler_health_factory.go

@@ -23,7 +23,7 @@ import (
 
 func newHealthHandler(c *config.Config, router *httprouter.Router) *health.Handler {
 	h := &health.Handler{
-		Metrics:        c.GetMetrics(),
+		Metrics:        c.GetTelemetryMetrics(),
 		H:              herodot.NewJSONWriter(c.GetLogger()),
 		W:              c.Context().Warden,
 		ResourcePrefix: c.AccessControlResourcePrefix,

config/config.go

@@ -26,7 +26,6 @@ import (
 	"os"
 	"strings"
 	"time"
-
 	"github.com/ory/ladon"
 	lmem "github.com/ory/ladon/manager/memory"
 	lsql "github.com/ory/ladon/manager/sql"
@@ -38,11 +37,12 @@ import (
 	foauth2 "github.com/spotxchange/fosite/handler/oauth2"
 	"github.com/spotxchange/fosite/token/hmac"
 	"github.com/spotxchange/hydra/health"
-	"github.com/spotxchange/hydra/metrics"
-	"github.com/spotxchange/hydra/pkg"
+	"github.com/spotxchange/hydra/metrics/telemetry"
+	"github.com/spotxchange/hydra/metrics/prometheus"
 	"github.com/spotxchange/hydra/warden/group"
-	"golang.org/x/oauth2"
+	"github.com/spotxchange/hydra/pkg"
 	"golang.org/x/oauth2/clientcredentials"
+	"golang.org/x/oauth2"
 	"gopkg.in/yaml.v2"
 )
 
@@ -81,7 +81,8 @@ type Config struct {
 	BuildHash                        string                  `yaml:"-"`
 	BuildTime                        string                  `yaml:"-"`
 	logger                           *logrus.Logger          `yaml:"-"`
-	metrics                          *metrics.MetricsManager `yaml:"-"`
+	telemetry                          *telemetry.MetricsManager `yaml:"-"`
+	prometheus   *prometheus.MetricsManager `yaml:"-"`
 	cluster                          *url.URL                `yaml:"-"`
 	oauth2Client                     *http.Client            `yaml:"-"`
 	context                          *Context                `yaml:"-"`
@@ -143,12 +144,21 @@ func (c *Config) GetLogger() *logrus.Logger {
 	return c.logger
 }
 
-func (c *Config) GetMetrics() *metrics.MetricsManager {
-	if c.metrics == nil {
-		c.metrics = metrics.NewMetricsManager(c.Issuer, c.DatabaseURL, c.GetLogger())
+func (c *Config) GetTelemetryMetrics() *telemetry.MetricsManager {
+	if c.telemetry == nil {
+		c.telemetry = telemetry.NewMetricsManager(c.Issuer, c.DatabaseURL, c.GetLogger())
+	}
+
+	return c.telemetry
+}
+
+func (c *Config) GetPrometheusMetrics() *prometheus.MetricsManager {
+	if c.prometheus == nil {
+		c.GetLogger().Info("Setting up Prometheus metrics")
+		c.prometheus = prometheus.NewMetricsManager(c.BuildVersion, c.BuildHash, c.BuildTime)
 	}
 
-	return c.metrics
+	return c.prometheus
 }
 
 func (c *Config) DoesRequestSatisfyTermination(r *http.Request) error {

health/handler.go

@@ -20,16 +20,18 @@ import (
 	"github.com/julienschmidt/httprouter"
 	"github.com/ory/herodot"
 	"github.com/spotxchange/hydra/firewall"
-	"github.com/spotxchange/hydra/metrics"
+	"github.com/spotxchange/hydra/metrics/telemetry"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 const (
 	HealthStatusPath  = "/health/status"
 	HealthMetricsPath = "/health/metrics"
+	PrometheusStatusPath = "/health/prometheus"
 )
 
 type Handler struct {
-	Metrics        *metrics.MetricsManager
+	Metrics        *telemetry.MetricsManager
 	H              *herodot.JSONWriter
 	W              firewall.Firewall
 	ResourcePrefix string
@@ -50,6 +52,7 @@ func (h *Handler) PrefixResource(resource string) string {
 func (h *Handler) SetRoutes(r *httprouter.Router) {
 	r.GET(HealthStatusPath, h.Health)
 	r.GET(HealthMetricsPath, h.Statistics)
+	r.Handler("GET", PrometheusStatusPath, promhttp.Handler())
 }
 
 // swagger:route GET /health/status health getInstanceStatus

metrics/prometheus/metrics.go

@@ -0,0 +1,42 @@
+package prometheus
+
+// Metrics prototypes
+// Example:
+// 	Counter      *prometheus.CounterVec
+// 	ResponseTime *prometheus.HistogramVec
+type Metrics struct{}
+
+// Method for creation new custom Prometheus  metrics
+// Example:
+// 	pm := &Metrics{
+//		Counter: prometheus.NewCounterVec(
+//			prometheus.CounterOpts{
+//				Name:        "servicename_requests_total",
+//				Help:        "Description",
+//				ConstLabels: map[string]string{
+//					"version":   version,
+//					"hash":      hash,
+//					"buildTime": buildTime,
+//				},
+//			},
+//			[]string{"endpoint"},
+//		),
+//		ResponseTime: prometheus.NewHistogramVec(
+//			prometheus.HistogramOpts{
+//				Name:        "servicename_response_time_seconds",
+//				Help:        "Description",
+//				ConstLabels: map[string]string{
+//					"version":   version,
+//					"hash":      hash,
+//					"buildTime": buildTime,
+//				},
+//			},
+//			[]string{"endpoint"},
+//		),
+//	}
+//	prometheus.Register(pm.Counter)
+//  prometheus.Register(pm.ResponseTime)
+func NewMetrics(version, hash, buildTime string) *Metrics {
+	pm := &Metrics{}
+	return pm
+}

metrics/prometheus/middleware.go

@@ -0,0 +1,27 @@
+package prometheus
+
+import (
+	"net/http"
+)
+
+type MetricsManager struct {
+	prometheusMetrics *Metrics
+}
+
+func NewMetricsManager(version, hash, buildTime string) *MetricsManager {
+	return &MetricsManager{
+		prometheusMetrics: NewMetrics(version, hash, buildTime),
+	}
+}
+
+// Main middleware method to collect metrics for Prometheus.
+// Example:
+//	start := time.Now()
+//	next(rw, r)
+//	Request counter metric
+//	pmm.prometheusMetrics.Counter.WithLabelValues(r.URL.Path).Inc()
+//	Response time metric
+//	pmm.prometheusMetrics.ResponseTime.WithLabelValues(r.URL.Path).Observe(time.Since(start).Seconds())
+func (pmm *MetricsManager) ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
+	next(rw, r)
+}

metrics/metrics.go → metrics/telemetry/metrics.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package metrics
+package telemetry
 
 import (
 	"runtime"

metrics/middleware.go → metrics/telemetry/middleware.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package metrics
+package telemetry
 
 import (
 	"net/http"

metrics/middleware_test.go → metrics/telemetry/middleware_test.go

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package metrics_test
+package telemetry
 
 import (
 	"fmt"