vendor: revendor

Signed-off-by: Lucas Servén Marín <lserven@gmail.com>

vendor/github.com/metalmatze/signal/healthcheck/metrics_handler.go

@@ -0,0 +1,72 @@
+// Copyright 2020 by the contributors.
+//
+// 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 healthcheck
+
+import (
+	"net/http"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type metricsHandler struct {
+	handler  Handler
+	registry prometheus.Registerer
+}
+
+// NewMetricsHandler returns a healthy Handler that writes the current check status
+// into the provided Prometheus registry.
+func NewMetricsHandler(handler Handler, registry prometheus.Registerer) Handler {
+	return &metricsHandler{
+		handler:  handler,
+		registry: registry,
+	}
+}
+
+func (h *metricsHandler) AddLivenessCheck(name string, check Check) {
+	h.handler.AddLivenessCheck(name, h.wrap(prometheus.Labels{"name": name, "check": "live"}, check))
+}
+
+func (h *metricsHandler) AddReadinessCheck(name string, check Check) {
+	h.handler.AddReadinessCheck(name, h.wrap(prometheus.Labels{"name": name, "check": "ready"}, check))
+}
+
+func (h *metricsHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	h.handler.ServeHTTP(w, r)
+}
+
+func (h *metricsHandler) LiveEndpoint(w http.ResponseWriter, r *http.Request) {
+	h.handler.LiveEndpoint(w, r)
+}
+
+func (h *metricsHandler) ReadyEndpoint(w http.ResponseWriter, r *http.Request) {
+	h.handler.ReadyEndpoint(w, r)
+}
+
+func (h *metricsHandler) wrap(labels prometheus.Labels, check Check) Check {
+	h.registry.MustRegister(prometheus.NewGaugeFunc(
+		prometheus.GaugeOpts{
+			Name:        "healthcheck",
+			Help:        "Indicates if check is healthy (1 is healthy, 0 is unhealthy)",
+			ConstLabels: labels,
+		},
+		func() float64 {
+			if check() != nil {
+				return 0
+			}
+			return 1
+		},
+	))
+	return check
+}