metrics.go

//
// Copyright (c) 2021 Red Hat, Inc.
// 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 oauth

import (
	"net/http"

	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promhttp"
	"github.com/redhat-appstudio/service-provider-integration-operator/pkg/spi-shared/config"
)

var (
	// HttpServiceRequestCountMetric is the metric that collects the request counts for OAuth Service.
	HttpServiceRequestCountMetric = prometheus.NewCounterVec(
		prometheus.CounterOpts{
			Namespace: config.MetricsNamespace,
			Subsystem: config.MetricsSubsystem,
			Name:      "oauth_service_requests_total",
			Help:      "The request counts to OAuth service categorized by HTTP method status code.",
		},
		[]string{"code", "method"},
	)

	FlowCompleteTimeMetric = prometheus.NewHistogramVec(prometheus.HistogramOpts{
		Namespace: config.MetricsNamespace,
		Subsystem: config.MetricsSubsystem,
		Name:      "oauth_flow_complete_time_seconds",
		Help:      "The time needed to complete OAuth flow",
		Buckets:   []float64{1.0, 1.25, 1.5, 1.75, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, 60, 300},
	}, []string{"type", "url"})
)

// HttpServiceInstrumentMetricHandler is a http.Handler that collects statistical information about
// incoming HTTP request and store it in prometheus.Registerer.
func HttpServiceInstrumentMetricHandler(reg prometheus.Registerer, handler http.Handler) http.Handler {
	reg.MustRegister(HttpServiceRequestCountMetric)
	return promhttp.InstrumentHandlerCounter(HttpServiceRequestCountMetric, handler)
}