metrics.go

/**
 * Copyright 2020 Comcast Cable Communications Management, LLC
 *
 * 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 main

import (
	"github.com/prometheus/client_golang/prometheus"
	"github.com/xmidt-org/themis/xmetrics"
	"github.com/xmidt-org/themis/xmetrics/xmetricshttp"
	"go.uber.org/fx"
)

const ServerLabel = "server"

// provideMetrics builds the application metrics and makes them available to the container
func provideMetrics() fx.Option {
	return fx.Provide(
		xmetrics.ProvideCounterVec(
			prometheus.CounterOpts{
				Name: "server_request_count",
				Help: "total incoming HTTP requests",
			},
			xmetricshttp.DefaultCodeLabel,
			xmetricshttp.DefaultMethodLabel,
			ServerLabel,
		),
		xmetrics.ProvideHistogramVec(
			prometheus.HistogramOpts{
				Name: "server_request_duration_ms",
				Help: "tracks incoming request durations in ms",
			},
			xmetricshttp.DefaultCodeLabel,
			xmetricshttp.DefaultMethodLabel,
			ServerLabel,
		),
		xmetrics.ProvideGaugeVec(
			prometheus.GaugeOpts{
				Name: "server_requests_in_flight",
				Help: "tracks the current number of incoming requests being processed",
			},
			ServerLabel,
		),
	)
}