minitor-go/metrics.go

105 lines
2.7 KiB
Go

package main
import (
"fmt"
"net/http"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
)
// TODO: Not sure if this is the best way to handle. A global instance for
// metrics isn't bad, but it might be nice to curry versions of the metrics
// for each monitor. Especially since every monitor has it's own. Perhaps
// another new function that essentially curries each metric for a given
// monitor name would do. This could be run when validating monitors and
// initializing alert templates.
// MinitorMetrics contains all counters and metrics that Minitor will need to access
type MinitorMetrics struct {
alertCount *prometheus.CounterVec
checkCount *prometheus.CounterVec
monitorStatus *prometheus.GaugeVec
}
// NewMetrics creates and initializes all metrics
func NewMetrics() *MinitorMetrics {
// Initialize all metrics
metrics := &MinitorMetrics{
alertCount: prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "minitor_alert_total",
Help: "Number of Minitor alerts",
},
[]string{"alert", "monitor"},
),
checkCount: prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "minitor_check_total",
Help: "Number of Minitor checks",
},
[]string{"monitor", "status", "is_alert"},
),
monitorStatus: prometheus.NewGaugeVec(
prometheus.GaugeOpts{
Name: "minitor_monitor_up_count",
Help: "Status of currently responsive monitors",
},
[]string{"monitor"},
),
}
// Register newly created metrics
prometheus.MustRegister(metrics.alertCount)
prometheus.MustRegister(metrics.checkCount)
prometheus.MustRegister(metrics.monitorStatus)
return metrics
}
// SetMonitorStatus sets the current status of Monitor
func (metrics *MinitorMetrics) SetMonitorStatus(monitor string, isUp bool) {
val := 0.0
if isUp {
val = 1.0
}
metrics.monitorStatus.With(prometheus.Labels{"monitor": monitor}).Set(val)
}
// CountCheck counts the result of a particular Monitor check
func (metrics *MinitorMetrics) CountCheck(monitor string, isSuccess bool, isAlert bool) {
status := "failure"
if isSuccess {
status = "success"
}
alertVal := "false"
if isAlert {
alertVal = "true"
}
metrics.checkCount.With(
prometheus.Labels{"monitor": monitor, "status": status, "is_alert": alertVal},
).Inc()
}
// CountAlert counts an alert
func (metrics *MinitorMetrics) CountAlert(monitor string, alert string) {
metrics.alertCount.With(
prometheus.Labels{
"alert": alert,
"monitor": monitor,
},
).Inc()
}
// ServeMetrics starts an http server with a Prometheus metrics handler
func ServeMetrics() {
http.Handle("/metrics", promhttp.Handler())
host := fmt.Sprintf(":%d", MetricsPort)
_ = http.ListenAndServe(host, nil)
}