Implement 'inteval' config parameter -> number of seconds between checks

cachet/config.go

@@ -4,13 +4,14 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"github.com/castawaylabs/cachet-monitor/system"
 	"io"
 	"io/ioutil"
 	"log"
 	"net/http"
 	"net/url"
 	"os"
+
+	"github.com/castawaylabs/cachet-monitor/system"
 )
 
 // Static config
@@ -69,6 +70,13 @@ func init() {
 		os.Exit(1)
 	}
 
+	for _, mon := range Config.Monitors {
+		if mon.Interval <= 0 {
+			mon.Interval = 1
+		}
+		mon.stopC = make(chan struct{})
+	}
+
 	if len(systemName) > 0 {
 		Config.SystemName = systemName
 	}

cachet/monitor.go

@@ -19,10 +19,14 @@ type Monitor struct {
 	ComponentID        *int          `json:"component_id"`
 	ExpectedStatusCode int           `json:"expected_status_code"`
 	StrictTLS          *bool         `json:"strict_tls"`
+	Interval           time.Duration `json:"interval"`
 
 	History        []bool    `json:"-"`
 	LastFailReason *string   `json:"-"`
 	Incident       *Incident `json:"-"`
+
+	// Closed when mon.Stop() is called
+	stopC chan struct{} `json:"-"`
 }
 
 // Run loop
@@ -42,6 +46,26 @@ func (monitor *Monitor) Run() {
 	}
 }
 
+func (monitor *Monitor) Stop() {
+	if monitor.Stopped() {
+		return
+	}
+	close(monitor.stopC)
+}
+
+func (monitor *Monitor) StopC() <-chan struct{} {
+	return monitor.stopC
+}
+
+func (monitor *Monitor) Stopped() bool {
+	select {
+	case <-monitor.stopC:
+		return true
+	default:
+		return false
+	}
+}
+
 func (monitor *Monitor) doRequest() bool {
 	client := &http.Client{
 		Timeout: timeout,

main.go

@@ -1,8 +1,12 @@
 package main
 
 import (
-	"github.com/castawaylabs/cachet-monitor/cachet"
+	"os"
+	"os/signal"
+	"sync"
 	"time"
+
+	"github.com/castawaylabs/cachet-monitor/cachet"
 )
 
 func main() {
@@ -20,10 +24,31 @@ func main() {
 
 	log.Println()
 
-	ticker := time.NewTicker(time.Second)
+	wg := &sync.WaitGroup{}
-	for range ticker.C {
 	for _, mon := range config.Monitors {
-			go mon.Run()
+		wg.Add(1)
+		go func(mon *cachet.Monitor) {
+			ticker := time.NewTicker(mon.Interval * time.Second)
+			for {
+				select {
+				case <-ticker.C:
+					mon.Run()
+				case <-mon.StopC():
+					wg.Done()
+					return
 				}
 			}
+		}(mon)
+	}
+
+	signals := make(chan os.Signal, 1)
+	signal.Notify(signals, os.Interrupt, os.Kill)
+	<-signals
+
+	log.Println("Waiting monitors to end current operation")
+	for _, mon := range config.Monitors {
+		mon.Stop()
+	}
+
+	wg.Wait()
 }