HostChecker/main.go

115 lines
2.6 KiB
Go

package main
import "fmt"
import "net/http"
import "io"
import "io/ioutil"
import "log"
import "gopkg.in/yaml.v3"
import "time"
import "sync"
type Check struct {
Type string `yaml:"type"`
Port int `yaml:"port"`
Uri string `yaml:"uri"`
Method string `yaml:"method"`
Timeout int `yaml:"timeout"`
Interval int `yaml:"interval"`
}
type Group struct {
Name string `yaml:"group"`
Tables []string `yaml:"tables"`
Hosts []string `yaml:"hosts"`
Check Check `yaml:"check"`
}
func main() {
log.Println("Starting")
var waitGroup sync.WaitGroup
var conf map[string]Group
yamlFile, err := ioutil.ReadFile("conf.yaml")
if err != nil {
log.Fatalf("Configuration open error #%v ", err)
}
err = yaml.Unmarshal(yamlFile, &conf)
if err != nil {
log.Fatalf("Configuration read error #%v", err)
}
stopChannel := make(chan bool)
for name, group := range conf {
log.Println("Checking group", name, group)
waitGroup.Add(1)
go checkGroup(name, group, &waitGroup, stopChannel)
}
time.Sleep(5 * time.Second)
log.Println("main closing stopChannel")
close(stopChannel)
waitGroup.Wait()
}
func checkGroup(name string, group Group, waitGroup *sync.WaitGroup, stopChannel chan bool) {
channels := make(map[string]chan int)
var checkHostWaitGroup sync.WaitGroup
for _, host := range group.Hosts {
channel := make(chan int, 1)
channels[host] = channel
checkHostWaitGroup.Add(1)
go checkHost(channels[host], name, host, group.Check, &checkHostWaitGroup, stopChannel)
}
for {
select {
case <-stopChannel:
log.Println("checkGroup", name, "stopChannel")
checkHostWaitGroup.Wait()
waitGroup.Done()
return
break
default:
for host, channel := range channels {
select {
case stop := <-stopChannel:
log.Println("checkGroup", name, "stopChannel", stop)
break
case status := <-channel:
log.Println("Status for ", host, "is", status)
default:
time.Sleep(100 * time.Millisecond)
}
}
}
}
}
func checkHost(status chan<- int,group string, host string, check Check, waitGroup *sync.WaitGroup, stopChannel chan bool) {
client := &http.Client{
Timeout: time.Second * time.Duration(check.Timeout),
}
for {
select {
case <-stopChannel:
log.Println("checkHost", host, "group", group, "stopChannel")
waitGroup.Done()
return
default:
resp, err := client.Head(fmt.Sprintf("http://%s", host))
if err != nil {
log.Println(host, "Failed")
status <- 1
} else {
status <- 0
_, _ = io.ReadAll(resp.Body)
resp.Body.Close()
log.Println(host, "Status", resp.StatusCode)
}
time.Sleep(time.Duration(check.Interval) * time.Second)
}
}
}