Files
remotesupport/check_status.go
2021-12-22 20:15:49 +01:00

137 lines
3.2 KiB
Go

package main
import (
"fmt"
"os"
"net/http"
"time"
"io/ioutil"
"encoding/json"
)
// a struct to hold the result from each request including an index
// which will be used for sorting the results after they come in
type result struct {
id int
status int
err error
}
type check struct {
// defining struct variables
Url string `json:"url"`
Id int `json:"id"`
Computers_id int `json:"computers_id"`
Status string `json:"status"`
}
func boundedParallelGet(Checks []check, concurrencyLimit int) []check {
// this buffered channel will block at the concurrency limit
semaphoreChan := make(chan struct{}, concurrencyLimit)
// this channel will not block and collect the http request results
resultsChan := make(chan *result)
// make sure we close these channels when we're done with them
defer func() {
close(semaphoreChan)
close(resultsChan)
}()
// keen an index and loop through every url we will send a request to
for _,chck := range Checks {
// start a go routine with the index and url in a closure
go func(chck check) {
var status int
// this sends an empty struct into the semaphoreChan which
// is basically saying add one to the limit, but when the
// limit has been reached block until there is room
semaphoreChan <- struct{}{}
// send the request and put the response in a result struct
// along with the index so we can sort them later along with
// any error that might have occoured
//fmt.Println(chck.Url)
client := http.Client{
Timeout: 7 * time.Second,
}
res, err := client.Get(chck.Url)
status = 404
if err == nil {
status = res.StatusCode
}
result := &result{chck.Id, status, err}
// now we can send the result struct through the resultsChan
resultsChan <- result
// once we're done it's we read from the semaphoreChan which
// has the effect of removing one from the limit and allowing
// another goroutine to start
<-semaphoreChan
}(chck)
}
// make a slice to hold the results we're expecting
var results []result
// start listening for any results over the resultsChan
// once we get a result append it to the result slice
for {
result := <-resultsChan
results = append(results, *result)
// if we've reached the expected amount of urls then stop
if len(results) == len(Checks) {
break
}
}
var ret []check
for i := range results {
ch := m[results[i].id]
if results[i].status == 200 {
ch.Status = "OK"
ret = append(ret,*ch)
}
}
// now we're done we return the results
return ret
}
var checks []check
var m = make(map[int]*check)
func init() {
bytes, _ := ioutil.ReadAll(os.Stdin)
json.Unmarshal(bytes , &checks)
for i := range checks {
m[checks[i].Id] = &checks[i]
}
}
func main() {
str_debug := os.Getenv("debug")
str_threads := os.Getenv("threads")
threads, _ := strconv.Atoi(str_threads)
debug, _ := strconv.ParseBool(str_debug)
//startTime := time.Now()
results := boundedParallelGet(checks, threads)
//seconds := time.Since(startTime).Seconds()
//tmplate := "requests: %d/%d in %v"
// fmt.Printf(tmplate, len(results), len(checks), seconds)
val,_ := json.MarshalIndent(results, "", " ")
fmt.Print(string(val))
}