Cover issues #1, xiaotuanyu120#2 and fix wrong defer

watchdog-tomcat.go

@@ -1,23 +1,24 @@
 package main
-
+ 
 import (
     "bytes"
     "errors"
     "flag"
     "fmt"
     "io"
     "net/http"
+    "crypto/tls"
     "os"
     "os/exec"
     "strconv"
     "strings"
     "sync"
     "syscall"
     "time"
-
+ 
     "github.com/coreos/go-systemd/daemon"
 )
-
+ 
 func runWatchedApp(application string) (pid int, err error) {
     /*Execute Application
       1. run app and set group pid for the forked child process
@@ -32,19 +33,19 @@ func runWatchedApp(application string) (pid int, err error) {
     }
     pgid := cmd.Process.Pid
     cmd.Wait()
-
+ 
     /*Get pid of JVM
       get pid of child process by filter ps result using group pid*/
     grep := exec.Command("grep", strconv.Itoa(pgid))
     ps := exec.Command("ps", "axo", "pid,pgid,comm")
-
+ 
     var out bytes.Buffer
     pr, pw := io.Pipe()
-
+ 
     ps.Stdout = pw
     grep.Stdin = pr
     grep.Stdout = &out
-
+ 
     err = ps.Start()
     if err != nil {
         fmt.Println(err)
@@ -63,35 +64,48 @@ func runWatchedApp(application string) (pid int, err error) {
     }()
     defer pr.Close()
     grep.Wait()
-
+ 
     res := strings.TrimSpace(out.String())
     pid, _ = strconv.Atoi(strings.Split(res, " ")[0])
     return pid, nil
 }
-
+ 
 func healthCheck(check_url string, timeout time.Duration) (bool, error) {
+    tr := &http.Transport{
+        TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
+    }
     var netClient = &http.Client{
+        Transport: tr,
         Timeout: time.Second * timeout,
+        CheckRedirect: func(req *http.Request, via []*http.Request) error {
+            return http.ErrUseLastResponse
+        },
     }
     resp, err := netClient.Get(check_url)
+    if resp != nil {
+        defer resp.Body.Close()
+    }
     if err != nil {
         return false, err
     }
-    if resp.StatusCode != 200 {
-        return false, errors.New("health check status is not 200")
+    if resp.StatusCode == 200  {
+        return true, nil
+    } else if resp.StatusCode >= 300 && resp.StatusCode < 400 {
+        return true, nil
+    } else {
+        return false, errors.New("health check status is not 200 or 3xx")
     }
-    defer resp.Body.Close()
     return true, nil
 }
-
+ 
 func fileExists(filename string) bool {
     info, err := os.Stat(filename)
     if os.IsNotExist(err) {
         return false
     }
     return !info.IsDir()
 }
-
+ 
 func main() {
     // GET ALL FLAGS
     app := flag.String("app", "", "path to the app should be run")
@@ -103,14 +117,14 @@ func main() {
     initialcheck_timeout := flag.Duration("initialcheck-timeout", 5, "Timeout for initialcheck when service is boot up")
     fail_max := flag.Int("fail-max", 20, "max continued failed time")
     flag.Parse()
-
+ 
     if !fileExists(*app) {
         fmt.Printf("app [%s] should exist and is an executable file", app)
         os.Exit(1)
     }
-
+ 
     check_url := fmt.Sprintf("%s://%s:%s/%s", *scheme, *ip, *port, *path)
-
+ 
     // RUN APPLICATION
     pid, err := runWatchedApp(*app)
     if err != nil {
@@ -119,7 +133,7 @@ func main() {
     } else {
         daemon.SdNotify(false, fmt.Sprintf("MAINPID=%d", pid))
     }
-
+ 
     /* WATCHDOG INITIAL
        start watchdog when
        1. first health check success*/
@@ -134,26 +148,26 @@ func main() {
         }
         time.Sleep(1000 * time.Millisecond)
     }
-
+ 
     // WATCHDOG START
     var wg sync.WaitGroup
     wg.Add(1)
     go func(check_url string) {
         watchdog_usec, _ := strconv.ParseFloat(os.Getenv("WATCHDOG_USEC"), 64)
-
+ 
         var wd_fail bool
         var wd_usec, check_time_spent float64
         var wd_interval, continue_fail int
-
+ 
         wd_usec = watchdog_usec / (2 * 1000000)
-
+ 
         for {
             // send watchdog signal
             if wd_fail == false {
                 daemon.SdNotify(false, daemon.SdNotifyWatchdog)
                 fmt.Printf("WATCHDOG STATUS: activate; LAST_CHECK_TIME_SPENT: %f; LAST_SLEEP_TIME: %d\n", check_time_spent, wd_interval)
             }
-
+ 
             // check and change the watchdog failed state
             check_start := time.Now()
             /* add your alert logic here, send alert to email or IM
@@ -171,7 +185,7 @@ func main() {
                 wd_fail = false
             }
             check_time_spent = time.Since(check_start).Seconds()
-
+ 
             if wd_fail == false {
                 if check_success == false {
                     fmt.Printf("CHECK STATUS: failed; ERROR: %s\n", err.Error())
@@ -186,4 +200,4 @@ func main() {
         }
     }(check_url)
     wg.Wait()
-}
+}