Update to allow QuitWithoutEnvoyTimeout to be set and take precendenc…

…e over WaitForEnvoyTimeout (#41)

README.md

@@ -18,10 +18,10 @@ When the application exits, unless `NEVER_KILL_ISTIO_ON_FAILURE` has been set an
 | `NEVER_KILL_ISTIO_ON_FAILURE` | If provided and set to `true`, `scuttle` will not instruct istio to exit if the main binary has exited with a non-zero exit code.
 | `SCUTTLE_LOGGING`             | If provided and set to `true`, `scuttle` will log various steps to the console which is helpful for debugging |
 | `START_WITHOUT_ENVOY`         | If provided and set to `true`, `scuttle` will not wait for envoy to be LIVE before starting the main application. However, it will still instruct envoy to exit.|
-| `WAIT_FOR_ENVOY_TIMEOUT`      | If provided and set to a valid `time.Duration` string greater than 0 seconds, `scuttle` will wait for that amount of time before starting the main application. By default, it will wait indefinitely.|
+| `WAIT_FOR_ENVOY_TIMEOUT`      | If provided and set to a valid `time.Duration` string greater than 0 seconds, `scuttle` will wait for that amount of time before starting the main application. By default, it will wait indefinitely. If `QUIT_WITHOUT_ENVOY_TIMEOUT` is set as well, it will take precedence over this variable |
 | `ISTIO_QUIT_API`              | If provided `scuttle` will send a POST to `/quitquitquit` at the given API.  Should be in format `http://127.0.0.1:15020`.  This is intended for Istio v1.3 and higher.  When not given, Istio will be stopped using a `pkill` command.
 | `GENERIC_QUIT_ENDPOINTS`      | If provided `scuttle` will send a POST to the URL given.  Multiple URLs are supported and must be provided as a CSV string.  Should be in format `http://myendpoint.com` or `http://myendpoint.com,https://myotherendpoint.com`.  The status code response is logged (if logging is enabled) but is not used.  A 200 is treated the same as a 404 or 500. `GENERIC_QUIT_ENDPOINTS` is handled before Istio is stopped. |
-| `QUIT_WITHOUT_ENVOY_TIMEOUT`  | If provided and set to a valid duration, `scuttle` will exit if Envoy does not become available before the end of the timeout. If `START_WITHOUT_ENVOY` is also set, this variable will not be taken into account |
+| `QUIT_WITHOUT_ENVOY_TIMEOUT`  | If provided and set to a valid duration, `scuttle` will exit if Envoy does not become available before the end of the timeout and not continue with the passed in executable. If `START_WITHOUT_ENVOY` is also set, this variable will not be taken into account. Also, if `WAIT_FOR_ENVOY_TIMEOUT` is set, this variable will take precedence. |
 
 ## How Scuttle stops Istio
 

main.go

@@ -49,8 +49,11 @@ func main() {
 			err := blockingCtx.Err()
 			if err == nil || errors.Is(err, context.Canceled) {
 				log("Blocking finished, Envoy has started")
+			} else if errors.Is(err, context.DeadlineExceeded) && config.QuitWithoutEnvoyTimeout > time.Duration(0) {
+				log("Blocking timeout reached and Envoy has not started, exiting scuttle")
+				os.Exit(1)
 			} else if errors.Is(err, context.DeadlineExceeded) {
-				log("Blocking timeout reached and Envoy has not started")
+				log("Blocking timeout reached and Envoy has not started, continuing with passed in executable")
 			} else {
 				panic(err.Error())
 			}
@@ -183,7 +186,9 @@ func waitForEnvoy() context.Context {
 	}
 	var blockingCtx context.Context
 	var cancel context.CancelFunc
-	if config.WaitForEnvoyTimeout > time.Duration(0) {
+	if config.QuitWithoutEnvoyTimeout > time.Duration(0) {
+		blockingCtx, cancel = context.WithTimeout(context.Background(), config.QuitWithoutEnvoyTimeout)
+	} else if config.WaitForEnvoyTimeout > time.Duration(0) {
 		blockingCtx, cancel = context.WithTimeout(context.Background(), config.WaitForEnvoyTimeout)
 	} else {
 		blockingCtx, cancel = context.WithCancel(context.Background())
@@ -201,6 +206,10 @@ func pollEnvoy(ctx context.Context, cancel context.CancelFunc) {
 	// We wait forever for envoy to start. In practice k8s will kill the pod if we take too long.
 	b.MaxElapsedTime = config.WaitForEnvoyTimeout
 
+	if config.QuitWithoutEnvoyTimeout > time.Duration(0) {
+		b.MaxElapsedTime = config.QuitWithoutEnvoyTimeout
+	}
+
 	_ = backoff.Retry(func() error {
 		pollCount++
 		rsp := typhon.NewRequest(ctx, "GET", url, nil).Send().Response()

main_test.go

@@ -146,6 +146,7 @@ func TestWaitTillTimeoutForEnvoy(t *testing.T) {
 	fmt.Println("Starting TestWaitTillTimeoutForEnvoy")
 	os.Setenv("QUIT_WITHOUT_ENVOY_TIMEOUT", "500ms")
 	os.Setenv("ENVOY_ADMIN_API", badServer.URL)
+	initTestingEnv()
 	dur, _ := time.ParseDuration("500ms")
 	config.QuitWithoutEnvoyTimeout = dur
 	blockingCtx := waitForEnvoy()
@@ -156,13 +157,13 @@ func TestWaitTillTimeoutForEnvoy(t *testing.T) {
 	case <-time.After(1 * time.Second):
 		t.Fatal("Context did not timeout")
 	case <-blockingCtx.Done():
-		if !errors.Is(blockingCtx.Err(), context.Canceled) {
+		if !errors.Is(blockingCtx.Err(), context.DeadlineExceeded) {
 			t.Fatalf("Context contains wrong error: %s", blockingCtx.Err())
 		}
 	}
 }
 
-// Tests scuttle will continue after WAIT_FOR_ENVOY_TIMEOUT expires and enovy is not ready
+// Tests scuttle will continue after WAIT_FOR_ENVOY_TIMEOUT expires and envoy is not ready
 func TestWaitForEnvoyTimeoutContinueWithoutEnvoy(t *testing.T) {
 	fmt.Println("Starting TestWaitForEnvoyTimeoutContinueWithoutEnvoy")
 	os.Setenv("WAIT_FOR_ENVOY_TIMEOUT", "5s")
@@ -173,7 +174,7 @@ func TestWaitForEnvoyTimeoutContinueWithoutEnvoy(t *testing.T) {
 	err := blockingCtx.Err()
 	if err == nil || !errors.Is(err, context.DeadlineExceeded) {
 		fmt.Println("TestWaitForEnvoyTimeoutContinueWithoutEnvoy err", err)
-		// Err is nil (enovy is up)
+		// Err is nil (envoy is up)
 		// or Err is set, but is not a cancellation err
 		// we expect a cancellation when the time is up
 		t.Fail()