From e928c8c103d8f590cdabafbc47f24eab1e9314a9 Mon Sep 17 00:00:00 2001
From: Nick Campbell <nicholas.j.campbell@gmail.com>
Date: Tue, 26 May 2020 22:51:12 -0400
Subject: [PATCH] GH-467 GH-478 GH-469 GH-470 GH-497 GH-498 - Allow soft
 warning when a hard error isn't required.

Signed-off-by: Nick Campbell <nicholas.j.campbell@gmail.com>
---
 README.md   |  5 +++++
 lib/job.js  |  6 ++++--
 lib/time.js | 18 ++++++++++++------
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index c099ed7f..059a9194 100644
--- a/README.md
+++ b/README.md
@@ -158,6 +158,11 @@ Parameter Based
       loop. For more information take a look at
       [timers#timers_timeout_unref](https://nodejs.org/api/timers.html#timers_timeout_unref)
       from the NodeJS docs.
+    - `softTimeout` - [OPTIONAL] - This module needs to determine the time at which to run.
+      However, there have been cases when an infinite loop can occur in this determination.
+      When `true`, the module will display a warning if the time has slipped by more than 5
+      seconds trying to determine the next time to trigger the onTick. When `false`, this
+      will throw an exception stopping the execution.
   - `start` - Runs your job.
   - `stop` - Stops your job.
   - `setTime` - Stops and changes the time for the `CronJob`. Param must be a `CronTime`.
diff --git a/lib/job.js b/lib/job.js
index eb022628..0caa1cc8 100644
--- a/lib/job.js
+++ b/lib/job.js
@@ -33,7 +33,8 @@ function CronJob(CronTime, spawn) {
 		context,
 		runOnInit,
 		utcOffset,
-		unrefTimeout
+		unrefTimeout,
+		softTimeout
 	) {
 		var _cronTime = cronTime;
 		var argCount = 0;
@@ -54,12 +55,13 @@ function CronJob(CronTime, spawn) {
 			_cronTime = cronTime.cronTime;
 			utcOffset = cronTime.utcOffset;
 			unrefTimeout = cronTime.unrefTimeout;
+			softTimeout = cronTime.softTimeout || true; // default to "opt in" soft timeout warning rather than throwing an exception if dwthe detecting a new time slips slightly. this can mean that an "infinite loop" is possible when trying to determine a new date
 		}
 
 		this.context = context || this;
 		this._callbacks = [];
 		this.onComplete = fnWrap(onComplete);
-		this.cronTime = new CronTime(_cronTime, timeZone, utcOffset);
+		this.cronTime = new CronTime(_cronTime, timeZone, utcOffset, softTimeout);
 		this.unrefTimeout = unrefTimeout;
 
 		addCallback.call(this, fnWrap(onTick));
diff --git a/lib/time.js b/lib/time.js
index e09af4b0..38309a5b 100644
--- a/lib/time.js
+++ b/lib/time.js
@@ -66,8 +66,9 @@ const RE_WILDCARDS = /\*/g;
 const RE_RANGE = /^(\d+)(?:-(\d+))?(?:\/(\d+))?$/g;
 
 function CronTime(luxon) {
-	function CT(source, zone, utcOffset) {
+	function CT(source, zone, utcOffset, softTimeout) {
 		this.source = source;
+		this.softTimeout = softTimeout;
 
 		if (zone) {
 			const dt = luxon.DateTime.fromObject({ zone: zone });
@@ -265,13 +266,18 @@ function CronTime(luxon) {
 
 				// hard stop if the current date is after the expected execution
 				if (Date.now() > timeout) {
-					throw new Error(
-						`Something went wrong. cron reached maximum iterations.
+					var msg = `Something went wrong. cron reached maximum iterations.
 							Please open an  issue (https://github.com/kelektiv/node-cron/issues/new) and provide the following string
 							Time Zone: ${zone || '""'} - Cron String: ${this} - UTC offset: ${date.format(
-							'Z'
-						)} - current Date: ${luxon.DateTime.local().toString()}`
-					);
+						'Z'
+					)} - current Date: ${luxon.DateTime.local().toString()}`;
+
+					if (this.softTimeout) {
+						// a soft timeout here could allow for an infinite loop. to prevent this, set the soft timeout to true
+						console.warn(msg);
+					} else {
+						throw new Error(msg);
+					}
 				}
 
 				if (