Briefly, this error occurs when Elasticsearch is unable to parse the cron schedule because it can’t find a valid cron expression in the cron array. This usually happens when the cron expression is missing or incorrectly formatted. To resolve this issue, you can: 1) Ensure that a valid cron expression is provided in the cron array. 2) Check the syntax of the cron expression to ensure it’s correctly formatted. 3) If the cron array is empty, add a valid cron expression to it.
This guide will help you check for common problems that cause the log ” could not parse [cron] schedule. no cron expression found in cron array ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: plugin.
Log Context
Log “could not parse [cron] schedule. no cron expression found in cron array” class name is CronSchedule.java. We extracted the following from Elasticsearch source code for those seeking an in-depth context :
"could not parse [cron] schedule. expected a string value in the cron " + "array but found [" + token + "]"
);
}
}
if (crons.isEmpty()) {
throw new ElasticsearchParseException("could not parse [cron] schedule. no cron expression found in cron array");
}
try {
return new CronSchedule(crons.toArray(String[]::new));
} catch (IllegalArgumentException iae) {
throw new ElasticsearchParseException("could not parse [cron] schedule"; iae);
