Description

Background jobs, such as publishing, search index updates, and scheduled task processing, might get interrupted by an exception. Consequently, new jobs with the same name cannot be initiated until the application has been restarted.

Examples of exceptions:

Exception: System.AggregateException
Message: One or more exceptions occurred while processing the subscribers to the 'job:starting' event.

Exception: HotChocolate.Subscriptions.InMemory.InvalidMessageTypeException
Message: Exception of type 'HotChocolate.Subscriptions.InMemory.InvalidMessageTypeException' was thrown.

Solution

To mitigate the issue, disable GraphQL Subscription feature by changing the value of the GraphQL.Subscription.Enabled setting to false. The values must be patched by creating a configuration patch in the \App_Config\Include\zzz folder as follows:

<?xml version="1.0" encoding="utf-8" ?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
<sitecore>
<settings>
<setting name="GraphQL.Subscription.Enabled" value="false" />
</settings>
</sitecore>
</configuration>

Note: When the GraphQL Subscription feature is disabled it is not possible to use GraphQL API to subscribe to system events like:

• changes to the publishing status
• job:starting, job:started, job:finished events
• item:created, item:deleted events

The feature is not used out of the box and may be safely disabled when not in use.