The error message “System.CalloutException: Callout from scheduled Apex not supported” in Salesforce indicates an attempt to make external service callouts directly from scheduled Apex, which is forbidden due to resource consumption concerns. To address this, a workaround involves leveraging asynchronous Apex, such as Queueable Apex or Batch Apex, to perform callouts asynchronously. In this approach, the scheduled Apex class enqueues a separate asynchronous job responsible for executing the callout.
By decoupling the callout from the scheduled job, it avoids violating Salesforce’s limitations while still achieving the desired functionality. This strategy ensures efficient resource management and prevents potential performance issues associated with synchronous callouts from scheduled Apex. Effective error handling and retry mechanisms should be implemented to maintain the reliability of the integration with external services.
