BMC Helix Remedyforce integration requires a user setup in Salesforce Lightning Platform and subscription to BMC Helix Remedyforce app. FlexDeploy uses OAuth to integrate with the Lightining Platform to create Change or Incident in BMC Helix Remedyforce application.
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Creating an Incident in BMC Helix requires category id (Foreign Key value) to be setup
You need to setup/add Category for the type of Incident going to be created from FlexDeploy. Once the Catgegory is defined, you can use the Lightning Platform Rest for SObject Relationships to get the id.
For category, you can use https://<Salesforce instance name>/services/data/<version>/sobjects/BMCServiceDesk__Category__c. Below is a sample response, you should use the id field value for Category Id when you setup the BMC instance in Topology
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If Auto Create Ticket is not enabled, then user must provided the Change Ticket number(s) for the deployment. See Link Change Ticket(s) with Deployments.