A DataRaptor , now called an OmniStudio Data Mapper , is specifically designed to read, transform, and write data to Salesforce objects. For the use case in this question, the external portal already exists; the primary requirement is therefore to take submitted application data and map it into the corresponding Public Sector Salesforce objects.
Salesforce states that a Data Mapper Load accepts JSON, XML, or supported custom input formats and writes the resulting data to Salesforce objects using configured object and field mappings. More importantly for this scenario, Salesforce exposes a Data Mapper REST API . An external application can POST a JSON payload to a Data Mapper Load, and the Data Mapper updates or creates Salesforce records according to its mappings.
That makes DataRaptor/Data Mapper an appropriate declarative bridge between the existing external portal and Public Sector's Grant application records.
An Integration Procedure is preferred when orchestration involves multiple data sources, several operations, conditional processing, REST integrations, error handling, or multiple Data Mappers. Salesforce recommends a single Data Mapper where the requirement is fundamentally a Salesforce-object write operation that can be handled through direct mappings.
FlexCards provide user-interface presentation. OmniOut runs OmniStudio UI components on third-party sites, but the question states that the agency will retain its existing portal and specifically needs to integrate submitted data .
Study Guide Reference: Public Sector Solution Product Configuration – OmniStudio DataRaptors/Data Mappers; Data Mapper Load; REST API; external application integration.
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