Introduction to URL templating
The Oracle Eloqua app developer framework supports URL Templating to enable you to configure the service URIs that Eloqua calls out to. Any acceptable template parameter is substituted with the appropriate value before the call is made.
Common URL parameters include {UserId}, the unique identifier for the user whose actions triggered the call, {InstanceId}, the GUID-based ID that identifies an instance of a service, and {EventType}, which provides campaign status information (created, activated, draft, and so on). These URL parameters enable you to configure the service URLs that Eloqua calls out to, specifying the information that you need for your application.
Example
Consider this templated URL:
https://awesomeapp.example.com/create/instance={InstanceId}&asset={AssetId}&site={SiteName}
When Eloqua calls the URL, the templated parameters are replaced with the appropriate values:
https://awesomeapp.example.com/create/instance=b5fc25ce-9709-42c4-a57d-caa00e23f658&asset=45&site=DocsExampleSite
Recommendations
Choose the URL parameters to include in your templated URLs based on your use case. These parameters provide contextual information: your application design will determine which parameters you need. The full list of parameters is available. The URL parameters reference provides a description for each parameter. You should familiarize yourself with the supported URL parameters when designing your templated URLs.
The 
service registration guides