What is the purpose of the On Before Request callback in REST?

The On Before Request callback in REST is designed specifically to modify the request before it is sent to an external service. This allows developers to manipulate aspects such as headers, query parameters, or payload contents dynamically based on specific conditions or logic defined within the application. For instance, if you need to include an authorization token or adjust certain data formats based on user input, this callback is the ideal place to implement such changes.

By utilizing this callback, developers can ensure that the request adheres to requirements set by the external service, making it a crucial part of integrating with RESTful APIs effectively. This capability not only promotes flexibility but also enhances control over how requests are structured before they reach the target endpoint.