bring the ffi module to 3.2.x

cedar-policy/CHANGELOG.md

@@ -5,6 +5,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [3.2.0] - upcoming
+
+### Added
+
+- New `ffi` module with an improved FFI interface. This will replace the
+  `frontend` module in the 4.0 release, but is available now for early adopters;
+  the `frontend` module is now deprecated.
+
 ## [3.1.3] - 2024-04-15
 
 ### Changed
@@ -423,7 +431,8 @@ Cedar Language Version: 2.0.0
 Cedar Language Version: 2.0.0
 - Initial release of `cedar-policy`.
 
-[Unreleased]: https://github.com/cedar-policy/cedar/compare/v3.1.3...main
+[Unreleased]: https://github.com/cedar-policy/cedar/compare/v3.2.0...main
+[3.2.0]: https://github.com/cedar-policy/cedar/compare/v3.1.3...v3.2.0
 [3.1.3]: https://github.com/cedar-policy/cedar/compare/v3.1.2...v3.1.3
 [3.1.2]: https://github.com/cedar-policy/cedar/compare/v3.1.1...v3.1.2
 [3.1.1]: https://github.com/cedar-policy/cedar/compare/v3.1.0...v3.1.1

cedar-policy/src/api.rs

@@ -844,9 +844,9 @@ impl From<authorizer::AuthorizationError> for AuthorizationError {
 #[derive(Debug, PartialEq, Eq, Clone)]
 pub struct Response {
     /// Authorization decision
-    decision: Decision,
+    pub(crate) decision: Decision,
     /// Diagnostics providing more information on how this decision was reached
-    diagnostics: Diagnostics,
+    pub(crate) diagnostics: Diagnostics,
 }
 
 /// A partially evaluated authorization response.
@@ -1109,6 +1109,16 @@ impl Diagnostics {
     pub fn errors(&self) -> impl Iterator<Item = &AuthorizationError> + '_ {
         self.errors.iter()
     }
+
+    /// Consume the `Diagnostics`, producing owned versions of `reason()` and `errors()`
+    pub(crate) fn into_components(
+        self,
+    ) -> (
+        impl Iterator<Item = PolicyId>,
+        impl Iterator<Item = AuthorizationError>,
+    ) {
+        (self.reason.into_iter(), self.errors.into_iter())
+    }
 }
 
 impl Response {
@@ -1711,6 +1721,18 @@ impl<'a> ValidationResult<'a> {
                     .map(|w| w as &dyn Diagnostic)
             })
     }
+
+    pub(crate) fn into_errors_and_warnings(
+        self,
+    ) -> (
+        impl Iterator<Item = ValidationError<'static>>,
+        impl Iterator<Item = ValidationWarning<'static>>,
+    ) {
+        (
+            self.validation_errors.into_iter(),
+            self.validation_warnings.into_iter(),
+        )
+    }
 }
 
 impl<'a> From<cedar_policy_validator::ValidationResult<'a>> for ValidationResult<'static> {