Unify the signature of PolicySet::annotation and PolicySet::template_annotation

cedar-policy-core/src/ast/policy_set.rs

@@ -457,11 +457,16 @@ impl PolicySet {
         self.templates.is_empty() && self.links.is_empty()
     }
 
-    /// Lookup a template by policy id
+    /// Lookup a template by policy id, returns [`Option<Arc<Template>>`]
     pub fn get_template(&self, id: &PolicyID) -> Option<Arc<Template>> {
         self.templates.get(id).cloned()
     }
 
+    /// Lookup a template by policy id, returns [`Option<&Template>`]
+    pub fn get_template_ref(&self, id: &PolicyID) -> Option<&Template> {
+        self.templates.get(id).map(AsRef::as_ref)
+    }
+
     /// Lookup an policy by policy id
     pub fn get(&self, id: &PolicyID) -> Option<&Policy> {
         self.links.get(id)

cedar-policy/src/api.rs

@@ -1913,23 +1913,19 @@ impl PolicySet {
     }
 
     /// Extract annotation data from a `Policy` by its `PolicyId` and annotation key
-    pub fn annotation<'a>(&'a self, id: &PolicyId, key: impl AsRef<str>) -> Option<&'a str> {
+    pub fn annotation(&self, id: &PolicyId, key: impl AsRef<str>) -> Option<&str> {
         self.ast
             .get(id.as_ref())?
             .annotation(&key.as_ref().parse().ok()?)
             .map(AsRef::as_ref)
     }
 
     /// Extract annotation data from a `Template` by its `PolicyId` and annotation key.
-    //
-    // TODO: unfortunate that this method returns `Option<String>` and the corresponding method
-    // for policies (`.annotation()`) above returns `Option<&str>`, but this can't be changed
-    // without a semver break
-    pub fn template_annotation(&self, id: &PolicyId, key: impl AsRef<str>) -> Option<String> {
+    pub fn template_annotation(&self, id: &PolicyId, key: impl AsRef<str>) -> Option<&str> {
         self.ast
-            .get_template(id.as_ref())?
+            .get_template_ref(id.as_ref())?
             .annotation(&key.as_ref().parse().ok()?)
-            .map(|annot| annot.val.to_string())
+            .map(AsRef::as_ref)
     }
 
     /// Returns true iff the `PolicySet` is empty

cedar-policy/tests/public_interface.rs

@@ -411,7 +411,7 @@ fn policy_annotations() {
     assert_eq!(s.annotation(&pid, "anno"), Some("good annotation"));
     assert_eq!(
         s.template_annotation(&tid, "tanno"),
-        Some("good annotation".to_string())
+        Some("good annotation")
     );
 }