feat: implement FromRef for SecurityScheme (#221)

Co-authored-by: Rob Ede <[email protected]>

Author: LucasPickering

crates/oas3/CHANGELOG.md

@@ -5,6 +5,7 @@
 - Document compatibility with OAS v3.1.1.
 - Remove non-spec-compliant `spec::Header::allow_empty_value` field.
 - Minimum supported Rust version (MSRV) is now 1.80.
+- Implement `FromRef` for `spec::SecurityScheme`
 
 ## 0.16.1
 

crates/oas3/src/spec/security_scheme.rs

@@ -1,6 +1,10 @@
 use serde::{Deserialize, Serialize};
 
 use super::Flows;
+use crate::{
+    spec::{FromRef, Ref, RefError, RefType},
+    Spec,
+};
 
 /// Defines a security scheme that can be used by the operations.
 ///
@@ -101,6 +105,22 @@ pub enum SecurityScheme {
     },
 }
 
+impl FromRef for SecurityScheme {
+    fn from_ref(spec: &Spec, path: &str) -> Result<Self, RefError> {
+        let refpath = path.parse::<Ref>()?;
+
+        match refpath.kind {
+            RefType::SecurityScheme => spec
+                .components
+                .as_ref()
+                .and_then(|cs| cs.security_schemes.get(&refpath.name))
+                .ok_or_else(|| RefError::Unresolvable(path.to_owned()))
+                .and_then(|oor| oor.resolve(spec)),
+            typ => Err(RefError::MismatchedType(typ, RefType::SecurityScheme)),
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use url::Url;