feat: impl TryFrom<AttributeTypeAndValue> for LocalName

Author: bitfl0wer

src/types/federation_id.rs

@@ -262,19 +262,13 @@ mod test {
             oid: OID_RDN_UID,
             value: Any::encode_from(&directory_string).unwrap(),
         };
-        // Ok so this works! that means, that we can convert a directorystring into a Rust string, because Rust strings are utf8
-        // I think we should test this with the other types of DirectoryString, and then finish the
-        // conversion
         assert!(FederationId::try_from(attribute_and_value).is_ok());
 
         let directory_string = DirectoryString::Utf8String(String::from("input@in.put"));
         let attribute_and_value = AttributeTypeAndValue {
             oid: OID_RDN_UID,
             value: Any::encode_from(&directory_string).unwrap(),
         };
-        // Ok so this works! that means, that we can convert a directorystring into a Rust string, because Rust strings are utf8
-        // I think we should test this with the other types of DirectoryString, and then finish the
-        // conversion
         assert!(FederationId::try_from(attribute_and_value).is_err())
     }
 }

src/types/local_name.rs

@@ -1,7 +1,9 @@
 use std::str::FromStr;
 
-use crate::Constrained;
+use x509_cert::attr::AttributeTypeAndValue;
+
 use crate::errors::ConstraintError;
+use crate::{Constrained, OID_RDN_COMMON_NAME};
 
 /// Rust-flavor regular expression describing valid format for the local name of a Federation ID.
 pub const REGEX_LOCAL_NAME: &str = r#"\b([a-z0-9._%+-]+)$"#;
@@ -32,3 +34,46 @@ impl FromStr for LocalName {
         LocalName::new(s)
     }
 }
+
+impl TryFrom<AttributeTypeAndValue> for LocalName {
+    type Error = ConstraintError;
+
+    fn try_from(value: AttributeTypeAndValue) -> Result<Self, Self::Error> {
+        if value.oid != OID_RDN_COMMON_NAME {
+            return Err(crate::errors::InvalidInput::Malformed(format!(
+                "This value has OID {}, which does not match OID {OID_RDN_COMMON_NAME}",
+                value.oid
+            ))
+            .into());
+        }
+        let attribute_value = value.value.value();
+        let string = String::from_utf8_lossy(attribute_value);
+        Self::new(&string)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use der::Any;
+    use x509_cert::ext::pkix::name::DirectoryString;
+
+    use super::*;
+
+    #[test]
+    #[allow(clippy::unwrap_used)]
+    fn from_attribute_type_and_value() {
+        let directory_string = DirectoryString::Utf8String(String::from("input"));
+        let attribute_and_value = AttributeTypeAndValue {
+            oid: OID_RDN_COMMON_NAME,
+            value: Any::encode_from(&directory_string).unwrap(),
+        };
+        assert!(LocalName::try_from(attribute_and_value).is_ok());
+
+        let directory_string = DirectoryString::Utf8String(String::from("input"));
+        let attribute_and_value = AttributeTypeAndValue {
+            oid: OID_RDN_COMMON_NAME,
+            value: Any::encode_from(&directory_string).unwrap(),
+        };
+        assert!(LocalName::try_from(attribute_and_value).is_err())
+    }
+}