Implement If-Match, If-None-Match for DELETE method

crates/carddav/src/address_object/methods.rs

@@ -68,9 +68,6 @@ pub async fn put_object<AS: AddressbookStore>(
         return Err(Error::Unauthorized);
     }
 
-    // TODO: implement If-Match
-    //
-
     let overwrite =
         Some(&HeaderValue::from_static("*")) != req.headers().get(header::IF_NONE_MATCH);
 

crates/carddav/src/address_object/resource.rs

@@ -86,6 +86,10 @@ impl Resource for AddressObjectResource {
         Some(&self.principal)
     }
 
+    fn get_etag(&self) -> Option<String> {
+        Some(self.object.get_etag())
+    }
+
     fn get_user_privileges(&self, user: &User) -> Result<UserPrivilegeSet, Self::Error> {
         Ok(UserPrivilegeSet::owner_only(
             user.is_principal(&self.principal),