refactor(ports): CQRS split — UserRepository = UserReader + UserWriter supertrait

crates/domain/src/ports.rs

@@ -45,10 +45,16 @@ pub trait EventConsumer: Send + Sync {
 }
 
 #[async_trait]
-pub trait UserRepository: Send + Sync {
+pub trait UserReader: Send + Sync {
     async fn find_by_id(&self, id: &UserId) -> Result<Option<User>, DomainError>;
     async fn find_by_username(&self, username: &Username) -> Result<Option<User>, DomainError>;
     async fn find_by_email(&self, email: &Email) -> Result<Option<User>, DomainError>;
+    async fn list_with_stats(&self) -> Result<Vec<UserSummary>, DomainError>;
+    async fn count(&self) -> Result<i64, DomainError>;
+}
+
+#[async_trait]
+pub trait UserWriter: Send + Sync {
     async fn save(&self, user: &User) -> Result<(), DomainError>;
     async fn update_profile(
         &self,
@@ -59,10 +65,13 @@ pub trait UserRepository: Send + Sync {
         header_url: Option<String>,
         custom_css: Option<String>,
     ) -> Result<(), DomainError>;
-    async fn list_with_stats(&self) -> Result<Vec<UserSummary>, DomainError>;
-    async fn count(&self) -> Result<i64, DomainError>;
 }
 
+/// Combined supertrait — `AppState.users` stays `Arc<dyn UserRepository>`.
+/// Blanket impl: any type implementing both sub-traits gets `UserRepository` for free.
+pub trait UserRepository: UserReader + UserWriter {}
+impl<T: UserReader + UserWriter> UserRepository for T {}
+
 #[async_trait]
 pub trait ThoughtRepository: Send + Sync {
     async fn save(&self, thought: &Thought) -> Result<(), DomainError>;

crates/domain/src/testing.rs

@@ -45,7 +45,7 @@ pub struct TestStore {
 }
 
 #[async_trait]
-impl UserRepository for TestStore {
+impl UserReader for TestStore {
     async fn find_by_id(&self, id: &UserId) -> Result<Option<User>, DomainError> {
         Ok(self
             .users
@@ -73,6 +73,22 @@ impl UserRepository for TestStore {
             .find(|u| u.email.as_str() == email.as_str())
             .cloned())
     }
+    async fn list_with_stats(&self) -> Result<Vec<UserSummary>, DomainError> {
+        Ok(vec![])
+    }
+    async fn count(&self) -> Result<i64, DomainError> {
+        Ok(self
+            .users
+            .lock()
+            .unwrap()
+            .iter()
+            .filter(|u| u.local)
+            .count() as i64)
+    }
+}
+
+#[async_trait]
+impl UserWriter for TestStore {
     async fn save(&self, user: &User) -> Result<(), DomainError> {
         let mut g = self.users.lock().unwrap();
         g.retain(|u| u.id != user.id);
@@ -103,18 +119,6 @@ impl UserRepository for TestStore {
         }
         Ok(())
     }
-    async fn list_with_stats(&self) -> Result<Vec<UserSummary>, DomainError> {
-        Ok(vec![])
-    }
-    async fn count(&self) -> Result<i64, DomainError> {
-        Ok(self
-            .users
-            .lock()
-            .unwrap()
-            .iter()
-            .filter(|u| u.local)
-            .count() as i64)
-    }
 }
 
 #[async_trait]