feat: chat sessions count

src/backend/backend.did

@@ -44,4 +44,6 @@ type StreamingStrategy = variant {
 service : {
     http_request : (request : HttpRequest) -> (HttpResponse) query;
     http_request_update : (request : HttpUpdateRequest) -> (HttpResponse);
+
+    get_chat_sessions_count : () -> (nat32) query;
 };

src/backend/src/controllers/chat_session.rs

@@ -0,0 +1,55 @@
+use candid::Principal;
+use ic_cdk::{caller, query};
+
+use crate::{
+    repositories::{ChatSessionRepositoryImpl, FilesystemRepositoryImpl},
+    services::{
+        AdminService, AdminServiceImpl, ChatSessionService, ChatSessionServiceImpl,
+        FilesystemServiceImpl,
+    },
+};
+
+#[query]
+fn get_chat_sessions_count() -> u32 {
+    let calling_principal = caller();
+
+    ChatSessionController::default().get_chat_sessions_count(calling_principal)
+}
+
+struct ChatSessionController<A: AdminService, C: ChatSessionService> {
+    admin_service: A,
+    chat_session_service: C,
+}
+
+impl Default
+    for ChatSessionController<
+        AdminServiceImpl,
+        ChatSessionServiceImpl<
+            ChatSessionRepositoryImpl,
+            FilesystemServiceImpl<FilesystemRepositoryImpl>,
+        >,
+    >
+{
+    fn default() -> Self {
+        Self::new(
+            AdminServiceImpl::default(),
+            ChatSessionServiceImpl::default(),
+        )
+    }
+}
+
+impl<A: AdminService, C: ChatSessionService> ChatSessionController<A, C> {
+    fn new(admin_service: A, chat_session_service: C) -> Self {
+        Self {
+            admin_service,
+            chat_session_service,
+        }
+    }
+
+    fn get_chat_sessions_count(&self, calling_principal: Principal) -> u32 {
+        self.admin_service
+            .asset_caller_is_controller(&calling_principal);
+
+        self.chat_session_service.get_chat_sessions_count()
+    }
+}

src/backend/src/controllers/mod.rs

@@ -1 +1,2 @@
+mod chat_session;
 mod http;

src/backend/src/repositories/chat_session_repository.rs

@@ -6,6 +6,8 @@ pub trait ChatSessionRepository {
     fn get_chat_session_by_chat_id(&self, chat_id: &ChatId) -> Option<ChatSession>;
 
     fn set_chat_session_by_chat_id(&self, chat_id: ChatId, chat_session: ChatSession);
+
+    fn get_chat_session_count(&self) -> u64;
 }
 
 pub struct ChatSessionRepositoryImpl {}
@@ -24,6 +26,10 @@ impl ChatSessionRepository for ChatSessionRepositoryImpl {
     fn set_chat_session_by_chat_id(&self, chat_id: ChatId, chat_session: ChatSession) {
         STATE.with_borrow_mut(|s| s.chat_session.insert(chat_id, chat_session));
     }
+
+    fn get_chat_session_count(&self) -> u64 {
+        STATE.with_borrow(|s| s.chat_session.len())
+    }
 }
 
 impl ChatSessionRepositoryImpl {

src/backend/src/services/admin_service.rs

@@ -0,0 +1,28 @@
+use candid::Principal;
+use ic_cdk::{api::is_controller, trap};
+
+pub trait AdminService {
+    fn asset_caller_is_controller(&self, calling_principal: &Principal);
+}
+
+pub struct AdminServiceImpl {}
+
+impl Default for AdminServiceImpl {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl AdminService for AdminServiceImpl {
+    fn asset_caller_is_controller(&self, calling_principal: &Principal) {
+        if !is_controller(calling_principal) {
+            trap("caller is not a controller");
+        }
+    }
+}
+
+impl AdminServiceImpl {
+    fn new() -> Self {
+        Self {}
+    }
+}

src/backend/src/services/chat_session_service.rs

@@ -29,6 +29,8 @@ pub trait ChatSessionService {
 
     fn update_chat_session(&self, chat_id: ChatId, chat_session: ChatSession);
 
+    fn get_chat_sessions_count(&self) -> u32;
+
     fn handle_update_content_message(
         &self,
         chat_id: ChatId,
@@ -84,6 +86,10 @@ impl<T: ChatSessionRepository, F: FilesystemService> ChatSessionService
             .set_chat_session_by_chat_id(chat_id, chat_session);
     }
 
+    fn get_chat_sessions_count(&self) -> u32 {
+        self.chat_session_repository.get_chat_session_count() as u32
+    }
+
     fn handle_update_content_message(
         &self,
         chat_id: ChatId,

src/backend/src/services/mod.rs

@@ -1,5 +1,7 @@
+mod admin_service;
 mod chat_session_service;
 mod filesystem_service;
 
+pub use admin_service::*;
 pub use chat_session_service::*;
 pub use filesystem_service::*;