feat: Implement batch cancellation for audiobook processing with enhanced frontend progress display.

qwen3-tts-backend/core/audiobook_service.py

@@ -14,6 +14,17 @@ from db.models import AudiobookProject, AudiobookCharacter, User
 
 logger = logging.getLogger(__name__)
 
+# Cancellation events for batch operations, keyed by project_id
+_cancel_events: dict[int, asyncio.Event] = {}
+
+
+def cancel_batch(project_id: int) -> None:
+    """Signal cancellation for any running batch operation on this project."""
+    ev = _cancel_events.get(project_id)
+    if ev:
+        ev.set()
+        logger.info(f"cancel_batch: project={project_id} cancellation signalled")
+
 
 def _get_llm_service(user: User) -> LLMService:
     from core.security import decrypt_api_key
@@ -570,12 +581,19 @@ async def parse_all_chapters(project_id: int, user: User, db: Session) -> None:
     if not pending:
         return
 
+    cancel_ev = asyncio.Event()
+    _cancel_events[project_id] = cancel_ev
+
     max_concurrent = settings.AUDIOBOOK_PARSE_CONCURRENCY
     semaphore = asyncio.Semaphore(max_concurrent)
     logger.info(f"parse_all_chapters: project={project_id}, {len(pending)} chapters, concurrency={max_concurrent}")
 
     async def parse_with_limit(chapter):
+        if cancel_ev.is_set():
+            return
         async with semaphore:
+            if cancel_ev.is_set():
+                return
             task_db = SessionLocal()
             try:
                 db_user = crud.get_user_by_id(task_db, user.id)
@@ -586,7 +604,8 @@ async def parse_all_chapters(project_id: int, user: User, db: Session) -> None:
                 task_db.close()
 
     await asyncio.gather(*[parse_with_limit(ch) for ch in pending])
-    logger.info(f"parse_all_chapters: project={project_id} complete")
+    _cancel_events.pop(project_id, None)
+    logger.info(f"parse_all_chapters: project={project_id} {'cancelled' if cancel_ev.is_set() else 'complete'}")
 
 
 async def generate_all_chapters(project_id: int, user: User, db: Session) -> None:
@@ -598,6 +617,11 @@ async def generate_all_chapters(project_id: int, user: User, db: Session) -> Non
     if not ready:
         return
 
+    cancel_ev = _cancel_events.get(project_id)
+    if not cancel_ev:
+        cancel_ev = asyncio.Event()
+        _cancel_events[project_id] = cancel_ev
+
     crud.update_audiobook_project_status(db, project_id, "generating")
 
     max_concurrent = settings.AUDIOBOOK_GENERATE_CONCURRENCY
@@ -605,7 +629,11 @@ async def generate_all_chapters(project_id: int, user: User, db: Session) -> Non
     logger.info(f"generate_all_chapters: project={project_id}, {len(ready)} chapters, concurrency={max_concurrent}")
 
     async def generate_with_limit(chapter):
+        if cancel_ev.is_set():
+            return
         async with semaphore:
+            if cancel_ev.is_set():
+                return
             task_db = SessionLocal()
             try:
                 db_user = crud.get_user_by_id(task_db, user.id)
@@ -629,7 +657,8 @@ async def generate_all_chapters(project_id: int, user: User, db: Session) -> Non
     finally:
         final_db.close()
 
-    logger.info(f"generate_all_chapters: project={project_id} complete")
+    _cancel_events.pop(project_id, None)
+    logger.info(f"generate_all_chapters: project={project_id} {'cancelled' if cancel_ev.is_set() else 'complete'}")
 
 
 async def process_all(project_id: int, user: User, db: Session) -> None: