Adding ability to pause transcription

app/worker.py

@@ -15,6 +15,30 @@ LIB = Path(os.getenv("LIBRARY_ROOT", "/library"))
 TRN = Path(os.getenv("TRANSCRIPT_ROOT", "/transcripts"))
 TMP = Path(os.getenv("TMP_ROOT", "/tmpdl"))
 
+# --- Runtime pause switch for CPU-heavy work (no rebuild needed) ---
+PAUSE_TRANSCRIBE_FILE = Path(os.getenv("PAUSE_TRANSCRIBE_FILE", str(TRN / ".pause_transcribe")))
+
+def transcribe_paused() -> bool:
+    """Return True if new transcription work should be paused."""
+    try:
+        return PAUSE_TRANSCRIBE_FILE.exists()
+    except Exception:
+        return False
+
+def wait_if_paused(label: str = "transcribe", poll_sec: int = 10):
+    """
+    If the pause file exists, block this worker in a low-CPU sleep loop until it is removed.
+    This lets you 'pause' heavy work without killing workers or rebuilding.
+    """
+    try:
+        if transcribe_paused():
+            print(f"[pause] {label}: pause flag present at {PAUSE_TRANSCRIBE_FILE}; waiting…", flush=True)
+        while transcribe_paused():
+            time.sleep(max(1, int(poll_sec)))
+    except Exception:
+        # If anything goes wrong reading the flag, don't block the pipeline.
+        pass
+
 MODEL_NAME = os.getenv("WHISPER_MODEL","large-v3")
 COMPUTE = os.getenv("WHISPER_PRECISION","int8")
 WHISPER_LANGUAGE = os.getenv("WHISPER_LANGUAGE", "auto").strip()
@@ -1326,6 +1350,7 @@ def _postprocess_after_transcribe(media_path: Path, base: Path):
 
 def transcribe_job(path_str: str):
     """RQ job: heavy transcription only. Safe to import by dotted path 'worker.transcribe_job'."""
+    wait_if_paused("transcribe_job")
     p = Path(path_str)
     base = transcribe(p)
     _postprocess_after_transcribe(p, base)
@@ -1334,6 +1359,8 @@ def transcribe_job(path_str: str):
 def enqueue_transcribe(path: Path) -> bool:
     """Enqueue a transcription job to the 'transcribe' queue. Returns True on success."""
     try:
+        if transcribe_paused():
+            print(f"[queue] pause flag present; enqueuing job for {path} but workers will wait", flush=True)
         conn = Redis.from_url(REDIS_URL)
         q = Queue("transcribe", connection=conn, default_timeout=60*60*24)
         # Use dotted path so workers in other processes can import
@@ -1447,6 +1474,8 @@ def handle_local_file(path_str: str):
                 return
 
         # 2) Otherwise, run transcription (offload to queue if enabled and not in transcribe-only worker)
+        # Respect runtime pause switch before starting heavy work
+        wait_if_paused("handle_local_file")
         if OFFLOAD_TRANSCRIBE and WORKER_MODE != "transcribe" and enqueue_transcribe(p):
             log({**info, **{"status": "queued_transcribe"}})
             return
@@ -1666,6 +1695,8 @@ def handle_url(url: str):
                 if repo_json:
                     base = reuse_repo_transcript(dest, repo_json)
             if not base:
+                # Respect runtime pause switch before starting heavy work
+                wait_if_paused("handle_url")
                 if OFFLOAD_TRANSCRIBE and WORKER_MODE != "transcribe" and enqueue_transcribe(dest):
                     log({**info, **{"status": "queued_transcribe"}})
                     continue