fix: remove aggressive OBS kill behaviour

Checks for existing OBS process, and tries to connect to that

README.md

@@ -6,3 +6,9 @@ rewind is a lightweight, disk-backed replay recording tool for OBS that continuo
 2) Enable OBS websocket and take note of the host, port and password
 3) Setup config.toml with host, port, password info
 4) Run the daemon as a background service (rewind-daemon)
+
+# Why OBS?
+Instead of implementing a custom screen recorder, rewind uses OBS as the backend recorder. Rationale:
+  - Cross-platform video capture is complex (platform APIs, drivers, hardware acceleration, A/V sync).
+  - Implementing a custom recorder is out of scope and would duplicate mature functionality.
+  - OBS provides a stable, production-grade capture and segmentation pipeline.

rewind/core.py

@@ -2,9 +2,8 @@
 import os
 import datetime
 import subprocess
-import json
 
-from rewind.state import load_state
+from rewind.state import load_state, add_marker_to_state, remove_marker_from_state
 from rewind.paths import load_config
 from tqdm import tqdm
 
@@ -52,34 +51,11 @@ def mark(name: str) -> None:
     if not name:
         raise ValueError("Marker name cannot be empty")
     
-    if marker_exists(name):
-        raise ValueError("Marker name already exists")
-    
-    # writes marker to json file (not state)
-    markers_file = os.path.join(os.path.dirname(__file__), "markers.json")
-    if os.path.exists(markers_file):
-        with open(markers_file, "r") as f:
-            markers = json.load(f)
-    else:
-        markers = []
-
-    markers.append({
-        "name": name,
-        "timestamp": datetime.datetime.now().timestamp()
-    })
-
-    with open(markers_file, "w") as f:
-        json.dump(markers, f, indent=4)
-
+    add_marker_to_state(name)
     print(f"Added marker: {name}")
 
 def get_marker_timestamp(name: str) -> float:
-    markers_file = os.path.join(os.path.dirname(__file__), "markers.json")
-    if not os.path.exists(markers_file):
-        raise RuntimeError("No markers found")
-
-    with open(markers_file, "r") as f:
-        markers = json.load(f)
+    markers = load_state().get("markers", [])
 
     for marker in markers:
         if marker["name"] == name:
@@ -88,40 +64,21 @@ def get_marker_timestamp(name: str) -> float:
     raise ValueError("Marker name does not exist")
 
 def print_markers() -> None:
-    markers_file = os.path.join(os.path.dirname(__file__), "markers.json")
-    if not os.path.exists(markers_file):
-        print("No markers found.")
-        return
+    markers = load_state().get("markers", [])
 
-    with open(markers_file, "r") as f:
-        markers = json.load(f)
+    if markers == []:
+        print("No markers exist.")
 
     for marker in markers:
         format_time = datetime.datetime.fromtimestamp(marker['timestamp']).strftime('%Y-%m-%d %H:%M:%S')
         print(f"{format_time} -> {marker['name']}")
         
 def remove_marker(name: str) -> None:
-    markers_file = os.path.join(os.path.dirname(__file__), "markers.json")
-    if not os.path.exists(markers_file):
-        raise RuntimeError("No markers found")
-
-    with open(markers_file, "r") as f:
-        markers = json.load(f)
-
-    markers = [m for m in markers if m["name"] != name]
-
-    with open(markers_file, "w") as f:
-        json.dump(markers, f, indent=4)
-
+    remove_marker_from_state(name)
     print(f"Removed marker: {name}")
 
 def marker_exists(name: str) -> bool:
-    markers_file = os.path.join(os.path.dirname(__file__), "markers.json")
-    if not os.path.exists(markers_file):
-        return False
-
-    with open(markers_file, "r") as f:
-        markers = json.load(f)
+    markers = load_state().get("markers", [])
 
     for marker in markers:
         if marker["name"] == name:

rewind/daemon.py

@@ -5,16 +5,15 @@ import time
 import obsws_python as obs
 import subprocess
 import logging
-import json
 import shutil
+import signal
 
 from watchdog.observers import Observer
 from watchdog.events import FileSystemEventHandler
 from rewind.paths import load_config
 from rewind.core import mark, marker_exists, remove_marker
-from rewind.state import add_file_to_state, create_state_file_if_needed, cleanup_state_files
+from rewind.state import add_file_to_state, create_state_file_if_needed, cleanup_state
 
-INTERVAL = 10
 running = True
 
 logger = logging.getLogger(__name__)
@@ -22,14 +21,19 @@ logger.setLevel(logging.DEBUG)
 logging.basicConfig(format="%(levelname)s:%(name)s:%(message)s")
 logging.getLogger("obsws_python").setLevel(logging.CRITICAL)
 
+INTERVAL = 10
 SENTINEL_FILE = os.path.expanduser("~/.config/obs-studio/.sentinel")
 OBS_MAX_RETRIES = 10
 
-def open_obs():
-    kill_command = subprocess.run(['pkill', 'obs'])
-    if kill_command.returncode not in [0, 1]:
-        raise SystemError("Could not kill existing OBS instance")
+def shutdown(signum, frame):
+    global running
+    logger.info(f"Received signal {signum}, shutting down cleanly")
+    running = False
 
+signal.signal(signal.SIGINT, shutdown)
+signal.signal(signal.SIGTERM, shutdown)
+
+def clean_obs_sentinel_files():
     if os.path.exists(SENTINEL_FILE):
         try:
             shutil.rmtree(SENTINEL_FILE)
@@ -37,6 +41,14 @@ def open_obs():
         except Exception as e:
             logger.error(f"Could not delete OBS .sentinel directory: {e}")
 
+def is_obs_running():
+    result = subprocess.run(
+        ["pgrep", "-x", "obs"],
+        stdout=subprocess.PIPE
+    )
+    return result.returncode == 0
+
+def open_obs():
     # Using and not checking OBS since it needs to be non-blocking
     subprocess.Popen(["obs", "--minimize-to-tray"], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
 
@@ -49,6 +61,8 @@ def open_obs_connection(host: str, port: int, password: str) -> obs.ReqClient:
             con = obs.ReqClient(host=host, port=port, password=password)
         except ConnectionRefusedError:
             logger.info("OBS WebSocket not ready, retrying...")
+        except obs.events.OBSSDKError:
+            raise RuntimeError("Check OBS credentials")
             
         if con:
             logger.info(f"Successfully connected to OBS at {host}:{port}")
@@ -83,23 +97,6 @@ def cleanup_physical_files(directory: str, max_age_seconds: int) -> None:
                 os.remove(file_path)
                 logger.info(f"Removed old file: {file_path}")
 
-def cleanup_markers(max_age_seconds: float) -> None:
-    markers_file = os.path.join(os.path.dirname(__file__), "markers.json")
-    if not os.path.exists(markers_file):
-        return
-
-    with open(markers_file, "r") as f:
-        markers = json.load(f)
-
-    current_time = datetime.datetime.now().timestamp()
-    new_markers = [m for m in markers if current_time - m['timestamp'] <= max_age_seconds]
-
-    with open(markers_file, "w") as f:
-        json.dump(new_markers, f, indent=4)
-
-    if new_markers != markers:
-        logger.info(f"Cleaning up {len(markers)-len(new_markers)} markers")
-
 class Handler(FileSystemEventHandler):
     def on_created(self, event):
         if event.is_directory:
@@ -111,7 +108,13 @@ class Handler(FileSystemEventHandler):
         logger.info(f"Added new file to state: {event.src_path}")
 
 def main() -> None:
+    if is_obs_running():
+        logger.info("OBS is already running")
+    else:
+        logger.info("OBS is not running, starting it now")
+        clean_obs_sentinel_files()
         open_obs()
+        
     config = load_config()
     con = open_obs_connection(config["obs"]["host"], config["obs"]["port"], config["obs"]["password"])
 
@@ -129,10 +132,13 @@ def main() -> None:
 
         while running:
             cleanup_physical_files(recording_dir, config["record"]["max_record_time"])
-            cleanup_state_files()
-            cleanup_markers(config["record"]["max_record_time"])
+            cleanup_state(config["record"]["max_record_time"])
             time.sleep(INTERVAL)
     finally:
+        if observer:
+            observer.stop()
+            observer.join()
+
         stop_recording(con)
         con.disconnect()
         logger.info("Daemon stopped")

rewind/paths.py

@@ -6,7 +6,6 @@ from importlib import resources
 
 APP_NAME = "rewind"
 CONFIG_NAME = "config.toml"
-STATE_NAME = "state.json"
 
 def get_config_dir() -> Path:
     base = os.environ.get("XDG_CONFIG_HOME", Path.home() / ".config")
@@ -26,3 +25,8 @@ def load_config() -> dict:
     with config_file.open("rb") as f:
         return tomllib.load(f)
     
+def get_state_dir() -> Path:
+    base = os.path.expanduser("~/.local/share")
+    path = Path(base) / APP_NAME
+    path.mkdir(parents=True, exist_ok=True)
+    return path

rewind/state.py

@@ -4,26 +4,29 @@ import json
 import os
 
 from pathlib import Path
+from rewind.paths import get_state_dir
 
-APP_NAME = "rewind"
 STATE_NAME = "state.json"
-
-def state_dir() -> Path:
-    base = os.path.expanduser("~/.local/share")
-    path = Path(base) / APP_NAME
-    path.mkdir(parents=True, exist_ok=True)
-    return path
+EMPTY_STATE = {
+    "files": [],
+    "markers": []
+}
 
 def get_state_file_path() -> Path:
-    return state_dir() / STATE_NAME
+    return get_state_dir() / STATE_NAME
 
 def load_state() -> dict:
-    if not get_state_file_path().exists():
-        return {"files": []}
-    with get_state_file_path().open() as f:
+    path = get_state_file_path()
+    if not path.exists():
+        return EMPTY_STATE.copy()
+
+    with path.open() as f:
         return json.load(f)
 
 def write_state(state: dict) -> None:
+    if "files" not in state or "markers" not in state:
+        raise ValueError("Invalid state configuration. State must contain 'files' and 'markers' keys.")
+
     tmp = get_state_file_path().with_suffix(".tmp")
     with tmp.open("w") as f:
         json.dump(state, f, indent=2)
@@ -33,6 +36,11 @@ def add_file_to_state(file_path: str) -> None:
     state = load_state()
     files = state.get("files", [])
 
+    # Idempotency guard
+    existing_paths = {f["path"] for f in files}
+    if file_path in existing_paths:
+        return
+
     files.append({
         "path": file_path,
         "timestamp": datetime.datetime.now().timestamp(),
@@ -41,15 +49,59 @@ def add_file_to_state(file_path: str) -> None:
     state["files"] = files
     write_state(state)
 
-def cleanup_state_files() -> None:
+def add_marker_to_state(marker_name: str) -> None:
     state = load_state()
-    files = state.get("files", [])
+    markers = state.get("markers", [])
+
+    existing_markers = {m["name"] for m in markers}
+    if marker_name in existing_markers:
+        raise ValueError("Marker already exists")
+    
+    markers.append({
+        "name": marker_name,
+        "timestamp": datetime.datetime.now().timestamp()
+    })
+
+    state["markers"] = markers
+    write_state(state)
+
+def remove_marker_from_state(marker_name: str) -> None:
+    state = load_state()
+    markers = state.get("markers", [])
+    markers = [marker for marker in markers if marker["name"] != marker_name]
+
+    state["markers"] = markers
+    write_state(state)
+
+def cleanup_state(max_age_seconds: float) -> None:
+    state = load_state()
+    now = datetime.datetime.now().timestamp()
+
+    files = state.get("files", [])
+    markers = state.get("markers", [])
+
+    # First filter by existence
+    files = [
+        f for f in files
+        if os.path.exists(f["path"])
+    ]
+
+    # Then filter by age
+    files = [
+        f for f in files
+        if now - f["timestamp"] <= max_age_seconds
+    ]
+
+    markers = [
+        m for m in markers
+        if now - m["timestamp"] <= max_age_seconds
+    ]
+
+    state["files"] = files
+    state["markers"] = markers
 
-    # Remove old files from state
-    state["files"] = [file for file in files if os.path.exists(file["path"])]
     write_state(state)
 
 def create_state_file_if_needed() -> None:
-    if not os.path.exists(get_state_file_path()):
-        state = {"files": []}
-        write_state(state)
+    if not get_state_file_path().exists():
+        write_state(EMPTY_STATE.copy())