#!/usr/bin/env python3 """Claude Usage Tracker Daemon — Windows (Phase 2). Reads the Claude OAuth token from the native-Windows credentials path and polls the Anthropic API for rate-limit utilization data. BLE glue added in later plans. """ import asyncio import datetime import json import logging import logging.handlers import os import re import signal import sys import threading import time from pathlib import Path import httpx from bleak import BleakClient, BleakScanner from bleak.exc import BleakError DEVICE_NAME = "Claude Controller" SERVICE_UUID = "4c41555a-4465-7669-6365-000000000001" RX_CHAR_UUID = "4c41555a-4465-7669-6365-000000000002" REQ_CHAR_UUID = "4c41555a-4465-7669-6365-000000000004" POLL_INTERVAL = 60 TICK = 5 SCAN_TIMEOUT = 8.0 CONNECT_RETRIES = 3 # D-01: attempts before giving up on a device CONNECT_RETRY_DELAY = 2.0 # D-01: seconds between failed connect attempts ZOMBIE_BREAK_LIMIT = 1 # D-03: consecutive write failures before abandoning a half-open link # N=1: breaks at T=60s, leaves ~60s headroom for reconnect+poll inside 120s SLA # N=2 would bust the 120s budget before reconnect even begins RECONNECT_BACKOFF_CAP = 8 # D-05: fast-reconnect cap (seconds); keeps stacked retries inside 120s SLA # ~5–10s band per CONTEXT.md Claude's Discretion; 8 chosen as middle ground API_URL = "https://api.anthropic.com/v1/messages" API_HEADERS_TEMPLATE = { "anthropic-version": "2023-06-01", "anthropic-beta": "oauth-2025-04-20", "Content-Type": "application/json", "User-Agent": "claude-code/2.1.5", } API_BODY = { "model": "claude-haiku-4-5-20251001", "max_tokens": 1, "messages": [{"role": "user", "content": "hi"}], } def _build_file_logger() -> logging.Logger | None: """Create a rotating file logger for field diagnostics, or None. Autostart launches the tray under pythonw.exe, which has no console — stdout is discarded (and is in fact None, making print() unsafe). A rotating file is then the ONLY trail when the daemon stalls in the field. Windows-only: on the Linux dev box / CI the console print() suffices, and gating to win32 keeps the pure-helper unit tests from writing stray log files. """ if sys.platform != "win32": return None logger = logging.getLogger("clawdmeter.daemon") if logger.handlers: return logger # idempotent across re-import (tray imports this module) base = Path(os.environ.get("LOCALAPPDATA", Path.home() / "AppData" / "Local")) path = base / "Clawdmeter" / "daemon.log" try: path.parent.mkdir(parents=True, exist_ok=True) handler = logging.handlers.RotatingFileHandler( path, maxBytes=512 * 1024, backupCount=3, encoding="utf-8" ) except OSError: return None # best-effort — logging setup must never stop the daemon handler.setFormatter(logging.Formatter("%(asctime)s %(message)s", "%Y-%m-%d %H:%M:%S")) logger.addHandler(handler) logger.setLevel(logging.INFO) logger.propagate = False return logger _FILE_LOGGER = _build_file_logger() def log(msg: str) -> None: line = f"[{time.strftime('%H:%M:%S')}] {msg}" # Under pythonw sys.stdout is None and print() would raise — guard it so a # missing console can never crash the daemon thread (the silent-freeze mode). try: print(line, flush=True) except (OSError, ValueError, AttributeError, RuntimeError): pass if _FILE_LOGGER is not None: _FILE_LOGGER.info(msg) class AuthError(Exception): """Raised by poll_api on a genuine 401/403 — the token really is expired or invalid and the user must re-run `claude login`. Distinct from a None return, which means a TRANSIENT failure (network/DNS, timeout, rate-limit, 5xx) that must NOT be mislabeled as a token problem (SC#5: a boot-time `getaddrinfo failed` DNS blip wrongly fired the 'token expired' toast).""" async def poll_api(token: str) -> dict | None: headers = dict(API_HEADERS_TEMPLATE) headers["Authorization"] = f"Bearer {token}" try: async with httpx.AsyncClient(timeout=20.0) as http: resp = await http.post(API_URL, headers=headers, json=API_BODY) except httpx.HTTPError as e: # Network/DNS/timeout — transient. Return None (no toast), retry next tick. log(f"API call failed: {e}") return None if resp.status_code in (401, 403): # Genuine auth rejection — the ONLY case that warrants the actionable # "run claude login" toast. log(f"API HTTP {resp.status_code}: {resp.text[:200]}") raise AuthError(resp.status_code) if resp.status_code >= 400: # Other 4xx/5xx (rate-limit, server error) — transient, not a token issue. log(f"API HTTP {resp.status_code}: {resp.text[:200]}") return None def hdr(name: str, default: str = "0") -> str: return resp.headers.get(name, default) now = time.time() def reset_minutes(reset_ts: str) -> int: try: r = float(reset_ts) except ValueError: return 0 mins = (r - now) / 60.0 return int(round(mins)) if mins > 0 else 0 def pct(util: str) -> int: try: return int(round(float(util) * 100)) except ValueError: return 0 payload = { "s": pct(hdr("anthropic-ratelimit-unified-5h-utilization")), "sr": reset_minutes(hdr("anthropic-ratelimit-unified-5h-reset")), "w": pct(hdr("anthropic-ratelimit-unified-7d-utilization")), "wr": reset_minutes(hdr("anthropic-ratelimit-unified-7d-reset")), "st": hdr("anthropic-ratelimit-unified-5h-status", "unknown"), "ok": True, } return payload async def scan_for_device(): """Scan for DEVICE_NAME and return the BLEDevice, or None.""" log(f"Scanning for '{DEVICE_NAME}' ({SCAN_TIMEOUT}s)...") device = await BleakScanner.find_device_by_name(DEVICE_NAME, timeout=SCAN_TIMEOUT) if device: log(f"Found: {device.address}") return device # BLEDevice or None — NOT an address string class Session: def __init__(self, client: BleakClient) -> None: self.client = client self.refresh_requested = asyncio.Event() def _on_refresh(self, _char, _data: bytearray) -> None: log("Refresh requested by device") self.refresh_requested.set() async def setup_refresh_subscription(self) -> None: # The refresh subscription is optional — the 60s poll loop works without it. # WinRT's start_notify() CCCD write can raise a raw OSError/WinError (not # wrapped as BleakError) when the peer GATT server is transiently unavailable, # e.g. a just-power-cycled ESP32 whose server is not yet ready (G-03-01, SC#3). # Degrade gracefully instead of crashing the daemon so it stays single-process # across a power-cycle reconnect (SC#4, no restart). try: await self.client.start_notify(REQ_CHAR_UUID, self._on_refresh) except (BleakError, ValueError, OSError) as e: log(f"Refresh subscription unavailable: {e}") async def write_payload(self, payload: dict) -> bool: data = json.dumps(payload, separators=(",", ":")).encode() log(f"Sending: {data.decode()}") try: await self.client.write_gatt_char(RX_CHAR_UUID, data, response=False) return True except (BleakError, OSError) as e: # WinRT can raise a raw OSError/WinError (NOT wrapped as BleakError) # when the peer GATT server goes transiently unavailable mid-write — # the same failure class setup_refresh_subscription() guards against. # Returning False trips the zombie-link break -> clean reconnect, # rather than an uncaught exception killing the daemon thread (the # silent-freeze failure mode, SC#2 field report). log(f"Write failed: {e}") return False def _extract_access_token(blob: str) -> str | None: """Pull the accessToken out of a credentials blob. Claude Code stores credentials as a JSON object; the blob may also be nested ({"claudeAiOauth": {"accessToken": "..."}}). Fall back to a regex match so unexpected shapes still work, and finally treat the blob as a raw token if nothing else matches. """ blob = blob.strip() if not blob: return None try: data = json.loads(blob) except json.JSONDecodeError: data = None if isinstance(data, dict): # direct: {"accessToken": "..."} tok = data.get("accessToken") if isinstance(tok, str) and tok.strip(): return tok # nested: {"claudeAiOauth": {"accessToken": "..."}} for v in data.values(): if isinstance(v, dict): tok = v.get("accessToken") if isinstance(tok, str) and tok.strip(): return tok m = re.search(r'"accessToken"\s*:\s*"([^"]+)"', blob) if m: return m.group(1) # Raw token (no JSON wrapper) — must look plausible (sk-ant-... etc.) if re.fullmatch(r"[A-Za-z0-9_\-.~+/=]{20,}", blob): return blob return None def _windows_credential_candidates() -> list[Path]: """Return the ordered list of credential file paths to probe (first hit wins). Priority: 1. CLAUDE_CREDENTIALS_PATH env override (D-03, project-specific) 2. CLAUDE_CONFIG_DIR env override (official Claude override) 3. D-02 candidate list: home/.claude, LOCALAPPDATA/Claude, APPDATA/Claude """ # Priority 1: project-specific env override (D-03) if override := os.environ.get("CLAUDE_CREDENTIALS_PATH"): return [Path(override)] # Priority 2: official CLAUDE_CONFIG_DIR env override if config_dir := os.environ.get("CLAUDE_CONFIG_DIR"): return [Path(config_dir) / ".credentials.json"] # Priority 3: D-02 candidate list — first hit wins home = Path.home() local_appdata = Path(os.environ.get("LOCALAPPDATA", home / "AppData" / "Local")) appdata = Path(os.environ.get("APPDATA", home / "AppData" / "Roaming")) return [ home / ".claude" / ".credentials.json", # primary (confirmed by docs) local_appdata / "Claude" / ".credentials.json", # fallback 2 appdata / "Claude" / ".credentials.json", # fallback 3 ] def read_token() -> str | None: """Read the Claude OAuth access token from the first available credential file.""" for path in _windows_credential_candidates(): try: return _extract_access_token(path.read_text(encoding="utf-8")) except OSError: continue return None def _read_expiry() -> str: """Return human-readable expiry from the first-hit credentials file. Reads claudeAiOauth.expiresAt (epoch milliseconds — JS convention). Divides by 1000 before passing to fromtimestamp (Python expects seconds). Returns 'expiry unknown' on any parse failure. """ for path in _windows_credential_candidates(): try: raw = path.read_text(encoding="utf-8") except OSError: continue try: data = json.loads(raw) oauth = data.get("claudeAiOauth", {}) expires_ms = oauth.get("expiresAt") if expires_ms is None: return "expiry unknown" # CRITICAL: expiresAt is JS-convention epoch milliseconds; divide by 1000 # before fromtimestamp (Python expects seconds). Raw value -> year ~57000. dt = datetime.datetime.fromtimestamp( expires_ms / 1000, tz=datetime.timezone.utc ) return dt.strftime("%Y-%m-%d %H:%M UTC") except (TypeError, ValueError, OSError, AttributeError, json.JSONDecodeError): return "expiry unknown" return "expiry unknown" async def _wait_first(*events: asyncio.Event, timeout: float) -> None: """Return when any of `events` is set, or after `timeout` seconds. Lets the poll loop's TICK wait wake immediately on a stop signal (clean, responsive Quit) without losing the refresh-request wakeup — instead of waiting only on refresh_requested and re-checking stop_event up to TICK later. Cancels and drains the loser tasks so they don't warn. """ tasks = [asyncio.ensure_future(e.wait()) for e in events] try: await asyncio.wait(tasks, timeout=timeout, return_when=asyncio.FIRST_COMPLETED) finally: for t in tasks: t.cancel() await asyncio.gather(*tasks, return_exceptions=True) async def connect_and_run(device, stop_event: asyncio.Event, tray_state=None) -> bool: """Connect to device and poll until disconnected or stopped. Returns True if at least one successful write occurred. """ log(f"Connecting to {device.address}...") # D-01: retry wrapper — defeats WinRT post-wake failure modes # (Could not get GATT services: Unreachable, stale is_connected). # Rebuild a fresh BleakClient each attempt (locked D-05 recipe). client = None for attempt in range(CONNECT_RETRIES): # D-05: pass BLEDevice (not address string), address_type="random" (NimBLE # static-random), use_cached_services=False (DIY firmware — WinRT GATT cache # may be stale after firmware reflash). client = BleakClient( device, address_type="random", use_cached_services=False, ) try: await client.connect() except (BleakError, asyncio.TimeoutError) as e: log(f"Connection attempt {attempt + 1}/{CONNECT_RETRIES} failed: {e}") try: await client.disconnect() except BleakError: pass if attempt < CONNECT_RETRIES - 1: await asyncio.sleep(CONNECT_RETRY_DELAY) continue if not client.is_connected: log(f"Connection attempt {attempt + 1}/{CONNECT_RETRIES} failed (not connected)") try: await client.disconnect() except BleakError: pass if attempt < CONNECT_RETRIES - 1: await asyncio.sleep(CONNECT_RETRY_DELAY) continue # Connected successfully break else: log(f"Connection failed after {CONNECT_RETRIES} attempts") return False log("Connected") session = Session(client) await session.setup_refresh_subscription() last_poll = 0.0 # D-03: poll immediately on first connect used_successfully = False consecutive_failures = 0 # D-03: zombie-link break counter try: while client.is_connected and not stop_event.is_set(): now = time.time() elapsed = now - last_poll if session.refresh_requested.is_set() or elapsed >= POLL_INTERVAL: session.refresh_requested.clear() token = read_token() # D-09: fresh each cycle if not token: log("No token; skipping poll") if tray_state: tray_state.set_error("token expired — run claude login") else: try: payload = await poll_api(token) except AuthError: # Real 401/403 — token genuinely needs a refresh. if tray_state: tray_state.set_error("token expired — run claude login") payload = None if payload is not None: if await session.write_payload(payload): last_poll = time.time() used_successfully = True consecutive_failures = 0 # D-03: reset on success if tray_state: tray_state.set_connected(time.time()) else: consecutive_failures += 1 if consecutive_failures >= ZOMBIE_BREAK_LIMIT: log( f"Zombie link detected ({consecutive_failures} consecutive" f" write failures); abandoning connection" ) break # else: payload is None from a TRANSIENT failure (network/DNS, # timeout, rate-limit, 5xx). poll_api already logged it; do NOT # toast "token expired" — that mislabeled a boot-time DNS blip # as an auth problem (SC#5). Leave tray state unchanged; the next # tick retries and set_connected() recovers it. # Wake on a refresh request OR a stop, whichever comes first. Waking # promptly on stop_event is what lets the finally below run # client.disconnect() before the process exits, so the peer gets a # clean GATT disconnect (returns to its waiting screen) instead of # being left frozen on stale data after Quit (SC#3 graceful shutdown). await _wait_first(session.refresh_requested, stop_event, timeout=TICK) finally: # Clean GATT disconnect on the way out — this is what tells the peripheral # the link is gone. WinRT can surface a raw OSError (not BleakError) here, # so swallow both; the link tears down regardless once we exit. try: await client.disconnect() except (BleakError, OSError): pass log("Device disconnected" if not stop_event.is_set() else "Stopping") return used_successfully def _next_backoff(current: int, cap: int) -> int: """D-05: double current backoff value, clamped to cap. Pure helper — unit-testable without driving the main loop. Used by both slow-search (cap=60) and fast-reconnect (cap=RECONNECT_BACKOFF_CAP) regimes. """ return min(current * 2, cap) async def main(tray_state=None) -> None: stop_event = asyncio.Event() loop = asyncio.get_running_loop() # Populate the shared state object so the tray can route Quit through # loop.call_soon_threadsafe (RESEARCH Pitfall 2). Additive — the existing # stop_event = asyncio.Event() line above is unchanged. if tray_state is not None: tray_state.loop = loop tray_state.stop_event = stop_event def _stop(*_args: object) -> None: log("Daemon stopping") stop_event.set() # OS signal handlers can only be installed from the main thread, and # loop.add_signal_handler is unsupported on Windows. When running under the # tray (04-03) the loop lives in a background thread and the tray owns clean # shutdown via stop_event (loop.call_soon_threadsafe), so skip silently there. if threading.current_thread() is threading.main_thread(): for sig in (signal.SIGINT, signal.SIGTERM): try: loop.add_signal_handler(sig, _stop) except NotImplementedError: # Windows: add_signal_handler not supported; fall back to signal.signal try: signal.signal(sig, _stop) except ValueError: # Not the main thread of the main interpreter — tray owns shutdown. pass log("=== Claude Usage Tracker Daemon (BLE, Windows) ===") log(f"Poll interval: {POLL_INTERVAL}s") # D-05: two distinct backoff regimes — slow-search (device absent) vs fast-reconnect (link dropped) search_backoff = 1 # caps at 60s — gentle, for a device that is genuinely absent/off reconnect_backoff = 1 # caps at RECONNECT_BACKOFF_CAP — fast, to clear the 120s SLA after a drop while not stop_event.is_set(): device = await scan_for_device() if not device: # Slow-search regime: device was not found by scan — back off gently if tray_state: tray_state.set_scanning() log(f"Device not found, retrying in {search_backoff}s...") try: await asyncio.wait_for(stop_event.wait(), timeout=search_backoff) except asyncio.TimeoutError: pass search_backoff = _next_backoff(search_backoff, 60) continue ok = await connect_and_run(device, stop_event, tray_state) if not ok: # Fast-reconnect regime: had/attempted a link that dropped — retry quickly if tray_state: tray_state.set_scanning() log(f"Connection lost, reconnecting in {reconnect_backoff}s...") try: await asyncio.wait_for(stop_event.wait(), timeout=reconnect_backoff) except asyncio.TimeoutError: pass reconnect_backoff = _next_backoff(reconnect_backoff, RECONNECT_BACKOFF_CAP) else: # Successful session — reset reconnect counter to floor; search_backoff also reset reconnect_backoff = 1 search_backoff = 1 if __name__ == "__main__": if sys.platform != "win32": print( "Warning: running under Linux/WSL — WinRT BLE will not be available.", file=sys.stderr, ) try: asyncio.run(main()) except KeyboardInterrupt: sys.exit(0)