record.py: if disconnected, attempt to reconnect forever

muselsl/backends.py

@@ -1,11 +1,14 @@
 import asyncio
 import atexit
+import sys
 import time
 try:
     import bleak
 except ModuleNotFoundError as error:
     bleak = error
 
+RETRY_SLEEP = 1
+
 def _wait(coroutine):
     loop = asyncio.get_event_loop()
     return loop.run_until_complete(coroutine)
@@ -32,18 +35,38 @@ def scan(self, timeout=10):
             raise bleak
         devices = _wait(bleak.BleakScanner.discover(timeout))
         return [{'name':device.name, 'address':device.address} for device in devices]
-    def connect(self, address):
+    def connect(self, address, retries):
         result = BleakDevice(self, address)
-        result.connect()
+        if not result.connect(retries):
+            return None
         return result
 
 class BleakDevice:
     def __init__(self, adapter, address):
         self._adapter = adapter
-        self._client = bleak.BleakClient(address)
-    def connect(self):
-        _wait(self._client.connect())
+        self._address = address
+        self._client = None
+    # Use retries=-1 to continue attempting to reconnect forever
+    def connect(self, retries):
+        attempts = 1
+        while True:
+            self._client = bleak.BleakClient(self._address)
+            if attempts > 1:
+                print(f'Connection attempt {attempts}')
+            try:
+                _wait(self._client.connect())
+            except (
+                bleak.exc.BleakDeviceNotFoundError, bleak.exc.BleakError
+            ) as err:
+                print(f'Failed to connect: {err}', file=sys.stderr)
+                if attempts == 1 + retries:
+                    return False
+                sleep(RETRY_SLEEP)
+                attempts += 1
+            else:
+                break
         self._adapter.connected.add(self)
+        return True
     def disconnect(self):
         _wait(self._client.disconnect())
         self._adapter.connected.remove(self)

muselsl/muse.py

@@ -60,7 +60,7 @@ def __init__(self,
         self.preset = preset
         self.disable_light = disable_light
 
-    def connect(self, interface=None):
+    def connect(self, interface=None, retries=0):
         """Connect to the device"""
         try:
             if self.backend == 'bluemuse':
@@ -81,7 +81,11 @@ def connect(self, interface=None):
                         serial_port=self.interface)
 
                 self.adapter.start()
-                self.device = self.adapter.connect(self.address)
+                if ((device := self.adapter.connect(self.address, retries))
+                    is None):
+                    return False
+                self.device = device
+
                 if(self.preset != None):
                     self.select_preset(self.preset)
 

muselsl/record.py

@@ -1,6 +1,8 @@
+import bleak
 import numpy as np
 import pandas as pd
 import os
+import sys
 from typing import Union, List, Optional
 from pathlib import Path
 from pylsl import StreamInlet, resolve_byprop
@@ -13,7 +15,6 @@
 
 # Records a fixed duration of EEG data from an LSL stream into a CSV file
 
-
 def record(
     duration: int,
     filename=None,
@@ -212,7 +213,9 @@ def save_eeg(new_samples, new_timestamps):
         timestamps.append(new_timestamps)
 
     muse = Muse(address, save_eeg, backend=backend)
-    muse.connect()
+    if not muse.connect():
+        print(f'Failed to connect to Muse: {address}', file=sys.stderr)
+        return
     muse.start()
 
     t_init = time()
@@ -221,13 +224,32 @@ def save_eeg(new_samples, new_timestamps):
     last_update = t_init
     while (time() - t_init) < duration:
         try:
-            backends.sleep(1)
-
-            # Send a keep alive every minute
-            if time() - last_update > 60:
-                last_update = time()
-                muse.keep_alive()
+            try:
+                backends.sleep(1)
+
+                # Send a keep alive every 10 secs
+                if time() - last_update > 10:
+                    last_update = time()
+                    muse.keep_alive()
+            except bleak.exc.BleakError:
+                print('Disconnected. Attempting to reconnect...')
+                # Do not giveup since we make a best effort to continue
+                # data collection. Assume device is out of range or another
+                # temp error.
+                while True:
+                    muse.connect(retries=-1)
+                    try:
+                        muse.resume()
+                    except bleak.exc.BleakDBusError:
+                        # Something is wrong with this connection
+                        print('DBus error occurred. Reconnecting.')
+                        muse.disconnect()
+                        continue
+                    else:
+                        break
+                print('Connected. Continuing with data collection...')
         except KeyboardInterrupt:
+            print('Interrupt received. Exiting data collection.')
             break
 
     muse.stop()