Our app provide multi devices sync feature.
A same Google account, with multiple devices, will have multiple Firebase token Id
FirebaseInstanceId.getInstance().getInstanceId()
Over the time, a Firebase token Id from a same device might become invalid/ expired, and being refreshed with a new Firebase token Id.
In our backend, this is how we check our stored Firebase token Id, to determine whether they are still valid.
def is_valid_token(token):
try:
failure_counter = 0
while True:
if failure_counter >= 3:
return False
body = '{"dry_run": true, "registration_ids":["' + token + '"]}'
req = urllib.request.Request('https://fcm.googleapis.com/fcm/send')
req.add_header('Content-Type', 'application/json')
req.add_header('Authorization', 'key=' + constants.FCM_AUTHORIZATION_KEY)
with urllib.request.urlopen(req, body.encode('utf8')) as response:
string = response.read().decode('utf8')
d = json.loads(string)
if d['failure'] == 1:
failure_counter = failure_counter + 1
continue
else:
return True
except Exception as e:
logging.error(e, exc_info=True)
exc_type, exc_obj, exc_tb = sys.exc_info()
error = exc_type
message = str(e)
line_number = exc_tb.tb_lineno
filename = os.path.split(exc_tb.tb_frame.f_code.co_filename)[1]
insert_into_error_log(error, message, filename, line_number, token)
return True
What we did is, we perform a dry_run mode FCM send. If such operation fails for 3 times continuously, we will mark the token as invalid.
However, we notice that such approach isn't accurate enough. As, we have user who only owns 2 devices. However, there are 12 different valid Firebase token id associate with his single Google account.
I was wondering, do you have any reliable approach, to validate a Firebase token id, besides performing dry_run FCM send?
