From 108db57271f8d7f958f47751c695004503b4c340 Mon Sep 17 00:00:00 2001 From: marcsello Date: Thu, 14 May 2020 18:26:30 +0200 Subject: [PATCH] Added docstrings to ipw --- ip_watchdog.py | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/ip_watchdog.py b/ip_watchdog.py index 9962f70..b2126a6 100644 --- a/ip_watchdog.py +++ b/ip_watchdog.py @@ -7,12 +7,35 @@ from redis_super_storage import RedisSuperStorage class IPWatchdog: + """ + This is very simple class, that is used to determine if the ip address of the host have changed. + + Internally this class relies on `RedisSuperStorage` to fetch the last used ip address. + + The ip address of the current host is acquired using python's builtin `socket` interface, by requesting an address resolve agains the localhost's host name. + In some scenarios this may result in wrongly identifying the loopback address instead of the assigned address. + In most cases, where the application is run inside a docker container this method will work just fine. + """ + def __init__(self, redis_store: RedisSuperStorage): + """ + During the construction of the object, the host name is of the current machine is cached, for quicker lookups. + + :param redis_store: a RedisSuperStorage instance. + """ self._redis_store = redis_store self._host_name = socket.gethostname() def ip_changed(self) -> Tuple[bool, str]: + """ + This method fetches the last ip address from the RedisSuperStorage instance, and compares it to the current local address. + If the ip address changes the new value is automatically stored in the RedisSuperStorage instance. + + Detection is performed upon calling this method, as well as storing the updated address. + + :return: (changed, ip_address) A tuple with two members, where the first member indicates if the ip address is changed, the second member is the current ip address. + """ old_ip = self._redis_store.current_ip current_ip = socket.gethostbyname(self._host_name)