Fixes #26: Deal slightly better with caching; this will need a big re…

…factor to do properly.

ouimeaux/cli.py

@@ -141,6 +141,9 @@ def server(args):
 
 
 def wemo():
+    import ouimeaux.utils
+    ouimeaux.utils._RETRIES = 0
+
     parser = argparse.ArgumentParser()
 
     parser.add_argument("-b", "--bind", default=None,

ouimeaux/config.py

@@ -80,11 +80,21 @@ def __init__(self, shelf):
     def empty(self):
         return not self._shelf.get('devices')
 
+    def clear(self):
+        self._shelf.clear()
+
     def add_device(self, device):
         assert isinstance(device, Device)
         d = self._shelf.setdefault('devices', {})
         d[device.name] = device
 
+    def invalidate(self, device):
+        assert isinstance(device, Device)
+        d = self._shelf.setdefault('devices', {})
+        d.pop(device.name)
+        self._shelf.clear()
+        self._shelf['devices'] = d
+
     @property
     def devices(self):
         try:

ouimeaux/device/__init__.py

@@ -9,6 +9,7 @@
 log = logging.getLogger(__name__)
 
 
+class DeviceUnreachable(Exception): pass
 class UnknownService(Exception): pass
 
 
@@ -55,6 +56,12 @@ def get_service(self, name):
     def list_services(self):
         return self.services.keys()
 
+    def ping(self):
+        try:
+            self.get_state()
+        except Exception:
+            raise DeviceUnreachable(self)
+
     def explain(self):
         for name, svc in self.services.iteritems():
             print name

ouimeaux/environment.py

@@ -1,8 +1,10 @@
 import logging
 
 import gevent
+import requests
 
 from ouimeaux.config import get_cache, WemoConfiguration
+from ouimeaux.device import DeviceUnreachable
 from ouimeaux.device.switch import Switch
 from ouimeaux.device.insight import Insight
 from ouimeaux.device.lightswitch import LightSwitch
@@ -151,9 +153,14 @@ def _process_device(self, device, cache=None):
             self.registry.register(device)
             self.registry.on(device, 'BinaryState',
                              device._update_state)
-        if cache if cache is not None else self._with_cache:
-            with get_cache() as c:
-                c.add_device(device)
+        with get_cache() as c:
+            try:
+                device.ping()
+            except DeviceUnreachable:
+                return
+            else:
+                if cache if cache is not None else self._with_cache:
+                    c.add_device(device)
         devicefound.send(device)
         callback(device)
 

ouimeaux/utils.py

@@ -56,28 +56,35 @@ def matches(s):
     return matches
 
 
-def retry_with_delay(f, retries=10, delay=60):
+# This is pretty arbitrary. I'm choosing, for no real reason, the length of
+# a subscription.
+_RETRIES = 1801/60
+
+
+def get_retries():
+    return _RETRIES
+
+
+def retry_with_delay(f, delay=60):
     """
     Retry the wrapped requests.request function in case of ConnectionError.
     Optionally limit the number of retries or set the delay between retries.
     """
     @wraps(f)
     def inner(*args, **kwargs):
-        remaining = retries
+        kwargs['timeout'] = 1
+        remaining = get_retries() + 1
         while remaining:
+            remaining -= 1
             try:
                 return f(*args, **kwargs)
             except requests.ConnectionError:
                 if not remaining:
                     raise
-                remaining -= 1
                 gevent.sleep(delay)
     return inner
 
 
-# This is pretty arbitrary. I'm choosing, for no real reason, the length of
-# a subscription.
-_RETRIES = 1801/60
-requests_get = retry_with_delay(requests.get, retries=_RETRIES)
-requests_post = retry_with_delay(requests.post, retries=_RETRIES)
-requests_request = retry_with_delay(requests.request, retries=_RETRIES)
+requests_get = retry_with_delay(requests.get)
+requests_post = retry_with_delay(requests.post)
+requests_request = retry_with_delay(requests.request)