complete SpaceAPI integration

[saartuer.git] / spaceapi.py

diff --git a/spaceapi.py b/spaceapi.py
new file mode 100644 (file)
index 0000000..89e3678
--- /dev/null
+++ b/spaceapi.py
@@ -0,0 +1,57 @@
+from threading import Lock
+from libtuer import ThreadFunction, logger
+import urllib.request
+
+from config import spaceApiKey
+
+class SpaceApi:
+       def __init__ (self, waker):
+               self._state_to_set = None
+               self._state_last_set = None
+               self._running = True
+               self.set_state = ThreadFunction(self._set_state, "Space API")
+               self._set_state_lock = Lock()
+               waker.register(self.set_state, 10.0) # re-try setting the state every 10 seconds
+       
+       def stop (self):
+               self.set_state.stop()
+       
+       def _do_request(self, state):
+               state_val = 1 if state else 0
+               try:
+                       logger.info("Setting SpaceAPI to %d" % state_val)
+                       url = "http://spaceapi.hacksaar.de/status.php?action=update&key=%s&status=%d" % (spaceApiKey, state_val)
+                       response = urllib.request.urlopen(url, timeout=5.0)
+                       responseText = response.read().decode('utf-8').strip()
+                       if response.getcode() == 200 and responseText == "UpdateSuccessful": return True
+                       logger.error("SpaceAPI returned unexpected code %d, content %s" % (response.getcode(), responseText))
+                       return False
+               except urllib.request.URLError as e:
+                       logger.error("SpaceAPI update returned error: %s" % str(e))
+                       return False
+       
+       # set_state is the asynchronous version of _set_state (see __init__)
+       def _set_state (self, state = None):
+               '''Sets the state, if None: leave state unchanged and re-try if previous attempts failed'''
+               if state is not None:
+                       self._state_to_set = state
+               else:
+                       # always have a local variable because of parallelism
+                       state = self._state_to_set
+               
+               if not self._set_state_lock.acquire(False):
+                       # we don't want many threads to wait here
+                       # the next status update will fix everything anyways
+                       pass
+               else:
+                       # got the lock
+                       try:
+                               # check if there's something we need to do
+                               if self._state_last_set == state: return
+                               # take action!
+                               success = self._do_request(state)
+                               # TODO error too often -> log critical to send mails
+                               if success:
+                                       self._state_last_set = state
+                       finally:
+                               self._set_state_lock.release()