Added support for context manager.

examples/alarm_email.py

@@ -24,18 +24,13 @@ def main():
 
         # Set up an event handler and open the device
         device.on_alarm += handle_alarm
-        device.open()
-
-        # Wait for events
-        while True:
-            time.sleep(1)
+        with device.open():
+            while True:
+                time.sleep(1)
 
     except Exception, ex:
         print 'Exception:', ex
 
-    finally:
-        device.close()
-
 def handle_alarm(sender, *args, **kwargs):
     """
     Handles alarm events from the AD2.

examples/basics.py

@@ -12,18 +12,13 @@ def main():
 
         # Set up an event handler and open the device
         device.on_message += handle_message
-        device.open()
-
-        # Wait for events.
-        while True:
-            time.sleep(1)
+        with device.open():
+            while True:
+                time.sleep(1)
 
     except Exception, ex:
         print 'Exception:', ex
 
-    finally:
-        device.close()
-
 def handle_message(sender, *args, **kwargs):
     """
     Handles message events from the AD2.

examples/rf_device.py

@@ -22,18 +22,13 @@ def main():
 
         # Set up an event handler and open the device
         device.on_rfx_message += handle_rfx
-        device.open()
-
-        # Wait for events.
-        while True:
-            time.sleep(1)
+        with device.open():
+            while True:
+                time.sleep(1)
 
     except Exception, ex:
         print 'Exception:', ex
 
-    finally:
-        device.close()
-
 def handle_rfx(sender, *args, **kwargs):
     """
     Handles RF message events from the AD2.

examples/serialport.py

@@ -16,20 +16,16 @@ def main():
 
         # Set up an event handler and open the device
         device.on_message += handle_message
-        device.open(baudrate=BAUDRATE)          # Override the default SerialDevice
-                                                # baudrate since we're using a USB
-                                                # device over serial in this example.
 
-        # Wait for events.
-        while True:
-            time.sleep(1)
+        # Override the default SerialDevice baudrate since we're using a USB device
+        # over serial in this example.
+        with device.open(baudrate=BAUDRATE):
+            while True:
+                time.sleep(1)
 
     except Exception, ex:
         print 'Exception:', ex
 
-    finally:
-        device.close()
-
 def handle_message(sender, *args, **kwargs):
     """
     Handles message events from the AD2.

examples/socket_example.py

@@ -17,18 +17,13 @@ def main():
 
         # Set up an event handler and open the device
         device.on_message += handle_message
-        device.open()
-
-        # Wait for events.
-        while True:
-            time.sleep(1)
+        with device.open():
+            while True:
+                time.sleep(1)
 
     except Exception, ex:
         print 'Exception:', ex
 
-    finally:
-        device.close()
-
 def handle_message(sender, *args, **kwargs):
     """
     Handles message events from the AD2.

examples/ssl_socket.py

@@ -31,18 +31,13 @@ def main():
 
         # Set up an event handler and open the device
         device.on_message += handle_message
-        device.open()
-
-        # Wait for events.
-        while True:
-            time.sleep(1)
+        with device.open():
+            while True:
+                time.sleep(1)
 
     except Exception, ex:
         print 'Exception:', ex
 
-    finally:
-        device.close()
-
 def handle_message(sender, *args, **kwargs):
     """
     Handles message events from the AD2.

examples/virtual_zone_expander.py

@@ -34,24 +34,19 @@ def main():
         device.on_zone_fault += handle_zone_fault
         device.on_zone_restore += handle_zone_restore
 
-        device.open()
+        with device.open():
+            last_update = time.time()
+            while True:
+                if time.time() - last_update > WAIT_TIME:
+                    last_update = time.time()
 
-        # Wait for events.
-        last_update = time.time()
-        while True:
-            if time.time() - last_update > WAIT_TIME:
-                last_update = time.time()
+                    device.fault_zone(TARGET_ZONE)
 
-                device.fault_zone(TARGET_ZONE)
-
-            time.sleep(1)
+                time.sleep(1)
 
     except Exception, ex:
         print 'Exception:', ex
 
-    finally:
-        device.close()
-
 def handle_zone_fault(sender, *args, **kwargs):
     """
     Handles zone fault messages.

pyad2/ad2.py

@@ -85,6 +85,20 @@ class AD2(object):
         self.emulate_lrr = False
         self.deduplicate = False
 
+    def __enter__(self):
+        """
+        Support for context manager __enter__.
+        """
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """
+        Support for context manager __exit__.
+        """
+        self.close()
+
+        return False
+
     @property
     def id(self):
         """
@@ -107,6 +121,8 @@ class AD2(object):
         self._device.open(baudrate=baudrate, no_reader_thread=no_reader_thread)
         self.get_config()
 
+        return self
+
     def close(self):
         """
         Closes the device.

pyad2/devices.py

@@ -37,6 +37,20 @@ class Device(object):
         self._running = False
         self._read_thread = Device.ReadThread(self)
 
+    def __enter__(self):
+        """
+        Support for context manager __enter__.
+        """
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """
+        Support for context manager __exit__.
+        """
+        self.close()
+
+        return False
+
     @property
     def id(self):
         """
@@ -338,10 +352,12 @@ class USBDevice(Device):
 
         else:
             self._running = True
+            self.on_open()
+
             if not no_reader_thread:
                 self._read_thread.start()
 
-            self.on_open()
+        return self
 
     def close(self):
         """
@@ -630,6 +646,8 @@ class SerialDevice(Device):
             if not no_reader_thread:
                 self._read_thread.start()
 
+        return self
+
     def close(self):
         """
         Closes the device.
@@ -890,12 +908,13 @@ class SocketDevice(Device):
 
         else:
             self._running = True
-
             self.on_open()
 
             if not no_reader_thread:
                 self._read_thread.start()
 
+        return self
+
     def close(self):
         """
         Closes the device.