Add OemGatewayFileInterface

Command line arguments allow the choice between a config file and a config obtained through emoncms API. The gateway can now be run without a local emoncms intallation.
albertovm · Jun 14, 2013 · b46cab7 · b46cab7
1 parent 9362982
commit b46cab7
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Showing 3 changed files with 102 additions and 20 deletions.
diff --git a/oemgateway.py b/oemgateway.py
@@ -9,6 +9,7 @@
 
 """
 
+import sys
 import time
 import logging, logging.handlers
 import signal
@@ -41,7 +42,6 @@ def __init__(self, interface):
 
         # Initialize gateway interface and get settings
         self._interface = interface
-        self._interface.check_settings()
         settings = self._interface.settings
 
         # Initialize logging
@@ -173,11 +173,17 @@ def _set_logging_level(self, level):
 if __name__ == "__main__":
 
     # Command line arguments parser
-    parser = argparse.ArgumentParser(description='RFM2Pi Gateway')
+    parser = argparse.ArgumentParser(description='OpenEnergyMonitor Gateway')
+    # Settings source
+    settings_group = parser.add_mutually_exclusive_group()
+    settings_group.add_argument("--config-file", action="store", help='Configuration file')
+    settings_group.add_argument("--config-emoncms", action="store_true", help='Get configuration from emoncms')
+    # Logfile
     parser.add_argument('--logfile', action='store', type=argparse.FileType('a'),
         help='path to optional log file (default: log to Standard error stream STDERR)')
+    # Show settings
     parser.add_argument('--show-settings', action='store_true',
-        help='show RFM2Pi settings and exit (for debugging purposes)')
+        help='show settings and exit (for debugging purposes)')
     args = parser.parse_args()
 
     # Logging configuration
@@ -200,9 +206,16 @@ def _set_logging_level(self, level):
     logger.setLevel(logging.CRITICAL)
 
     # Initialize gateway interface
-    # TODO: cmd line arg to choose another type of interface
-    interface = ogi.OemGatewayEmoncmsInterface()
-
+    if args.config_emoncms:
+        interface = ogi.OemGatewayEmoncmsInterface()
+    elif args.config_file is None:
+        args.config_file = 'oemgateway.conf'
+        try:
+            interface = ogi.OemGatewayFileInterface(args.config_file)
+        except ogi.OemGatewayInterfaceInitError as e:
+            logger.critical(e)
+            sys.exit(0)
+
     # If in "Show settings" mode, print settings and exit
     if args.show_settings:
         interface.check_settings()

diff --git a/oemgatewayinterface.py b/oemgatewayinterface.py
@@ -11,7 +11,7 @@
 import time
 import logging
 import csv
-#import configobj
+from configobj import ConfigObj
 
 """class OemGatewayInterface
 
@@ -88,15 +88,17 @@ def __init__(self):
         # Initialization
         super(OemGatewayEmoncmsInterface, self).__init__()
 
-        # Initialize status update timestamp
+        # Initialize update timestamps
         self._status_update_timestamp = 0
         self._settings_update_timestamp = 0
+        self._retry_time_interval = 60
+
+        # Check settings
+        self.check_settings()
 
     def run(self):
         """Run in background. 
         
-        Return True if settings changed, None otherwise.
-        
         Update raspberry_pi running status.
         
         """
@@ -145,6 +147,7 @@ def check_settings(self):
             import traceback
             self._log.warning("Couldn't get settings, Exception: " + 
                 traceback.format_exc())
+            self._settings_update_timestamp = now + self._retry_time_interval
             return
 
         settings = {}
@@ -206,3 +209,70 @@ def _gateway_running(self):
                 "Couldn't update \"running\" status, Exception: " + 
                 traceback.format_exc())
 
+class OemGatewayFileInterface(OemGatewayInterface):
+
+    def __init__(self, filename):
+
+        # Initialization
+        super(OemGatewayFileInterface, self).__init__()
+
+        # Initialize update timestamp
+        self._settings_update_timestamp = 0
+        self._retry_time_interval = 60
+
+        # Initialize attribute settings as a ConfigObj instance
+        try:
+            self.settings = ConfigObj(filename, file_error=True)
+        except IOError as e:
+            raise OemGatewayInterfaceInitError(e)
+        except SyntaxError as e:
+            raise OemGatewayInterfaceInitError( \
+                'Error parsing config file \"%s\": ' % filename + str(e))
+
+    def check_settings(self):
+        """Check settings
+        
+        Update attribute settings and return True if modified.
+        
+        """
+
+        # Check settings only once per second
+        now = time.time()
+        if (now - self._settings_update_timestamp < 1):
+            return
+        # Update timestamp
+        self._settings_update_timestamp = now
+
+        # Backup settings
+        settings = dict(self.settings)
+
+        # Get settings from file
+        try:
+            self.settings.reload()
+        except IOError as e:
+            self._log.warning('Could not get settings: ' + str(e))
+            self._settings_update_timestamp = now + self._retry_time_interval
+            return
+        except SyntaxError as e:
+            self._log.warning('Could not get settings: ' + 
+                              'Error parsing config file: ' + str(e))
+            self._settings_update_timestamp = now + self._retry_time_interval
+            return
+        except Exception:
+            import traceback
+            self._log.warning("Couldn't get settings, Exception: " + 
+                traceback.format_exc())
+            self._settings_update_timestamp = now + self._retry_time_interval
+            return
+
+        if self.settings != settings:
+            return True
+
+"""class OemGatewayInterfaceInitError
+
+Raise this when init fails.
+
+"""
+class OemGatewayInterfaceInitError(Exception):
+    pass
+
diff --git a/oemgatewaylistener.py b/oemgatewaylistener.py
@@ -12,15 +12,6 @@
 import logging
 import re
 
-
-"""class OemGatewayListenerInitError
-
-Raise this when init fails.
-
-"""
-class OemGatewayListenerInitError(Exception):
-    pass
-
 """class OemGatewayListener
 
 Monitors a data source. 
@@ -198,7 +189,7 @@ def set(self, **kwargs):
                     time.sleep(1)
             elif key == 'sendtimeinterval':
                 if value != self._settings[key]:
-                    self._log.info("Setting time interval to %s", value)
+                    self._log.info("Setting send time interval to %s", value)
                     self._settings[key] = value
 
     def run(self):
@@ -234,3 +225,11 @@ def _send_time(self):
 
         self._ser.write("%02d,00,%02d,00,s" % (now.hour, now.minute))
 
+"""class OemGatewayListenerInitError
+
+Raise this when init fails.
+
+"""
+class OemGatewayListenerInitError(Exception):
+    pass
+