refactor

2 files changed, 66 insertions, 31 deletions

diff --git a/config/config.yaml b/config/config.yaml
index 332f6b9..6dc26a4 100644
--- a/config/config.yaml
+++ b/config/config.yaml
@@ -1,5 +1,8 @@
-log_file_path: /var/log/weather_logger/receiver.log
-pid_file_path: /run/weather_logger/receiver.log
+device_path:   "/dev/ttyUSB0"
+database_path: "/usr/local/share/weather_logger/weather.db"
+log_file_path: "/var/log/weather_logger/receiver.log"
+pid_file_path: "/run/weather_logger/pid"
+
 
 locations:
   Berlin:
@@ -17,4 +20,4 @@ locations:
       handle: "outside"
       type: "THGR810, THGN800"
 
-active-location: Berlin
+active_location: Berlin
diff --git a/weather-logger-receiver b/weather-logger-receiver
index 389a9de..fd0c8e4 100755
--- a/weather-logger-receiver
+++ b/weather-logger-receiver
@@ -11,8 +11,8 @@ import yaml
 from RFXtrx import PySerialTransport
 
 
-def setup_database(path="weather.db"):
-    db_connection = sqlite3.connect(path)
+def setup_database(database_path, logger):
+    db_connection = sqlite3.connect(database_path)
     db_cursor = db_connection.cursor()
     try:
         db_cursor.execute("CREATE TABLE weather( \
@@ -22,26 +22,19 @@ def setup_database(path="weather.db"):
                                           temperature FLOAT, \
                                           humidity FLOAT);")
     except sqlite3.OperationalError:
+        logger.info("Not re-creating 'weather' table")
         pass
 
     return db_connection
 
 
-def setup_serial(device="/dev/ttyUSB0"):
-    serial_connection = PySerialTransport(device)
+def setup_serial(device_path):
+    serial_connection = PySerialTransport(device_path)
     serial_connection.reset()
 
     return serial_connection
 
 
-def load_known_devices(location, path="known-devices.yaml"):
-    known_devices = None
-    with open(path, "r") as f:
-        known_devices = yaml.safe_load(f.read())
-
-    return known_devices[location]
-
-
 def add_data_to_db(data, handle, db_connection):
     db_cursor = db_connection.cursor()
     db_cursor.execute(f"INSERT INTO weather \
@@ -53,24 +46,25 @@ def add_data_to_db(data, handle, db_connection):
     db_connection.commit()
 
 
-def loop(serial_connection, db_connection, logger):
+def loop(config, serial_connection, db_connection, logger):
+    known_devices = config["known_devices"][config["active_location"]]
     while True:
         logger.info("(Re-)Starting receiver loop")
 
         data = serial_connection.receive_blocking()
         
         if data is None:
-            logger.info("Received no data")
+            logger.info("Didn't receive data")
             continue
 
         logger.info(data)
 
         try:
             if data.device.id_string not in known_devices:
-                logger.info(f"Unknown device with id {device_id} and type {device_type}, ignoring")
+                logger.info(f"Unknown device with id '{device_id}' and type '{device_type}', ignoring")
                 continue
         except:
-            logger.info("Device ID not found, likely no SensorEvent, ignoring")
+            logger.info("Device ID not found, likely not a 'SensorEvent', ignoring")
             continue
 
         handle = known_devices[data.device.id_string]["handle"]
@@ -78,35 +72,73 @@ def loop(serial_connection, db_connection, logger):
         add_data_to_db(data, handle, db_connection)
 
 
+def write_pid_file(pid_file_path, logger):
+    if os.path.exists(pid_file_path):
+        with open(pid_file_path, "r") as pid_file:
+            pid = pid_file.read()
+            logger.error(f"Possibly already running with PID {pid}, exiting")
+        sys.exit(1)
+    with open(path, "w") as pid_file:
+        pid_file.write(str(os.getpid()))
+
+
+def load_config(config_file_path, logger):
+    with open(config_file_path, "r") as f:
+        config = yaml.safe_load(f.read())
+    logger.info(f"Loaded configuration from '{config_file_path}'")
+
+    return config
+
+
 if __name__ == "__main__":
-    logger = logging.getLogger("weather-logger-receiver")
+    # logger setup
     logging.basicConfig(format='%(asctime)-2s %(levelname)-8s %(message)s',
                         datefmt='%Y-%m-%dT%H:%M:%S',
                         level=logging.INFO)
+    logger = logging.getLogger("weather-logger-receiver")
 
-    assert len(sys.argv) == 2
-    location = sys.argv[1]
-    known_devices = load_known_devices(location=location)
-    logger.info(f"Loaded known devices for location {location}")
+    # load configuration
+    if len(sys.argv) != 2:
+        logger.error("Missing path to configuration file, exiting")
+        sys.exit(1)
+    config_file_path = sys.argv[1]
+    config = load_config(config_file_path, logger)
 
-    db_connection = setup_database()
-    logger.info("Set up database")
+    # get known devices
+    active_location = config["active_location"]
+    known_devices = config["locations"][active_location]
+    logger.info(f"Loaded known devices for location '{active_location}'")
 
-    serial_connection = setup_serial()
-    logger.info("Set up serial connection")
+    # write pid file
+    write_pid_file(config["pid_file_path"], logger)
+    logger.info("Wrote PID file to '{config{'pid_file_path']}'")
 
+    # database setup
+    db_connection = setup_database(config["database_path"], logger)
+    logger.info("Set up database '{config['database_path']}'")
+
+    # serial connection setup
+    serial_connection = setup_serial(config["device_path"])
+    logger.info("Set up serial connection to '{config['device_path']}'")
+
+    # handle shutdown
     def shutdown(*args):
         logger.info("Shutting down")
         serial_connection.close()
         db_connection.close()
+        try:
+            os.remove(config["pid_file_path"])
+        except FileNotFoundError:
+            pass
         sys.exit(0)
 
     signal.signal(signal.SIGINT, shutdown)
     signal.signal(signal.SIGTERM, shutdown)
 
+    # start main loop
     try:
-        loop(serial_connection, db_connection, logger)
+        loop(known_devices, serial_connection, db_connection, logger)
     except Exception as e:
-        logger.error(f"Exception: {e}")
+        logger.error(f"Exception: '{e}'")
     finally:
-        shutdown(serial_connection, db_connection, logger)
+        shutdown(config, serial_connection, db_connection, logger)