main.main()

Complexity

Conditions

21

Size

Total Lines	90
Code Lines	59

Duplication

Lines	0
Ratio	0 %

Importance

Changes

0

import json

def main():

    """main"""

    # create logger

    logger = logging.getLogger('myems-modbus-tcp')

    # specifies the lowest-severity log message a logger will handle,

    # where debug is the lowest built-in severity level and critical is the highest built-in severity.

    # For example, if the severity level is INFO, the logger will handle only INFO, WARNING, ERROR, and CRITICAL

    # messages and will ignore DEBUG messages.

    logger.setLevel(logging.ERROR)

    # create file handler which logs messages

    fh = RotatingFileHandler('myems-modbus-tcp.log', maxBytes=1024*1024, backupCount=1)

    # create formatter and add it to the handlers

    formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')

    fh.setFormatter(formatter)

    # add the handlers to logger

    logger.addHandler(fh)


    # Get Data Sources

    while True:

        # TODO: This service has to RESTART to reload latest data sources and this should be fixed

        cnx_system_db = None

        cursor_system_db = None

        try:

            cnx_system_db = mysql.connector.connect(**config.myems_system_db)

            cursor_system_db = cnx_system_db.cursor()

        except Exception as e:

            logger.error("Error in main process " + str(e))

            if cursor_system_db:

                cursor_system_db.close()

            if cnx_system_db:

                cnx_system_db.close()

            # sleep several minutes and continue the outer loop to reload points

            time.sleep(60)

            continue


        # Get data sources by gateway and protocol

        try:

            query = (" SELECT ds.id, ds.name, ds.connection "

                     " FROM tbl_data_sources ds, tbl_gateways g "

                     " WHERE ds.protocol = 'modbus-tcp' AND ds.gateway_id = g.id AND g.id = %s AND g.token = %s "

                     " ORDER BY ds.id ")

            cursor_system_db.execute(query, (config.gateway['id'], config.gateway['token'],))

            rows_data_source = cursor_system_db.fetchall()

        except Exception as e:

            logger.error("Error in main process " + str(e))

            # sleep several minutes and continue the outer loop to reload points

            time.sleep(60)

            continue

        finally:

            if cursor_system_db:

                cursor_system_db.close()

            if cnx_system_db:

                cnx_system_db.close()


        if rows_data_source is None or len(rows_data_source) == 0:

The variable rows_data_source does not seem to be defined for all execution paths.

            logger.error("Data Source Not Found, Wait for minutes to retry.")

            # wait for a while and retry

            time.sleep(60)

            continue

        else:

            # Stop to connect these data sources

            break


    for row_data_source in rows_data_source:

        print("Data Source: ID=%s, Name=%s, Connection=%s " %

              (row_data_source[0], row_data_source[1], row_data_source[2]))


        if row_data_source[2] is None or len(row_data_source[2]) == 0:

            logger.error("Data Source Connection Not Found.")

            continue


        try:

            server = json.loads(row_data_source[2])

        except Exception as e:

            logger.error("Data Source Connection JSON error " + str(e))

            continue


        if 'host' not in server.keys() \

                or 'port' not in server.keys() \

                or server['host'] is None \

                or server['port'] is None \

                or len(server['host']) == 0 \

                or not isinstance(server['port'], int) \

                or server['port'] < 1:

            logger.error("Data Source Connection Invalid.")

            continue


        # fork worker process for each data source

        # todo: how to restart the process if the process terminated unexpectedly

        Process(target=acquisition.process, args=(logger, row_data_source[0], server['host'], server['port'])).start()