import time from datetime import datetime, timedelta from decimal import Decimal import mysql.connector import tariff import config ######################################################################################################################## # PROCEDURES # Step 1: get all virtual meters # for each virtual meter in list: # Step 2: get the latest start_datetime_utc # Step 3: get all energy data since the latest start_datetime_utc # Step 4: get tariffs # Step 5: calculate billing by multiplying energy with tariff # Step 6: save billing data to database ######################################################################################################################## def main(logger): while True: # the outermost while loop ################################################################################################################ # Step 1: get all virtual meters ################################################################################################################ 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 step 1.1 of meter_billing " + str(e)) if cursor_system_db: cursor_system_db.close() if cnx_system_db: cnx_system_db.close() # sleep and continue the outermost while loop time.sleep(60) continue print("Connected to MyEMS System Database") virtual_meter_list = list() try: cursor_system_db.execute(" SELECT id, name, energy_category_id, cost_center_id " " FROM tbl_virtual_meters " " ORDER BY id ") rows_virtual_meters = cursor_system_db.fetchall() if rows_virtual_meters is None or len(rows_virtual_meters) == 0: print("Step 1.2: There isn't any virtual meters ") if cursor_system_db: cursor_system_db.close() if cnx_system_db: cnx_system_db.close() # sleep and continue the outermost while loop time.sleep(60) continue for row in rows_virtual_meters: virtual_meter_list.append({"id": row[0], "name": row[1], "energy_category_id": row[2], "cost_center_id": row[3]}) except Exception as e: logger.error("Error in step 1.2 of virtual_meter_billing " + str(e)) if cursor_system_db: cursor_system_db.close() if cnx_system_db: cnx_system_db.close() # sleep and continue the outermost while loop time.sleep(60) continue print("Step 1.2: Got all virtual meters from MyEMS System Database") cnx_energy_db = None cursor_energy_db = None try: cnx_energy_db = mysql.connector.connect(**config.myems_energy_db) cursor_energy_db = cnx_energy_db.cursor() except Exception as e: logger.error("Error in step 1.3 of virtual_meter_billing " + str(e)) if cursor_energy_db: cursor_energy_db.close() if cnx_energy_db: cnx_energy_db.close() if cursor_system_db: cursor_system_db.close() if cnx_system_db: cnx_system_db.close() # sleep and continue the outermost while loop time.sleep(60) continue print("Connected to MyEMS Energy Database") cnx_billing_db = None cursor_billing_db = None try: cnx_billing_db = mysql.connector.connect(**config.myems_billing_db) cursor_billing_db = cnx_billing_db.cursor() except Exception as e: logger.error("Error in step 1.4 of virtual_meter_billing " + str(e)) if cursor_billing_db: cursor_billing_db.close() if cnx_billing_db: cnx_billing_db.close() if cursor_energy_db: cursor_energy_db.close() if cnx_energy_db: cnx_energy_db.close() if cursor_system_db: cursor_system_db.close() if cnx_system_db: cnx_system_db.close() # sleep and continue the outermost while loop time.sleep(60) continue print("Connected to MyEMS Billing Database") for virtual_meter in virtual_meter_list: ############################################################################################################ # Step 2: get the latest start_datetime_utc ############################################################################################################ print("Step 2: get the latest start_datetime_utc from billing database for " + virtual_meter['name']) try: cursor_billing_db.execute(" SELECT MAX(start_datetime_utc) " " FROM tbl_virtual_meter_hourly " " WHERE virtual_meter_id = %s ", (virtual_meter['id'], )) row_datetime = cursor_billing_db.fetchone() start_datetime_utc = datetime.strptime(config.start_datetime_utc, '%Y-%m-%d %H:%M:%S') start_datetime_utc = start_datetime_utc.replace(minute=0, second=0, microsecond=0, tzinfo=None) if row_datetime is not None and len(row_datetime) > 0 and isinstance(row_datetime[0], datetime): # replace second and microsecond with 0 # note: do not replace minute in case of calculating in half hourly start_datetime_utc = row_datetime[0].replace(second=0, microsecond=0, tzinfo=None) # start from the next time slot start_datetime_utc += timedelta(minutes=config.minutes_to_count) print("start_datetime_utc: " + start_datetime_utc.isoformat()[0:19]) except Exception as e: logger.error("Error in step 2 of virtual_meter_billing " + str(e)) # break the for virtual_meter loop break ############################################################################################################ # Step 3: get all energy data since the latest start_datetime_utc ############################################################################################################ print("Step 3: get all energy data since the latest start_datetime_utc") query = (" SELECT start_datetime_utc, actual_value " " FROM tbl_virtual_meter_hourly " " WHERE virtual_meter_id = %s AND start_datetime_utc >= %s " " ORDER BY id ") cursor_energy_db.execute(query, (virtual_meter['id'], start_datetime_utc, )) rows_hourly = cursor_energy_db.fetchall() if rows_hourly is None or len(rows_hourly) == 0: print("Step 3: There isn't any energy input data to calculate. ") # continue the for virtual_meter loop continue energy_dict = dict() energy_category_list = list() energy_category_list.append(virtual_meter['energy_category_id']) end_datetime_utc = start_datetime_utc for row_hourly in rows_hourly: current_datetime_utc = row_hourly[0] actual_value = row_hourly[1] if energy_dict.get(current_datetime_utc) is None: energy_dict[current_datetime_utc] = dict() energy_dict[current_datetime_utc][virtual_meter['energy_category_id']] = actual_value if current_datetime_utc > end_datetime_utc: end_datetime_utc = current_datetime_utc ############################################################################################################ # Step 4: get tariffs ############################################################################################################ print("Step 4: get tariffs") tariff_dict = dict() for energy_category_id in energy_category_list: tariff_dict[energy_category_id] = tariff.get_energy_category_tariffs(virtual_meter['cost_center_id'], energy_category_id, start_datetime_utc, end_datetime_utc) ############################################################################################################ # Step 5: calculate billing by multiplying energy with tariff ############################################################################################################ print("Step 5: calculate billing by multiplying energy with tariff") billing_dict = dict() if len(energy_dict) > 0: for current_datetime_utc in energy_dict.keys(): billing_dict[current_datetime_utc] = dict() for energy_category_id in energy_category_list: current_tariff = tariff_dict[energy_category_id].get(current_datetime_utc) current_energy = energy_dict[current_datetime_utc].get(energy_category_id) if current_tariff is not None \ and isinstance(current_tariff, Decimal) \ and current_energy is not None \ and isinstance(current_energy, Decimal): billing_dict[current_datetime_utc][energy_category_id] = \ current_energy * current_tariff if len(billing_dict[current_datetime_utc]) == 0: del billing_dict[current_datetime_utc] ############################################################################################################ # Step 6: save billing data to billing database ############################################################################################################ print("Step 6: save billing data to billing database") if len(billing_dict) > 0: try: add_values = (" INSERT INTO tbl_virtual_meter_hourly " " (virtual_meter_id, " " start_datetime_utc, " " actual_value) " " VALUES ") for current_datetime_utc in billing_dict: for energy_category_id in energy_category_list: current_billing = billing_dict[current_datetime_utc].get(energy_category_id) if current_billing is not None and isinstance(current_billing, Decimal): add_values += " (" + str(virtual_meter['id']) + "," add_values += "'" + current_datetime_utc.isoformat()[0:19] + "'," add_values += str(billing_dict[current_datetime_utc][energy_category_id]) + "), " print("add_values:" + add_values) # trim ", " at the end of string and then execute cursor_billing_db.execute(add_values[:-2]) cnx_billing_db.commit() except Exception as e: logger.error("Error in step 6 of virtual_meter_billing " + str(e)) # break the for virtual_meter loop break # end of for virtual_meter loop if cnx_system_db: cnx_system_db.close() if cursor_system_db: cursor_system_db.close() if cnx_energy_db: cnx_energy_db.close() if cursor_energy_db: cursor_energy_db.close() if cnx_billing_db: cnx_billing_db.close() if cursor_billing_db: cursor_billing_db.close() print("go to sleep 300 seconds...") time.sleep(300) print("wake from sleep, and continue to work...") # end of the outermost while loop