myems-aggregation/virtual_meter_billing.py
import time
from datetime import datetime, timedelta
from decimal import Decimal
import mysql.connector
import config
import tariff
########################################################################################################################
# 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")
try:
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()
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
except Exception as e:
logger.error("Error in step 3 of virtual_meter_billing " + str(e))
# break the for virtual_meter loop
break
############################################################################################################
# Step 4: get tariffs
############################################################################################################
print("Step 4: get tariffs")
tariff_dict = dict()
tariff_dict[virtual_meter['energy_category_id']] = \
tariff.get_energy_category_tariffs(virtual_meter['cost_center_id'],
virtual_meter['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")
aggregated_values = list()
if len(energy_dict) > 0:
for current_datetime_utc in energy_dict.keys():
aggregated_value = dict()
aggregated_value['start_datetime_utc'] = current_datetime_utc
aggregated_value['actual_value'] = None
current_tariff = tariff_dict[virtual_meter['energy_category_id']].get(current_datetime_utc)
current_energy = energy_dict[current_datetime_utc].get(virtual_meter['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):
aggregated_value['actual_value'] = current_energy * current_tariff
aggregated_values.append(aggregated_value)
############################################################################################################
# Step 6: save billing data to billing database
############################################################################################################
print("Step 6: save billing data to billing database")
while len(aggregated_values) > 0:
insert_100 = aggregated_values[:100]
aggregated_values = aggregated_values[100:]
try:
add_values = (" INSERT INTO tbl_virtual_meter_hourly "
" (virtual_meter_id, "
" start_datetime_utc, "
" actual_value) "
" VALUES ")
for aggregated_value in insert_100:
if aggregated_value['actual_value'] is not None and \
isinstance(aggregated_value['actual_value'], Decimal):
add_values += " (" + str(virtual_meter['id']) + ","
add_values += "'" + aggregated_value['start_datetime_utc'].isoformat()[0:19] + "',"
add_values += str(aggregated_value['actual_value']) + "), "
# 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
# end of for virtual_meter loop
if cursor_system_db:
cursor_system_db.close()
if cnx_system_db:
cnx_system_db.close()
if cursor_energy_db:
cursor_energy_db.close()
if cnx_energy_db:
cnx_energy_db.close()
if cursor_billing_db:
cursor_billing_db.close()
if cnx_billing_db:
cnx_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