Files
DataLogger-Generic/daq/taglogger.py
Patrick McDonagh 61f90ec04a formatting changes
2018-02-01 11:57:33 -06:00

227 lines
8.5 KiB
Python

"""
Tag Logger.
Created on April 7, 2016
@author: Patrick McDonagh
@description: Continuously loops through a list of tags to store values from a PLC
"""
import traceback
import time
import json
import requests
from requests.packages.urllib3.exceptions import InsecureRequestWarning
from pycomm.ab_comm.clx import Driver as ClxDriver
from pycomm.cip.cip_base import CommError
requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
# DEFAULTS
DB_ADDRESS = "web_db"
DB_URL = "https://{}:5000".format(DB_ADDRESS)
SCAN_RATE = 30 # seconds
SAVE_ALL = "test" # use True, False, or any string
PLC_HANDSHAKE_TAGS = {}
LAST_HANDSHAKE_TIME = 0
TAG_STORE = {}
TAG_LIST = []
HANDSHAKE_LIST = []
DEVICE_TYPES = {}
def read_from_plc(addr, tag):
"""Read a value from a PLC."""
addr = str(addr)
tag = str(tag)
clx = ClxDriver()
if clx.open(addr):
try:
return clx.read_tag(tag)
except Exception:
print("ERROR RETRIEVING TAG: {} at {}".format(tag, addr))
err = clx.get_status()
clx.close()
print(err)
clx.close()
def write_to_plc(addr, tag, value):
"""Write a value to a tag in the PLC at the specified address."""
present_value = read_from_plc(addr, tag)
if present_value:
clx = ClxDriver()
if clx.open(addr):
try:
clx.write_tag(tag, value, present_value[1])
clx.close()
return True
except Exception:
print("ERROR WRITING TAG: {} at {}".format(tag, addr))
err = clx.get_status()
clx.close()
print(err)
return False
clx.close()
return False
def store_tag(tag):
"""Store the value of a tag in the web_db."""
# global DB_URL
url = "{}/api/tag_vals".format(DB_URL)
tag_val_obj = {
"tag_id": tag['id'],
"value": tag['last_stored']
}
headers = {"Content-Type": "application/json"}
r = requests.post(url, data=json.dumps(tag_val_obj), headers=headers, verify=False)
return r.status_code == 200
def load_data():
"""Load configuration data from the web server."""
global DB_URL, SCAN_RATE, SAVE_ALL, TAG_LIST, HANDSHAKE_LIST
try:
# Get tags stored in database
url = '{}/api/tags'.format(DB_URL)
get_tag_request = requests.get(url, verify=False)
tags = json.loads(get_tag_request.text)
except Exception as e:
print("Error getting tags: {}".format(e))
time.sleep(10)
main()
try:
# Get device types stored in database
get_device_type_request = requests.get('{}/api/device_types'.format(DB_URL), verify=False)
device_types_json = json.loads(get_device_type_request.text)
for dev_type in device_types_json['objects']:
DEVICE_TYPES[dev_type['id']] = dev_type['device_type']
except Exception as e:
print("Error getting tags: {}".format(e))
time.sleep(10)
main()
try:
config_req = requests.get('{}/api/configs'.format(DB_URL), verify=False)
config_json = json.loads(config_req.text)
config_list = config_json['objects']
if len(config_list) > 0:
for c in config_list:
if c['parameter'] == "scan_rate":
SCAN_RATE = float(c['val'])
elif c['parameter'] == "save_all":
SAVE_ALL = c['val']
except Exception as e:
print("Error getting configs: {}".format(e))
new_tags = [dev_type['name'] for dev_type in tags['objects']]
existing_tags = [dev_type['name'] for dev_type in TAG_LIST]
existing_handshakes = [h['name'] for h in HANDSHAKE_LIST]
tags_to_add = []
handshakes_to_add = []
tags_to_copy = []
handshakes_to_copy = []
for dev_type in new_tags:
this_tag = {}
for n_t in tags['objects']:
if n_t['name'] == dev_type:
this_tag["tag"] = n_t['tag']
this_tag["id"] = n_t["id"]
this_tag["name"] = n_t['name']
this_tag["change_threshold"] = n_t['change_threshold']
this_tag["guarantee_sec"] = n_t['guarantee_sec']
this_tag["ip_address"] = n_t['device']['address']
this_tag["device_type"] = DEVICE_TYPES[n_t['device']['device_type_id']]
this_tag["last_stored"] = 0.0
this_tag["last_store_time"] = 0
if dev_type in existing_tags:
for e_t in TAG_LIST:
if e_t['name'] == dev_type:
this_tag['last_stored'] = e_t['last_stored']
this_tag['last_store_time'] = e_t['last_store_time']
tags_to_copy.append(this_tag)
elif dev_type in existing_handshakes:
for e_h in HANDSHAKE_LIST:
if e_h['name'] == dev_type:
this_tag['last_stored'] = e_h['last_stored']
this_tag['last_store_time'] = e_h['last_store_time']
handshakes_to_copy.append(this_tag)
else:
if n_t['tag_class_id'] == 5:
tags_to_add.append(this_tag)
elif n_t['tag_class_id'] == 6:
handshakes_to_add.append(this_tag)
TAG_LIST = tags_to_add + tags_to_copy
HANDSHAKE_LIST = handshakes_to_add + handshakes_to_copy
def main():
"""Run the main routine."""
global SCAN_RATE, TAG_STORE, DEVICE_TYPES, TAG_LIST, HANDSHAKE_LIST, SAVE_ALL
while True:
load_data()
# print(tag_list)
if len(TAG_LIST + HANDSHAKE_LIST) == 0:
print("No tags configured. Trying again in 10 seconds.")
time.sleep(10)
main()
if len(TAG_LIST) > 0:
for i in range(0, len(TAG_LIST)):
try:
val = read_from_plc(TAG_LIST[i]['ip_address'], TAG_LIST[i]['tag'])[0]
now = time.time()
store_value = abs(val - TAG_LIST[i]['last_stored']) > TAG_LIST[i]['change_threshold']
store_time = (now - TAG_LIST[i]['last_store_time']) > TAG_LIST[i]['guarantee_sec']
if store_value or store_time or (SAVE_ALL == "true"):
store_reason = ""
if store_time:
store_reason = "time delta = {} > {}".format(now - TAG_LIST[i]['last_store_time'],
TAG_LIST[i]['guarantee_sec'])
elif store_value:
store_reason = "value delta = {} > {}".format(abs(val - TAG_LIST[i]['last_stored']),
TAG_LIST[i]['change_threshold'])
elif SAVE_ALL == "true":
store_reason = "save all parameter"
TAG_LIST[i]['last_stored'] = val
TAG_LIST[i]['last_store_time'] = now
store_tag(TAG_LIST[i])
print("Stored {} for {} at {} due to {}".format(val, TAG_LIST[i]['name'], now, store_reason))
except CommError:
print("CommError: Error connecting to {} for {}".format(TAG_LIST[i]['ip_address'],
TAG_LIST[i]['name']))
except TypeError:
print("Error reading {}".format(TAG_LIST[i]['name']))
if len(HANDSHAKE_LIST) > 0:
for h in range(0, len(HANDSHAKE_LIST)):
now = time.time()
if (now - HANDSHAKE_LIST[h]['last_store_time']) > HANDSHAKE_LIST[h]['guarantee_sec']:
try:
write_to_plc(str(HANDSHAKE_LIST[h]['ip_address']), str(HANDSHAKE_LIST[h]['tag']), 1)
HANDSHAKE_LIST[h]['last_store_time'] = now
print("Handshake with {} - {} at {}".format(HANDSHAKE_LIST[h]['ip_address'],
HANDSHAKE_LIST[h]['tag'], now))
except CommError:
print("CommError: Error connecting to {} for {}".format(HANDSHAKE_LIST[h]['ip_address'],
HANDSHAKE_LIST[h]['name']))
except TypeError:
print("Error writing {}".format(TAG_LIST[i]['name']))
time.sleep(SCAN_RATE)
if __name__ == '__main__':
main()