epicyon/threads.py

139 lines
4.0 KiB
Python

__filename__ = "threads.py"
__author__ = "Bob Mottram"
__license__ = "AGPL3+"
__version__ = "1.0.0"
__maintainer__ = "Bob Mottram"
__email__ = "bob@freedombone.net"
__status__ = "Production"
import threading
import sys
import trace
import time
import datetime
class threadWithTrace(threading.Thread):
def __init__(self, *args, **keywords):
self.startTime=datetime.datetime.utcnow()
self.isStarted=False
tries=0
while tries<3:
try:
self._args, self._keywords = args, keywords
threading.Thread.__init__(self, *self._args, **self._keywords)
self.killed = False
break
except Exception as e:
print('ERROR: threads.py/__init__ failed - '+str(e))
time.sleep(1)
tries+=1
def start(self):
tries=0
while tries<3:
try:
self.__run_backup = self.run
self.run = self.__run
threading.Thread.start(self)
break
except Exception as e:
print('ERROR: threads.py/start failed - '+str(e))
time.sleep(1)
tries+=1
# note that this is set True even if all tries failed
self.isStarted=True
def __run(self):
tries=0
while tries<3:
try:
sys.settrace(self.globaltrace)
self.__run_backup()
self.run = self.__run_backup
break
except Exception as e:
print('ERROR: threads.py/__run failed - '+str(e))
time.sleep(1)
tries+=1
def globaltrace(self, frame, event, arg):
if event == 'call':
return self.localtrace
else:
return None
def localtrace(self, frame, event, arg):
if self.killed:
if event == 'line':
raise SystemExit()
return self.localtrace
def kill(self):
self.killed = True
def clone(self,fn):
return threadWithTrace(target=fn, \
args=self._args, \
daemon=True)
def removeDormantThreads(baseDir: str,threadsList: [],debug: bool) -> None:
"""Removes threads whose execution has completed
"""
if len(threadsList)==0:
return
dormantThreads=[]
currTime=datetime.datetime.utcnow()
changed=False
# which threads are dormant?
noOfActiveThreads=0
for th in threadsList:
removeThread=False
if th.isStarted:
if not th.is_alive():
if debug:
print('DEBUG: thread is not alive')
removeThread=True
elif (currTime-th.startTime).total_seconds()>60:
if debug:
print('DEBUG: thread timed out')
removeThread=True
if removeThread:
dormantThreads.append(th)
else:
noOfActiveThreads+=1
if debug:
print('DEBUG: '+str(noOfActiveThreads) + ' active threads out of '+str(len(threadsList)))
# remove the dormant threads
dormantCtr=0
for th in dormantThreads:
if debug:
print('DEBUG: Removing dormant thread '+str(dormantCtr))
dormantCtr+=1
threadsList.remove(th)
th.kill()
changed=True
# start scheduled threads
if len(threadsList)<10:
ctr=0
for th in threadsList:
if not th.isStarted:
print('Starting new send thread '+str(ctr))
th.start()
changed=True
break
ctr+=1
if not changed:
return
if debug:
sendLogFilename=baseDir+'/send.csv'
with open(sendLogFilename, "a+") as logFile:
logFile.write(currTime.strftime("%Y-%m-%dT%H:%M:%SZ")+','+str(noOfActiveThreads)+','+str(len(threadsList))+'\n')