424 lines
17 KiB
Python
424 lines
17 KiB
Python
from pathlib import Path
|
|
from icalendar import Calendar, Event
|
|
import toml, argparse, os, sys, hashlib, json, pytz, os, time
|
|
from dateutil.relativedelta import relativedelta
|
|
from dateutil.rrule import rrulestr
|
|
import datetime as dt
|
|
import time
|
|
from watchdog.observers import Observer
|
|
from watchdog.events import FileSystemEventHandler
|
|
import humanfriendly
|
|
from pathlib import Path
|
|
import argparse, textwrap, logging
|
|
from alert_processor import AlertProcessor
|
|
|
|
def setup_logger(loglevel):
|
|
"""Setup basic logging."""
|
|
loglevel = getattr(logging, loglevel.upper(), None)
|
|
|
|
if not isinstance(loglevel, int):
|
|
raise ValueError('Invalid log level: %s' % loglevel)
|
|
|
|
logging.basicConfig(filename='app.log', filemode='w', format='%(name)s - %(levelname)s - %(message)s')
|
|
logger = logging.getLogger()
|
|
logger.setLevel(loglevel)
|
|
|
|
def parse_args():
|
|
"""Parse command line arguments."""
|
|
parser = argparse.ArgumentParser(description="A simple calendar alerting daemon written in Python")
|
|
parser.add_argument('--config', type=str, help='Path to config file. Must be .toml')
|
|
parser.add_argument('--loglevel', choices=['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'], default='INFO', help='Set the logging level')
|
|
args = parser.parse_args()
|
|
if args.config is None:
|
|
logging.error("No config file provided. Please use --config path_to_config.toml")
|
|
sys.exit(1)
|
|
return args
|
|
|
|
def read_file(filename):
|
|
try:
|
|
return Path(filename).read_text()
|
|
except FileNotFoundError as e:
|
|
logging.error("Error: The specified file does not exist.")
|
|
sys.exit(1)
|
|
|
|
def parse_toml(content):
|
|
try:
|
|
return toml.loads(content)
|
|
except Exception as e:
|
|
logging.error("Error: Failed to parse TOML file.")
|
|
sys.exit(1)
|
|
|
|
def calculate_event_hash(event):
|
|
return hashlib.md5(json.dumps(event, sort_keys=True, cls=DateTimeEncoder).encode()).hexdigest()
|
|
|
|
class DateTimeEncoder(json.JSONEncoder):
|
|
def default(self, o):
|
|
if isinstance(o, (dt.datetime, dt.timedelta)):
|
|
return str(o) # Convert the datetime or timedelta object to a string
|
|
return super().default(o)
|
|
|
|
class FileChangeHandler(FileSystemEventHandler):
|
|
"""
|
|
`FileChangeHandler` is a custom event handler for the
|
|
`watchdog.observers.Observer` class that handles file system events such as
|
|
file modifications, deletions and creations.
|
|
"""
|
|
def __init__(self, event_list):
|
|
self.calendar_parser = CalendarParser()
|
|
self.event_list = event_list
|
|
|
|
def on_modified(self, event):
|
|
logging.debug(f"File modified: {event.src_path}")
|
|
if not event.is_directory:
|
|
try:
|
|
with open(event.src_path, 'r') as f:
|
|
cal_str = f.read()
|
|
except Exception as e:
|
|
logging.error(f"Not a valid file: {event.src_path}. Error: {e}")
|
|
return
|
|
|
|
try:
|
|
event_dict = self.calendar_parser.parse_calendar(cal_str) # Use the instance to call parse_calendar method
|
|
except Exception as e:
|
|
logging.error(f"Failed to parse calendar event at: {event.src_path}. Error: {e}")
|
|
return
|
|
|
|
self.handle_modified(old_event=None, event_dict=event_dict)
|
|
|
|
def on_deleted(self, event):
|
|
logging.debug(f"File deleted: {event.src_path}")
|
|
if not event.is_directory:
|
|
uid = os.path.splitext(os.path.basename(event.src_path))[0] # Get the UID from the file path without extension
|
|
|
|
self.handle_modified(old_event=None, event_dict={"uid": uid}, remove=True)
|
|
|
|
def on_created(self, event):
|
|
logging.debug(f"File created: {event.src_path}")
|
|
if not event.is_directory:
|
|
try:
|
|
with open(event.src_path, 'r') as f:
|
|
cal_str = f.read()
|
|
except Exception as e:
|
|
logging.error(f"Not a valid file: {event.src_path}. Error: {e}")
|
|
return
|
|
|
|
try:
|
|
event_dict = self.calendar_parser.parse_calendar(cal_str) # Use the instance to call parse_calendar method
|
|
except Exception as e:
|
|
logging.error(f"Failed to parse calendar event at: {event.src_path}. Error: {e}")
|
|
return
|
|
|
|
self.handle_modified(old_event=None, event_dict=event_dict)
|
|
|
|
def handle_modified(self, old_event, event_dict, remove=False):
|
|
if not remove:
|
|
for i, old_event in enumerate(self.event_list):
|
|
if old_event["uid"] == event_dict["uid"]:
|
|
old_hash = old_event["hash"]
|
|
|
|
new_hash = calculate_event_hash(event_dict)
|
|
if new_hash != old_hash:
|
|
logging.debug(f"Event with UID {old_event['uid']} has been modified or deleted")
|
|
self.event_list[i] = event_dict
|
|
break
|
|
else:
|
|
self.event_list.append(event_dict)
|
|
else: # If remove is True, remove the event from the list
|
|
for i, old_event in enumerate(self.event_list):
|
|
if old_event["uid"] == event_dict["uid"]:
|
|
logging.debug(f"Event with UID {old_event['uid']} has been deleted")
|
|
|
|
del self.event_list[i]
|
|
break
|
|
|
|
class RecurringEventGenerator:
|
|
"""
|
|
A class to generate recurring events based on a start date and a recurrence rule.
|
|
"""
|
|
def __init__(self, dtstart, rrule):
|
|
self.dtstart = dtstart
|
|
self.rrule = rrule
|
|
self.recur_info = {
|
|
"recur_dates": [dtstart],
|
|
"infinite_recur": False,
|
|
"recur_freq": None,
|
|
"recur_interval": None,
|
|
"n_recur_dates_left": 1
|
|
}
|
|
|
|
def generate(self):
|
|
"""
|
|
"""
|
|
if self.rrule is None:
|
|
return self.recur_info
|
|
|
|
rule_str = "RRULE:{}".format(self.rrule.to_ical().decode('utf-8'))
|
|
start_date = self.dtstart
|
|
infinite_recur = False
|
|
freq = self.rrule.get('FREQ')[0]
|
|
count = self.rrule.get("COUNT")
|
|
interval = self.rrule.get('INTERVAL')[0]
|
|
until = self.rrule.get('UNTIL')
|
|
current_date = dt.datetime.now().replace(tzinfo=pytz.UTC)
|
|
|
|
if count is None or until is not None:
|
|
# If there is no COUNT value in RRULE, we need to manually calculate
|
|
# the dates else rrulestr method will return a very large number of
|
|
# values. Here we iterate from the start_date to the current_date based
|
|
# on the interval, then add an arbitrary number of days to that (here
|
|
# it's 10).
|
|
|
|
delta = None
|
|
|
|
if freq == "DAILY":
|
|
delta = relativedelta(days=interval)
|
|
elif freq == "MONTHLY":
|
|
delta = relativedelta(months=interval)
|
|
elif freq == "YEARLY":
|
|
delta = relativedelta(years=interval)
|
|
|
|
count = 0
|
|
origin_date = start_date
|
|
while origin_date < current_date:
|
|
count += interval
|
|
origin_date += delta*interval
|
|
|
|
rule_str += ";COUNT={}".format(count+10)
|
|
infinite_recur = True
|
|
|
|
ruleset = rrulestr(rule_str, dtstart=start_date)
|
|
|
|
recur_dates = [None]
|
|
n_recur = None
|
|
dates = list(ruleset) # Generate future dates according to the rules
|
|
recur_dates = [i for i in dates if i >= current_date]
|
|
n_recur = "inf" if infinite_recur is True else len(recur_dates)
|
|
|
|
self.recur_info["recur_dates"] = recur_dates
|
|
self.recur_info["infinite_recur"] = infinite_recur
|
|
self.recur_info["recur_freq"] = freq
|
|
self.recur_info["recur_interval"] = interval
|
|
self.recur_info["n_recur_dates_left"] = n_recur
|
|
|
|
return self.recur_info
|
|
|
|
class CalendarParser:
|
|
def parse_calendar(self, cal_str):
|
|
"""
|
|
Parse a calendar string and process each event.
|
|
"""
|
|
# Parse the calendar
|
|
cal = self.parse_icalendar(cal_str)
|
|
|
|
# Iterate over each event in the calendar
|
|
for event in cal.walk('vevent'):
|
|
event_dict = self.process_event(event)
|
|
dtstart = self.dtstart_to_datetime(event_dict["dtstart"].dt)
|
|
|
|
generator = RecurringEventGenerator(dtstart, event_dict["rrule"])
|
|
recur_info = generator.generate()
|
|
event_dates = self.remove_exdates(event_dict["exdate"], recur_info["recur_dates"])
|
|
|
|
valarms = self.process_valarm(event)
|
|
|
|
event_dict = {
|
|
"uid": str(event_dict["uid"]),
|
|
"dtstart": dtstart,
|
|
"summary": event_dict["summary"],
|
|
"description": event_dict["description"],
|
|
"location": event_dict["location"],
|
|
"event_dates": event_dates,
|
|
"recur_info": "Recur freq: {}, Recur interval: {}, N dates left: {}".format(
|
|
recur_info["recur_freq"],
|
|
recur_info["recur_interval"],
|
|
recur_info["n_recur_dates_left"]
|
|
),
|
|
"valarms": valarms,
|
|
"alert_history": []
|
|
}
|
|
try:
|
|
new_hash = calculate_event_hash(event_dict) # Calculate the hash of the event dictionary
|
|
except Exception as e:
|
|
raise RuntimeError("Error calculating event hash")
|
|
event_dict["hash"] = new_hash # Store the hash in the event dictionary
|
|
return event_dict
|
|
|
|
def parse_icalendar(self, cal_str):
|
|
"""
|
|
Parse a calendar string into an iCalendar object.
|
|
"""
|
|
try:
|
|
return Calendar.from_ical(cal_str)
|
|
except Exception as e:
|
|
raise RuntimeError("Error parsing calendar.")
|
|
|
|
def process_event(self, event):
|
|
"""
|
|
Process an event from a parsed calendar and extract relevant information.
|
|
"""
|
|
event_info = {
|
|
"uid": None,
|
|
"dtstart": "",
|
|
"exdate": [],
|
|
"summary": None,
|
|
"description": None,
|
|
"location": None,
|
|
"rrule": None
|
|
}
|
|
|
|
# Catch errors for missing components
|
|
for info in event_info:
|
|
try:
|
|
event_info[info] = event[info]
|
|
except Exception:
|
|
pass
|
|
return event_info
|
|
|
|
def dtstart_to_datetime(self, dtstart):
|
|
"""
|
|
Convert a date or datetime object into a datetime object with UTC timezone.
|
|
"""
|
|
# Ensure dates are always as datetime
|
|
try:
|
|
if isinstance(dtstart, dt.datetime):
|
|
return dtstart.replace(tzinfo=pytz.UTC)
|
|
else:
|
|
return dt.datetime.combine(dtstart, dt.time.min).replace(tzinfo=pytz.UTC)
|
|
except Exception as e:
|
|
raise RuntimeError("Error converting dtstart to datetime.")
|
|
|
|
def remove_exdates(self, exdates, recur_dates):
|
|
"""
|
|
Remove dates from a list of recurring event dates that are in the exdate list.
|
|
"""
|
|
if exdates != []:
|
|
try:
|
|
if isinstance(exdates, list):
|
|
exdates = [i.dts[0].dt.replace(tzinfo=pytz.UTC) for i in exdates]
|
|
else:
|
|
exdates = [exdates.dts[0].dt.replace(tzinfo=pytz.UTC)]
|
|
return [i for i in recur_dates if i not in exdates]
|
|
except Exception as e:
|
|
raise RuntimeError("Error processing exdates.")
|
|
else:
|
|
return recur_dates
|
|
|
|
def process_valarm(self, event):
|
|
"""
|
|
Process VALARM components from an iCalendar event and extract trigger times.
|
|
"""
|
|
valarms = []
|
|
for subcomponent in event.walk("valarm"):
|
|
valarm = Event.from_ical(subcomponent.to_ical())
|
|
timedelta = valarm["trigger"].dt
|
|
valarms.append(timedelta)
|
|
return valarms
|
|
|
|
def get_next_alert(event, current_time):
|
|
"""
|
|
Returns the next alert that should be processed based on the current time.
|
|
"""
|
|
event_dates = event["event_dates"]
|
|
valarm_deltas = event["valarms"]
|
|
if event_dates == [] or event_dates is None or current_time > event_dates[-1]:
|
|
return None, None
|
|
next_event = [i for i in event_dates if i >= current_time][0]
|
|
next_alert_list = [next_event + i for i in valarm_deltas if next_event + i >= current_time]
|
|
if len(next_alert_list) == 0:
|
|
next_alert = next_event
|
|
else:
|
|
next_alert = min(next_alert_list)
|
|
return next_alert - dt.timedelta(seconds=5), next_event
|
|
|
|
def process_alert(current_time, next_alert, next_event, event, config):
|
|
"""
|
|
Processes a given alert and passes it to a messaging client.
|
|
"""
|
|
if current_time >= next_alert and current_time < next_alert + dt.timedelta(seconds=15):
|
|
if len(event["alert_history"]) == 0:
|
|
logging.debug(f"First alert for '{event['summary']}' detected")
|
|
event["alert_history"] = [{"timestamp_alert_triggered": current_time, "alert_defintition_time": next_alert}]
|
|
elif next_alert in [i["alert_defintition_time"] for i in event["alert_history"]]:
|
|
return
|
|
else:
|
|
logging.debug(f"Posting alert for {event['summary']}!")
|
|
event["alert_history"].append({"timestamp_alert_triggered": current_time, "alert_defintition_time": next_alert})
|
|
try:
|
|
processor = AlertProcessor(config)
|
|
processor.send_email(event, next_alert, next_event)
|
|
except Exception as e:
|
|
raise RuntimeError("Error sending alert for event.")
|
|
#processor.send_xmpp(event, next_alert, next_event)
|
|
|
|
with open("alert_history", 'a') as f:
|
|
f.write(str(event))
|
|
return
|
|
|
|
def main():
|
|
# Parse args and config
|
|
args = parse_args()
|
|
content = read_file(args.config)
|
|
config = parse_toml(content)
|
|
|
|
# Get calendar dir
|
|
cal_dir = Path(config["app"]["calendar_dir"])
|
|
if not cal_dir.is_dir():
|
|
print(f"The provided path to .ics files does not exist: '{cal_dir}'")
|
|
sys.exit(1) # Exit with error code
|
|
|
|
#Parse calendar events
|
|
calendar_parser = CalendarParser()
|
|
files = list(cal_dir.glob('*.ics'))
|
|
event_list = [] # List to hold dictionaries for each event
|
|
for file in files:
|
|
with open(file, 'r') as f:
|
|
cal_str = f.read()
|
|
try:
|
|
event_dict = calendar_parser.parse_calendar(cal_str)
|
|
except Exception:
|
|
logging.error(f"Error parsing event, skipping. {file}")
|
|
continue
|
|
event_list.append(event_dict)
|
|
|
|
#Start file handler to detect changes to calendar dir
|
|
observer = Observer()
|
|
handler = FileChangeHandler(event_list) # Pass event_list here
|
|
observer.schedule(handler, cal_dir, recursive=True)
|
|
observer.start()
|
|
|
|
#Start main loop
|
|
try:
|
|
while True:
|
|
with open("status", 'w') as f:
|
|
#Refresh the status file
|
|
f.write("")
|
|
current_time = dt.datetime.now().replace(tzinfo=pytz.UTC)
|
|
for event in event_list:
|
|
next_alert, next_event = get_next_alert(event, current_time)
|
|
if next_alert == None:
|
|
continue
|
|
event_delta = next_alert-current_time
|
|
total_seconds = event_delta.total_seconds()
|
|
human_readable_time = humanfriendly.format_timespan(total_seconds)
|
|
monitor_status = f"""\
|
|
Current time: {current_time}
|
|
Monitoring: {event["summary"]}
|
|
Event date: {next_event}
|
|
Recur Dates: {[str(i) for i in event["event_dates"]]}
|
|
Next alert on: {next_alert} in {human_readable_time}
|
|
Recur info: {event["recur_info"]}
|
|
Alert history: {event["alert_history"]}\n"""
|
|
monitor_status = textwrap.dedent(monitor_status)
|
|
with open("status", 'a') as f:
|
|
# Write the output to the file
|
|
f.write(monitor_status)
|
|
f.write("\n")
|
|
process_alert(current_time, next_alert, next_event, event, config)
|
|
time.sleep(1)
|
|
except KeyboardInterrupt:
|
|
observer.stop()
|
|
observer.join()
|
|
|
|
if __name__ == "__main__":
|
|
main()
|