Dialga: call function in the future

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If you ever have the need to run a Python function at a specific time, or periodically. This might come handy.

import asyncio
from datetime import datetime

from dialga import call_at, call_after

loop = asyncio.get_event_loop()

# This function will be call at 11:05 everyday as long that the loop is still running
@call_at(loop=loop, repeated=True, hour=11, minute=5)
def show_actual_runtime(name: str):
    print(f"Actual time of {name}:", datetime.strftime(datetime.now(), "%y-%m-%d %H:%M:%S"))


# This function will be call after every 10 minutes as long as the loop is still running
@call_after(loop=loop, repeated=True, minutes=10)
def show_current_runtime(name: str):
    print(f"Current time of {name}:", datetime.strftime(datetime.now(), "%y-%m-%d %H:%M:%S"))

show_actual_runtime(name="call_now")
show_current_runtime(name="call_now")

show_actual_runtime.promise(name="call_at")
show_current_runtime.promise(name="call_after")

loop.run_forever()

Another way to run an application:

from typing import *
from datetime import datetime
from dialga import Scheduler, call_at, call_after

scheduler = Scheduler()

now = datetime.now()

@scheduler.schedule(call_at, hour=now.hour, minute=now.minute + 5)
def five_minute_from_now():
    print("Five minute from start")
    print("Start time:", datetime.strftime(now, "%y-%m-%d %H:%M:%S"))
    print("End time:", datetime.strftime(datetime.now(), "%y-%m-%d %H:%M:%S"))


@scheduler.schedule(call_after, minutes=1)
def one_minute_from_now():
    print("One minute from start")
    print("Start time:", datetime.strftime(now, "%y-%m-%d %H:%M:%S"))
    print("End time:", datetime.strftime(datetime.now(), "%y-%m-%d %H:%M:%S"))

scheduler.run()

Or another way:

• Call at:

from datetime import datetime
from dialga import schedulable

@schedulable
def print_message(msg: str):
    now = datetime.now()
    print(now, msg)
    return now
    
print(datetime.now())
task = print_message.at(hour=17, minute=32).call('17:32')

print_message('now')
print(task.get_result())

• Call after:

from datetime import datetime
from dialga import schedulable

@schedulable
def print_message(msg: str):
    now = datetime.now()
    print(now, msg)
    return now
    
print(datetime.now())
task = print_message.after(seconds=1).call('1 second later')

print_message('now')
print(task.get_result())

The dialga module is built upon two main function.

• call_after: call the function after some time

def call_after(
    loop: asyncio.AbstractEventLoop = None, 
    repeated: bool = False, # Is the function called repeatly
    **timedetail # Is the parameters of datetime.timedelta
):
    ...

• call_at: call the function at specified time match the configuration

def call_at(
    loop: asyncio.AbstractEventLoop = None, 
    repeated: bool = False, # Is the function called repeatly
    **timedetail # Will be explained below
):
    ...

timedetail includes these parameters: year, month, week, weekday, day, hour, minute, second, all with same format.

• None: ignore
• int: specific value
• (start, end, [step]): value in range(start, end, [step])
• [int, ...]: value in list

Note:

• a tuple in list is still considered as range and will be expanded.
• week has value from 1 -> 5
• weekday has value from 1 -> 7, monday -> sunday, mon -> sun, starts from monday
• hour has value from 0 -> 23
• minute and second hav value from 0 -> 59
• If no suitable time found, the function won't be called