Develop Reference

How to run a python script after an x amount of time it has just finished?

I want to be able to run my python script which scans for something related to cryptocurrencies 1 minute after the same script has just been complete. Is this possible? Or could I maybe set a limit before the loop repeats itself or something?
The code I have isn't something I am willing to share due to its sensitive nature. It is a trading bot.

You have a few solutions:
Use a cron job if you are on a unix like platform (you can use this for the syntax, or man cron in the terminal to learn more about it)
Create a long running python script that sleeps for one minute before executing your logic again. Something like this:
import time
while True:
# execute code here
time.sleep(60)

If you are running it on Windows platform ,
You can create a batch file to run your script in cmd using the following command:
start "" "path_to_python.exe" "path_to_python_script"
then create a task in windows task scheduler .
You can refer
https://dev.to/tharindadilshan/running-a-python-script-every-x-minutes-in-windows-10-3nm9 . It might helps.

Python restart file on windows or linux

I currently have a big long file that queries a webpage to build a dictionary. I'd like this file to restart at 4am every day as the webpage will have updated with fresh info. What do I need to put inside my while True: loop?
Current status:
##Various Imports
##Selenium code to get details
##Dictionary Compile
while True:
now = datetime.datetime.now()
current_time = now.strftime("%H:%M:%S")
if current_time == ("04:00:00"):
##The Code to Restart the process goes here
else:
#Other Stuff happens with the dictionary
Building and testing on windows but will ultimately run on a Raspberry Pi

I would suggest you make the script simply get the information from the web page then do whatever it needs to do with your dictionary and end. Only one time. Then you can schedule this script to run at 4:00 AM every day with Windows Task Scheduler or with a Cron Job on linux. Here is a link on how to set up a cron job to run a python script.

If you want the functionality of a cron job in Python you could use the schedule library. It looks like it has support to keep the script running and then restart at 4AM. More can be read on this StackOverflow Question.

How to schedule a script to run periodically?

I have a task to write a Python script which has to parse a web-page once a week. I wrote the script but do not know how can I make it to work once a week. Could someone share an advice and write possible solution?

Have a look at cron. Its not python, but fits the job much better in my opinion. For example:
#weekly python path/to/your/script
A similar question was discussed here.

Whether the script itself should repeat a task periodically usually depends on how frequently the task should repeat. Once a week is usually better left to a scheduling tool like cron or at.
However, a simple method inside the script is to wrap your main logic in a loop that sleeps until the next desired starting time, then let the script run continuously. (Note that a script cannot reliably restart itself, or showing how to do so is beyond the scope of this question. Prefer an external solution.)
Instead of
def main():
...
if __name__ == '__main__':
main()
use
import tim
one_week = 7 * 24 * 3600 # Seconds in a week
def main():
...
if __name__ == '__main__':
while True:
start = time.time()
main()
stop = time.time()
elapsed = stop - start
time.sleep(one_week - elapsed)

Are you planning to run it locally? Are you working with a virtual environment?
Task scheduler option
If you are running it locally, you can use Task scheduler from Windows. Setting up the task can be a bit tricky I found, so here is an overview:
Open Task Scheduler > Create Task (on right actions menu)
In tab "General" name the task
In tab "Triggers" define your triggers (i.e. when you want to schedule the tasks)
In tab "Actions" press on new > Start a program. Under Program/script point to the location (full path) of your python executable (python.exe). If you are working with a virtual environment it is typically in venv\Scripts\python.exe. The full path would be C:\your_workspace_folder\venv\Scripts\python.exe. Otherwise it will be most likely in your Program Files.
Within the same tab, under Add arguments, enter the full path to your python script. For instance: "C:\your_workspace_folder\main.py" (note that you need the ").
Press Ok and save your task.
Debugging
To test if your schedule works you could right click on the task in Task scheduler and press on Run. However, then you don't see the logs of what is happening. I recommend therefore to open a terminal (eg cmd) and type the following:
C:\your_workspace_folder\venv\Scripts\python.exe "C:\your_workspace_folder\main.py"
This allows you to see the full trace of your code and if its running properly. Typical errors that occur are related to file paths (eg if you are not using the full path but a relative path).
Sleeping mode
It can happen that some of the tasks do not run because you don't have administrator privileges and your computer goes in sleeping mode. What I found as a workaround is to keep the computer from going into sleeping mode using a .vbs script. Simply open notepad and create a new file named idle.vbs (extension should be .vbs so make sure you select all programs). In there paste the following code:
Dim objResult
Set objShell = WScript.CreateObject("WScript.Shell")
Do While True
objResult = objShell.sendkeys("{NUMLOCK}{NUMLOCK}")
Wscript.Sleep (60000)
Loop

Scheduling some python tasks

I am trying to schedule some tasks using python...
Here is the whole project:
I have online classes on zoom which I want to automatically record. (I can't wake up on time). I have the invite link to the meeting. The time and date of the meeting are mentioned in it.
I have written the python script to extract the message. Let's call this script A.
I have also written a script to click on the link so that the zoom meeting opens. Let's call this script B.
I need to run the scripts in this order:
I manually run script A at let's say 12:00 AM in the night(morning). By that time, the teachers would have sent the invite link message.
Based on the information that was extracted, I want to automatically run script B and start the OBS recording. A way to end the recording after the meeting has ended would also be appreciated. (or I could just record for 1 hour).
I just need to find a way to automatically start recording from OBS screen recorder at the time mentioned in the message. (possibly in script B only)
How do I go about it?

You could use the windows task scheduler.
scriptA extracts the start time for the online task, sleeps until the correct time (using time.sleep()) and then uses subprocess.Popen to start script B at the appropriate time.
For example; simply starting script B, discarding any output (assuming it resides in the current working directory):
import subprocess
subprocess.Popen(
['python3', 'scriptB.py'],
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL
)

How do I have a bash script continually run during business hours?

I have a Python program I run at all times of the day that alerts me when something I am looking for online is posted. I want to give this to my employees but I only want to have it email them during business hours.
I have a Ubuntu server and use a .sh. I have a command in crontab that runs on startup.
How do I make my command run from 9-5?

You could create a cronjob that starts the script every 5 minutes (or whatever often you want it to run) and additionally modify the script such that it creates a .lock file which it removes on exiting, but if it encounters it at the beginning it won't do anything (this way you don't have a long-running script active multiple times).