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.
Related
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.
I have a script of a bot deployed on azure that has to be always running. it's a python bot that tracks Twitter mentions in real time by opening a stream listener.
The script fails every once in a while for reasons not directly related to the script (timeouts, connection errors, etc). After searching for answers around here I found this piece of code as the best workaround for restarting the script every time it fails.
#!/usr/bin/env python3.7
import os
def run_bot():
while True:
try:
os.system("test_bot.py start")
except:
pass
if __name__ == "__main__":
run_bot()
I am logging all error messages to learn the reasons why it fails but I think there just be a better way to achieve the same, I would very much appreciate some hints.
So this is wrong way to run a script, you are running it in while loop forever.
A better way is either to schedule your main script in a cron job: Execute Python script via crontab
You can schedule this job to run every min, or hour or a specific time of the day, up to you.
If you wish to run something always, like a system monitor. Then you can run that part inside a while True loop that is fine. Like a loop which checks temperature every 5 secs writes to a file and sleep for 5 secs.
sample sudo code for the script: prog.py
while True:
log_temp()
time.sleep(5secs)
But if the script fails then schedule something to restart the script. Dont start the script inside another while loop.
Something like this: https://unix.stackexchange.com/questions/107939/how-to-restart-the-python-script-automatically-if-it-is-killed-or-dies
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
I have done many research on the forum but I didn't find a clear answer to my question.
I have created a python code which extracts data from a website and put it in a SQL database (with SQLITE).
Now, I would like to make it run 24 hours a day on a server so that it collects data at each moment.
Although I know how to code, I don't have a broad knowledge of IT in general.
Would you know by chance how to solve my problem ?
Edit: I was more thinking about putting my scripts on a cloud server to make it run instead of running it directly from my pc.
Thank you very much.
Lcs
I can think of two options:
1) You use a simple "while true" and "wait" in python, so the script is running constantly.
import time
while True:
# Code
time.sleep(5) # goes to sleep for 5 seconds
You can also do this in shell script (infinite loop+sleep) and then run the program when you want.
2) You can use cronjobs to run the pytho script. You basically have the script the will scrap the website and it will be launched every X seconds/minutes/hours. You can read more about how to use cronjobs in Google
Depends on what system you are using (Unix or windows) you can use either:
1. Windows Task Scheduler for Windows
2. Crontab for Unix
I'm used to using Windows Server 2003 and to run my Python scripts as a scheduled task I simply followed the below steps: Opened Scheduled Tasks > Add Scheduled Task > Next > select Python > Next > Name the task, daily > supplied start time > supplied username and password to run the task.
Server 2008 looks a bit different but after opening Task Scheduler, I first chose Create basic task > gave it a name > chose Daily > start time and date > start program > and this is where I get confused.. I'm now asked to browse for Program/script (which i thought would be my actual python script) and I can Add arguments and Start in (both are optional). How do I tell the Task Scheduler that the program is a Python program? Server 2003 gave me a list for that. If I setup the Task the way I just described and run it, my task simply opens in Notepad and never runs.
Thank you for any help.
You could set python.exe as the program, and pass your script to it as an argument.