crontab usage

20230503
https://stackoverflow.com/questions/48339383/crontab-does-not-run-my-python-script

https://www.jcchouinard.com/python-automation-with-cron-on-mac/

https://unix.stackexchange.com/questions/52330/how-to-redirect-output-to-a-file-from-within-cron

https://crontab.guru/#20_*_*_*_*


Above are severa link that I found could be useful.
The example of crontab job:
0 9 * * * /Path/to/pythonOrShell script >> f.log 2>&1   # only so the stdout and stderr could be correctly output to the f.log
Then you need to allow the privacy requirement of the cronjob.


>>> below is the code that I used to autodownload the picture from APVOD, and set it as the plot of my screen.
```
#!/usr/bin/env python3
import os
import requests
import datetime
import subprocess
import matplotlib.pyplot as plt
#import BeautifulSoup
# Define the URL of the Astronomy Picture of the Day (APOD) website
APOD_URL = "https://apod.nasa.gov/apod/"

# Create a directory to store the downloaded images
IMAGE_DIR = os.path.join(os.path.expanduser("~"), "Pictures", "APOD")
os.makedirs(IMAGE_DIR, exist_ok=True)

# Get the current date in YY-MM-DD format
today = datetime.date.today().strftime("%y-%m-%d")
print(datetime.datetime.now(), today)

# Construct the URL of the APOD image for today
image_url = APOD_URL + "ap" + today.replace("-", "") + ".html"

print(image_url)
# Send a request to the APOD website and get the HTML response
response = requests.get(image_url)

# Extract the URL of the APOD image from the HTML response
image_start = response.text.find('href="image/') + len('href="image/')
## extract the url of the picture today:
# try-1
image_suffix = ['.jpg"', '.png"', '.jpeg"']
for suffix in image_suffix: 
    image_end = response.text.find(suffix)
    print(image_end)
    if (image_end != -1) and (image_end > image_start) and (image_end < image_start + 100):
	    break
        
print('The postion of the image start and end',image_end, image_start)
image_path = response.text[image_start:image_end+4]
#print(image_path)
image_url = APOD_URL +'image/'+ image_path

#print(image_url)

# Download the image from the URL
response = requests.get(image_url)
 
# Save the image to the local directory
image_path = os.path.join(IMAGE_DIR, today + ".jpg")
with open(image_path, "wb") as f:
    f.write(response.content)

# Display the image
# Set the downloaded image as the desktop background
SCRIPT = """/usr/bin/osascript<<END
tell application "Finder"
set desktop picture to POSIX file "%s"
end tell
END"""
subprocess.Popen(SCRIPT%image_path, shell=True)

print('Here, the crontab has runned the code')



```