在Django中使用Huey：如何保持run_huey命令持续运行？

Great question—running background tasks reliably on Ubuntu 18.04 is a common need, and there are a few solid approaches depending on your use case. Let's break this down into two parts: keeping run_huey alive after SSH disconnects, and making it start automatically on system boot.

1. Quick Fix: Use nohup #

If you need a simple, one-off solution, nohup (short for "no hangup") is perfect. It detaches the process from your SSH session and redirects output to a log file so it keeps running even after you disconnect.

Run this command in your Django project directory:

nohup python manage.py run_huey > huey.log 2>&1 &

• > huey.log 2>&1 redirects both standard output and errors to huey.log (you can change the filename if you want).
• The final & sends the process to the background.

To check if it's running:

ps aux | grep run_huey

To stop the process later, use kill <PID> where <PID> is the process ID from the above command.

2. Interactive Control: Use screen or tmux #

If you want to be able to reconnect to the process and monitor its output later, use a terminal multiplexer like screen or tmux.

Using screen:

1. Install it first (if not already installed):

   sudo apt update && sudo apt install screen
   

2. Start a new screen session named "huey":

   screen -S huey
   

3. Run your run_huey command as usual:

   python manage.py run_huey
   

4. Detach from the session without stopping it: press Ctrl + A, then D.
5. Later, to reconnect to the session:

   screen -r huey
   

6. To stop the session entirely, reconnect and press Ctrl + D, or kill the process with kill <PID>.

3. Production-Grade: Use systemd #

For the most reliable setup (especially if you need the process to restart automatically if it crashes), use systemd—Ubuntu 18.04's default init system. This also solves your auto-start-on-reboot need in one go.

Step 1: Create a systemd service file

Open a new service file with nano:

sudo nano /etc/systemd/system/huey.service

Paste the following configuration, replacing placeholders with your actual details:

[Unit]
Description=Huey Task Runner for Django Application
After=network.target  # Wait for network to be ready before starting

[Service]
User=your_username  # Replace with your Ubuntu username
WorkingDirectory=/path/to/your/django/project  # Full path to your Django project root
ExecStart=/path/to/your/python/environment/bin/python manage.py run_huey  # Path to your Python executable (use virtualenv path if you're using one)
Restart=always  # Restart the service if it crashes
RestartSec=5  # Wait 5 seconds before restarting
StandardOutput=journal+console  # Send logs to systemd journal
StandardError=journal+console

[Install]
WantedBy=multi-user.target  # Start when the system reaches multi-user mode

Save and exit nano: press Ctrl + O, then Enter, then Ctrl + X.

Step 2: Enable and start the service

1. Reload systemd to recognize the new service:

   sudo systemctl daemon-reload
   

2. Start the Huey service:

   sudo systemctl start huey
   

3. Verify it's running:

   systemctl status huey
   

If you used the systemd method above, enabling auto-start is just one more command:

sudo systemctl enable huey

This tells systemd to start the Huey service every time the system boots up.

If you're not using systemd (not recommended): #

You can use crontab to run the nohup command on reboot, but this is less reliable than systemd (it won't restart the process if it crashes).

Edit your crontab:

crontab -e

Add this line at the end (replace paths as needed):

@reboot nohup /path/to/python /path/to/manage.py run_huey > /path/to/huey.log 2>&1 &

Save and exit, and the command will run on every system restart.

内容的提问来源于stack exchange，提问作者Valachio