Automate Homebrew updates on macOS using launchd. The update script runs daily at 6:00 AM.

brew_autoupdate.md

Automated Homebrew Updates with launchd on macOS

This Gist provides a script and a launchd configuration file to automatically update Homebrew packages and casks on a daily schedule. It uses the macOS-native launchd system, which is more reliable than cron for systems that may be asleep during a scheduled run.

Setup Instructions

1. Create the Script:

   • Place the update_brew.sh file in a directory within your user's home folder, such as ~/bin/.
   • Make the script executable by running (mkdir -p ~/bin if you do not have this directory):

     chmod +x ~/bin/update_brew.sh

2. Configure the launchd Job:

   • Open the com.user.brewupdate.plist file in a text editor.
   • Find all instances of the placeholder your_username and replace them with your actual macOS username (e.g., /Users/jdoe/).
   • Save the modified file.

3. Install the launchd Agent:

   • Move the edited com.user.brewupdate.plist file into your user's LaunchAgents directory:

     mv com.user.brewupdate.plist ~/Library/LaunchAgents/

4. Load the Job:

   • Load the job into launchd using the following terminal command:

     launchctl load ~/Library/LaunchAgents/com.user.brewupdate.plist

The task is now scheduled to run daily at 6:00 AM. Log files will be created at ~/Library/Logs/brewupdate.log.

To Disable

To stop the automated task, run the following command:

launchctl unload ~/Library/LaunchAgents/com.user.brewupdate.plist

References

Below uses cron which isn't macos native: https://nopnithi.medium.com/effortlessly-automate-homebrew-updates-on-macos-24941d0213d1

com.user.brewupdate.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.user.brewupdate</string>
    
    <key>ProgramArguments</key>
    <array>
        <string>/Users/your_username/bin/update_brew.sh</string>
    </array>
    
    <key>StartCalendarInterval</key>
    <dict>
        <key>Hour</key>
        <integer>6</integer>
        <key>Minute</key>
        <integer>0</integer>
    </dict>
    
    <key>StandardOutPath</key>
    <string>/Users/your_username/Library/Logs/brewupdate.log</string>
    
    <key>StandardErrorPath</key>
    <string>/Users/your_username/Library/Logs/brewupdate.log</string>
    
    <key>RunAtLoad</key>
    <true/>
    
    <key>AbandonProcessGroup</key>
    <true/>
</dict>
</plist>

update_brew.sh

#!/bin/bash
# Ensure Homebrew is in the PATH for the script
export PATH="/opt/homebrew/bin:$PATH"

echo "--- Starting Homebrew Update: $(date) ---"

# Update Homebrew package lists
brew update

# Upgrade all outdated packages and applications
brew upgrade
brew upgrade --cask

# Clean up old versions and stale lock files
brew cleanup

echo "--- Finished Homebrew Update: $(date) ---"