Custom Commands Library

This guide provides instructions for creating and managing a custom commands library to streamline VPS administration tasks using Bash and Zsh.

Overview

A custom commands library allows you to:

• Consolidate frequently used commands
• Automate repetitive tasks
• Improve efficiency and consistency
• Standardize system operations

1. Creating the Custom Commands Script

a. Create Script File

Create a new file for your custom commands:

# Example: create command script in /usr/local/bin
sudo nano /data/nc_commands.sh

b. Add Shebang Line

Specify the interpreter at the beginning of the script:

#!/bin/bash

c. Define Custom Functions

Add your custom commands as functions within the script. Example:

#!/bin/bash

# Edit this script
edit_custom_commands() {
    sudo nano /usr/local/bin/custom_commands.sh
}

# Edit Zsh configuration
edit_zsh_config() {
    nano ~/.zshrc
}

# Refresh Zsh configuration
refresh_zsh() {
    source ~/.zshrc
}

# Docker utilities
docker_list_containers() {
	docker ps --format "table {{.Names}}\t{{.Status}}\t{{.Ports}}"
}

docker_inspect_network() {
    # Example: inspect Coolify network
    docker network inspect coolify
}

docker_view_logs() {
    # Example: view Nginx Proxy Manager logs
    docker container logs nginx-proxy-manager
}

d. Make Script Executable

Set execute permissions for the script:

sudo chmod +x /usr/local/bin/custom_commands.sh

2. Integrating with Zsh

a. Edit Zsh Configuration

Open your .zshrc file for editing:

# Ensure Zsh is your current shell
# zsh

# Edit Zsh configuration
nano ~/.zshrc

b. Source Custom Commands Script

Add the following lines to your .zshrc to load the custom commands:

# Source custom commands script
if [ -f /usr/local/bin/custom_commands.sh ]; then
    source /usr/local/bin/custom_commands.sh
else
    echo "Warning: /usr/local/bin/custom_commands.sh not found. Custom commands not loaded."
fi

c. Apply Changes

Reload your Zsh configuration to activate the changes:

source ~/.zshrc

Best Practices

1. Organization

   • Group related commands into functions
   • Use clear and descriptive function names
   • Add comments to explain complex commands

2. Security

   • Store scripts in a secure location (e.g., /usr/local/bin)
   • Limit execute permissions appropriately
   • Avoid hardcoding sensitive information

3. Maintenance

   • Regularly review and update commands
   • Test changes thoroughly
   • Document new commands and their usage

Example Commands

System Information

# Display system uptime
system_uptime() {
    uptime -p
}

# Show disk usage
disk_space() {
    df -h
}

# List open ports
open_ports() {
    sudo ss -tulnp
}

Service Management

# Restart a service (e.g., Nginx)
restart_service() {
    sudo systemctl restart nginx
}

# Check service status
service_status() {
    sudo systemctl status "$1" # Pass service name as argument
}

Backup and Restore

# Example: Perform a system backup
backup_system() {
    # Add backup script commands here
    echo "System backup initiated..."
}

Troubleshooting

1. Command Not Found

   • Ensure the script is sourced in .zshrc
   • Verify the script path is correct
   • Check execute permissions

2. Permission Issues

   • Use sudo for commands requiring root privileges
   • Check file ownership and permissions

3. Script Errors

   • Test functions individually
   • Use set -x in scripts for debugging
   • Review syntax and command validity

Maintenance Tasks

1. Regular Updates

   • Keep custom commands up-to-date
   • Add new useful commands as needed
   • Remove outdated or unused commands

2. Documentation

   • Maintain clear documentation for each command
   • Update help text or comments
   • Share command library with relevant team members

3. Version Control

   • Consider using Git for versioning your custom scripts
   • Track changes and manage revisions
   • Facilitate collaboration and backups

By maintaining a well-organized custom commands library, you can significantly enhance your productivity and ensure consistent system administration practices on your VPS.

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