Validate Presence of Essential CLI Tools in Bash

#!/bin/bash

REQUIRED_COMMANDS=("node" "npm" "git" "docker")

for cmd in "${REQUIRED_COMMANDS[@]}"; do
  if ! command -v "$cmd" &> /dev/null; then
    echo "Error: Required command '$cmd' is not installed. Please install it to proceed."
    exit 1
  fi
done

echo "All required commands are installed. Proceeding..."

How it works: This script iterates through a predefined list of `REQUIRED_COMMANDS`. For each command, it uses `command -v "$cmd" &> /dev/null` to check if the executable is available in the system's PATH. If any required command is missing, an informative error message is printed to stderr, and the script exits immediately with a non-zero status, preventing further execution with incomplete dependencies.