feat(01-01): add environment check script (check-env.sh)

- Verifies Docker Engine >= 24.0, Compose V2, network utilities
- Reports system resources (RAM, CPU cores) with warnings if low
- Color-coded output (green pass, red fail, yellow warn)
- Exit code 0 on all checks pass, 1 on failures
- Idempotent - can be run multiple times safely

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

scripts/check-env.sh

@@ -0,0 +1,165 @@
+#!/bin/bash
+# Laboratori Cloud - Environment Check Script
+# Part of: "Corso Soluzioni Cloud"
+#
+# Description: Verifies Docker Engine >= 24.0, Compose V2, network utilities, and system resources
+# Usage: ./scripts/check-env.sh
+
+# Exit on error, but handle command failures gracefully
+
+# Color codes for output
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m' # No Color
+
+# Counters for summary
+PASS_COUNT=0
+FAIL_COUNT=0
+
+# Function to print pass message
+print_pass() {
+    echo -e "${GREEN}[PASS]${NC} $1"
+    ((PASS_COUNT++))
+}
+
+# Function to print fail message
+print_fail() {
+    echo -e "${RED}[FAIL]${NC} $1"
+    ((FAIL_COUNT++))
+}
+
+# Function to print warn message
+print_warn() {
+    echo -e "${YELLOW}[WARN]${NC} $1"
+}
+
+# Function to print info message
+print_info() {
+    echo "[INFO] $1"
+}
+
+echo "=========================================="
+echo "Laboratori Cloud - Environment Check"
+echo "=========================================="
+echo ""
+
+# 1. Docker Engine version check
+print_info "Checking Docker Engine version..."
+if command -v docker &> /dev/null; then
+    DOCKER_VERSION=$(docker --version | grep -oP '\d+\.\d+\.\d+' | head -1)
+    DOCKER_MAJOR=$(echo "$DOCKER_VERSION" | cut -d. -f1)
+
+    print_info "Found Docker Engine version: $DOCKER_VERSION"
+
+    if [ "$DOCKER_MAJOR" -ge 24 ]; then
+        print_pass "Docker Engine >= 24.0 (found $DOCKER_VERSION)"
+    else
+        print_fail "Docker Engine >= 24.0 required. Found: $DOCKER_VERSION"
+    fi
+else
+    print_fail "Docker Engine not found. Please install Docker >= 24.0"
+fi
+echo ""
+
+# 2. Docker Compose V2 check
+print_info "Checking Docker Compose V2..."
+if docker compose version &> /dev/null; then
+    COMPOSE_VERSION=$(docker compose version | grep -oP 'Docker Compose version v?\K[\d.]+' | head -1)
+    print_info "Found Docker Compose V2 version: $COMPOSE_VERSION"
+    print_pass "Docker Compose V2 is available (use 'docker compose' not 'docker-compose')"
+elif command -v docker-compose &> /dev/null; then
+    print_fail "Docker Compose V2 required. Found legacy 'docker-compose'. Please upgrade to Docker Compose V2"
+else
+    print_fail "Docker Compose V2 required. Use 'docker compose' not 'docker-compose'"
+fi
+echo ""
+
+# 3. Network utilities check
+print_info "Checking network utilities..."
+MISSING_UTILS=()
+
+# Check for netcat/nc
+if command -v nc &> /dev/null; then
+    print_pass "netcat (nc) is available"
+elif command -v netcat &> /dev/null; then
+    print_pass "netcat is available"
+else
+    MISSING_UTILS+=("netcat/nc")
+    print_fail "netcat (or nc) is required"
+fi
+
+# Check for curl
+if command -v curl &> /dev/null; then
+    print_pass "curl is available"
+else
+    MISSING_UTILS+=("curl")
+    print_fail "curl is required"
+fi
+
+# Check for ip (iproute2)
+if command -v ip &> /dev/null; then
+    print_pass "ip (iproute2) is available"
+else
+    MISSING_UTILS+=("ip (iproute2)")
+    print_fail "ip (iproute2) is required"
+fi
+
+if [ ${#MISSING_UTILS[@]} -gt 0 ]; then
+    print_fail "Missing network utilities: ${MISSING_UTILS[*]}"
+fi
+echo ""
+
+# 4. System resources check
+print_info "Checking system resources..."
+
+# Check RAM
+if [ -f /proc/meminfo ]; then
+    TOTAL_MEM_KB=$(grep MemTotal /proc/meminfo | awk '{print $2}')
+    TOTAL_MEM_GB=$((TOTAL_MEM_KB / 1024 / 1024))
+    print_info "Total RAM: ${TOTAL_MEM_GB}GB"
+
+    if [ "$TOTAL_MEM_GB" -ge 16 ]; then
+        print_pass "System has ${TOTAL_MEM_GB}GB RAM (recommended: 16GB)"
+    elif [ "$TOTAL_MEM_GB" -ge 8 ]; then
+        print_warn "System has ${TOTAL_MEM_GB}GB RAM (recommended: 16GB for all labs)"
+    else
+        print_fail "System has ${TOTAL_MEM_GB}GB RAM (minimum: 8GB, recommended: 16GB)"
+    fi
+elif command -v free &> /dev/null; then
+    TOTAL_MEM=$(free -h | awk '/^Mem:/ {print $2}')
+    print_info "Total RAM: $TOTAL_MEM"
+    print_warn "Could not determine exact RAM value. Please verify you have at least 8GB"
+else
+    print_warn "Could not determine system RAM. Please verify manually"
+fi
+
+# Check CPU cores
+if command -v nproc &> /dev/null; then
+    CPU_CORES=$(nproc)
+    print_info "CPU cores: $CPU_CORES"
+
+    if [ "$CPU_CORES" -ge 4 ]; then
+        print_pass "System has $CPU_CORES CPU cores"
+    else
+        print_warn "System has $CPU_CORES CPU cores (recommended: 4+ for best performance)"
+    fi
+else
+    print_warn "Could not determine CPU count"
+fi
+echo ""
+
+# Summary
+echo "=========================================="
+echo "Summary: $PASS_COUNT passed, $FAIL_COUNT failed"
+echo "=========================================="
+
+if [ "$FAIL_COUNT" -gt 0 ]; then
+    echo ""
+    print_fail "Environment check failed. Please fix the issues above before starting labs."
+    exit 1
+else
+    echo ""
+    print_pass "All environment checks passed! You're ready to start the labs."
+    exit 0
+fi