Check FoundryVTT public DNS and create a markdown table of the results

check-foundry-dns.sh

#!/bin/bash

# Initial list of domains
DOMAINS=("api.foundryvtt.com" 
        "foundryvtt.com"
        "foundryvtt.s3.amazonaws.com" 
        "foundryvtt.s3.dualstack.us-west-2.amazonaws.com")

# Print the table header
echo "| Name | \`A\` | \`AAAA\` | Notes |"
echo "|------|:-:|:-----:|-------|"

# Set to keep track of checked domains
checked_domains=()

index=0
while [ $index -lt ${#DOMAINS[@]} ]; do
    domain=${DOMAINS[$index]}

    # Skip if we've already checked this domain
    if [[ " ${checked_domains[@]} " =~ " ${domain} " ]]; then
        ((index++))
        continue
    fi

    # Query A, AAAA, and CNAME records
    a_record=$(dig +short $domain A)
    aaaa_record=$(dig +short $domain AAAA)
    cname_record=$(dig +short $domain CNAME)

    # Check the records and set the appropriate symbols
    a_status="❌"
    aaaa_status="❌"
    notes=""

    if [[ ! -z $a_record ]]; then
        a_status="✅"
    fi

    # Check if the AAAA record is actually an IPv6 address
    if [[ $aaaa_record == *":"* ]]; then
        aaaa_status="✅"
    fi

    if [[ ! -z $cname_record ]]; then
        notes="\`CNAME\` to $cname_record"
        # Insert CNAME into the list of domains to check right after the current domain
        DOMAINS=("${DOMAINS[@]:0:$index+1}" "$cname_record" "${DOMAINS[@]:$index+1}")
    fi

    # Print the results in markdown table format
    echo "| $domain | $a_status | $aaaa_status | $notes |"

    # Mark the domain as checked
    checked_domains+=("$domain")

    ((index++))
done