DNS

The DNS module provides functions for performing DNS lookups.

dynamic_loader("nauthilus_dns")
local nauthilus_dns = require("nauthilus_dns")

nauthilus_dns.resolve

Performs a DNS record lookup for the specified domain and record type.

Syntax

local result, error = nauthilus_dns.resolve(domain, record_type)

Parameters

• domain (string): The domain name to look up
• record_type (string, optional): The type of DNS record to look up. Defaults to "A" if not specified. Supported values:
  • A: IPv4 address records
  • AAAA: IPv6 address records
  • MX: Mail exchange records
  • NS: Name server records
  • TXT: Text records
  • CNAME: Canonical name records
  • PTR: Pointer records (reverse DNS)

Returns

• result (table/string): The lookup result, which varies based on the record type:
  • For A, AAAA, NS, TXT, and PTR: A table of strings
  • For MX: A table of objects with host and pref (preference) fields
  • For CNAME: A string containing the canonical name
• error (string): An error message if the lookup fails

Example

dynamic_loader("nauthilus_dns")
local nauthilus_dns = require("nauthilus_dns")

-- Look up A records
local a_records, err = nauthilus_dns.resolve("example.com", "A")
if err then
  print("Error:", err)
else
  for i, ip in ipairs(a_records) do
    print("IP address:", ip)
  end
end

-- Look up MX records
local mx_records, err = nauthilus_dns.resolve("example.com", "MX")
if err then
  print("Error:", err)
else
  for i, mx in ipairs(mx_records) do
    print("Mail server:", mx.host, "Preference:", mx.pref)
  end
end

-- Look up CNAME record
local cname, err = nauthilus_dns.resolve("www.example.com", "CNAME")
if err then
  print("Error:", err)
else
  print("Canonical name:", cname)
end

warning

DNS lookups are blocking operations and may time out based on the server's DNS timeout configuration.