Struct DnsResolver 

pub struct DnsResolver { /* private fields */ }

DNS resolver for querying various record types.

Uses Google DNS (8.8.8.8) by default, but supports custom nameservers. The default resolver is cached and reused across queries to avoid repeated initialization overhead.

Implementations

impl DnsResolver

pub fn new() -> Self

Creates a new DNS resolver with default settings.

pub fn with_timeout(self, timeout: Duration) -> Self

Sets the timeout for DNS queries.

The default is 5 seconds, which is sufficient for most DNS queries.

pub async fn resolve( &self, domain: &str, record_type: RecordType, nameserver: Option<&str>, ) -> Result<Vec<DnsRecord>>

Resolves DNS records for a domain.

Arguments

• domain - The domain name to query
• record_type - The type of DNS record to look up (A, AAAA, MX, etc.)
• nameserver - Optional custom nameserver IP; uses Google DNS if None

pub async fn resolve_srv( &self, service: &str, protocol: &str, domain: &str, nameserver: Option<&str>, ) -> Result<Vec<DnsRecord>>

Resolves SRV records for a service.

Arguments

• service - The service name (e.g., “http”, “ldap”)
• protocol - The protocol (e.g., “tcp”, “udp”)
• domain - The domain name
• nameserver - Optional custom nameserver IP

impl DnsResolver

pub async fn presence(&self, domain: &str) -> DnsPresence

Probes whether a domain has any DNS presence by querying its apex NS records. A registered, delegated domain returns NS records; an unregistered domain returns NXDOMAIN (an empty record set).

This is a heuristic, not proof: a registered-but-undelegated domain also has no NS records, so callers should treat DnsPresence::Absent as “likely available” (medium confidence).

Trait Implementations

impl Clone for DnsResolver

fn clone(&self) -> DnsResolver

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DnsResolver

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for DnsResolver

fn default() -> Self

Returns the “default value” for a type.