Struct TtlConfig

pub struct TtlConfig { /* private fields */ }

The time-to-live (TTL) configuration used by the cache.

Minimum and maximum TTLs can be set for both positive responses and negative responses. Separate limits may be set depending on the query type.

Note that TTLs in DNS are represented as a number of seconds stored in a 32-bit unsigned integer. We use Duration here, instead of u32, which can express larger values than the DNS standard. Generally, a Duration greater than u32::MAX_VALUE shouldn’t cause any issue, as this will never be used in serialization, but note that this would be outside the standard range.

Implementations

impl TtlConfig

pub fn from_opts(opts: &ResolverOpts) -> TtlConfig

Construct the LRU’s TTL configuration based on the ResolverOpts configuration.

pub fn new( positive_min_ttl: Option<Duration>, negative_min_ttl: Option<Duration>, positive_max_ttl: Option<Duration>, negative_max_ttl: Option<Duration>, ) -> TtlConfig

Creates a new cache TTL configuration.

The provided minimum and maximum TTLs will be applied to all queries unless otherwise specified via Self::with_query_type_ttl_bounds.

If a minimum value is not provided, it will default to 0 seconds. If a maximum value is not provided, it will default to one day.

pub fn with_query_type_ttl_bounds( &mut self, query_type: RecordType, positive_min_ttl: Option<Duration>, negative_min_ttl: Option<Duration>, positive_max_ttl: Option<Duration>, negative_max_ttl: Option<Duration>, ) -> &mut TtlConfig

Override the minimum and maximum TTL values for a specific query type.

If a minimum value is not provided, it will default to 0 seconds. If a maximum value is not provided, it will default to one day.

pub fn positive_response_ttl_bounds( &self, query_type: RecordType, ) -> RangeInclusive<Duration>

Retrieves the minimum and maximum TTL values for positive responses.

pub fn negative_response_ttl_bounds( &self, query_type: RecordType, ) -> RangeInclusive<Duration>

Retrieves the minimum and maximum TTL values for negative responses.

Trait Implementations

impl Clone for TtlConfig

fn clone(&self) -> TtlConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TtlConfig

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

Formats the value using the given formatter.

impl Default for TtlConfig

fn default() -> TtlConfig

Returns the “default value” for a type.

impl PartialEq for TtlConfig

fn eq(&self, other: &TtlConfig) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for TtlConfig

impl StructuralPartialEq for TtlConfig