Struct DnsSeeds 

pub struct DnsSeeds { /* private fields */ }

Seed discovery via DNS, the SeedDiscovery for clusters whose nodes are named by DNS records instead of configured addresses.

Implementations

impl DnsSeeds

pub fn new(query: Query) -> Result<Self, DnsSeedsError>

Discovery via the given Query, which a config file can provide. Resolves with the system resolver configuration; see with_resolver.

Errors

Fails if the system resolver configuration cannot be read.

pub fn srv(name: impl Into<String>) -> Result<Self, DnsSeedsError>

Discovery via the SRV records at the given name, e.g. _tellus._udp.svc.cluster.example: every record contributes its port paired with each address its target resolves to, so nodes can advertise differing ports. Resolves with the system resolver configuration; see with_resolver.

Errors

Fails if the system resolver configuration cannot be read.

pub fn ip( name: impl Into<String>, port: NonZeroU16, ) -> Result<Self, DnsSeedsError>

Discovery via the A/AAAA records at the given name, every address paired with the given port: for clusters whose nodes all advertise one well known port. Resolves with the system resolver configuration; see with_resolver.

Errors

Fails if the system resolver configuration cannot be read.

pub fn with_resolver(self, resolver: TokioResolver) -> Self

Replace the resolver DnsSeeds::new builds, e.g. by one pointed at specific name servers. That resolver keeps no response cache. A resolver which does returns the same addresses until its cached answer expires, so bootstrap sees nodes come and go only that late.

Trait Implementations

impl Debug for DnsSeeds

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

Formats the value using the given formatter.

impl SeedDiscovery for DnsSeeds

type Error = DnsSeedsError

The type of the discovery’s failures.

async fn resolve(&mut self) -> Result<Vec<SocketAddr>, DnsSeedsError>

Resolve the current seed addresses, this node’s own included when it is discoverable; order and duplicates are irrelevant. Called repeatedly by bootstrap, so a failure is retried, not fatal.