Type for resolver configuration. Use defaultResolvConf to create a new value.

An example to use Google's public DNS cache instead of resolv.conf:

>>> let conf = defaultResolvConf { resolvInfo = RCHostName "8.8.8.8" }

An example to use multiple Google's public DNS cache concurrently:

>>> let conf = defaultResolvConf { resolvInfo = RCHostNames ["8.8.8.8","8.8.4.4"], resolvConcurrent = True }

An example to disable EDNS0:

>>> let conf = defaultResolvConf { resolvEDNS = [] }

An example to enable EDNS0 with a 1,280-bytes buffer:

>>> let conf = defaultResolvConf { resolvEDNS = [fromEDNS0 defaultEDNS0 { udpSize = 1280 }] }

An example to enable cache:

>>> let conf = defaultResolvConf { resolvCache = Just defaultCacheConf }

Return a default ResolvConf :

• resolvInfo is RCFilePath "/etc/resolv.conf".
• resolvTimeout is 3,000,000 micro seconds.
• resolvRetry is 3.
• resolvEDNS is EDNS0 with a 4,096-bytes buffer.
• resolvConcurrent is False.
• resolvCache is Nothing.

Server information.

Timeout in micro seconds.

The number of retries including the first try.

Additional resource records to specify EDNS.

Concurrent queries if multiple DNS servers are specified.

Cache configuration.

The type to specify a cache server.

Cache configuration for responses.

Default cache configuration.

>>> defaultCacheConf
CacheConf {maximumTTL = 300, pruningDelay = 10}

If RR's TTL is higher than this value, this value is used instead.

Cache pruning interval in seconds.

Intermediate abstract data type for resolvers. IP address information of DNS servers is generated according to resolvInfo internally. This value can be safely reused for withResolver .

The naming is confusing for historical reasons.

Make a ResolvSeed from a ResolvConf .

Examples:

>>> rs <- makeResolvSeed defaultResolvConf

Abstract data type of DNS Resolver. This includes newly seeded identifier generators for all specified DNS servers and a cache database.

Giving a thread-safe Resolver to the function of the second argument.

Giving thread-safe Resolver s to the function of the second argument. For each Resolver , multiple lookups must be done sequentially. Resolver s can be used concurrently.