IO::Async::Resolver::StupidCache - a trivial caching layer around an
use IO::Async::Loop 0.62; use IO::Async::Resolver::StupidCache; my $loop = IO::Async::Loop->new; # Wrap the existing resolver in a cache $loop->set_resolver( IO::Async::Resolver::StupidCache->new( source => $loop->resolver ) ); # $loop->resolve requests will now be cached
This object class provides a wrapper around another IO::Async::Resolver instance, which applies a simple caching layer to avoid making identical lookups. This can be useful, for example, when performing a large number of HTTP requests to the same host or a small set of hosts, or other cases where it is expected that the same few resolver queries will be made over and over.
This is called a "stupid" cache because it is made without awareness of TTL values or other cache-relevant information that may be provided by DNS or other resolve methods. As such, it should not be relied upon to give always-accurate answers.
The following named parameters may be passed to
- source => IO::Async::Resolver
Optional. The source of the cache data. If not supplied, a new
IO::Async::Resolverinstance will be constructed.
- ttl => INT
Optional. Time-to-live of cache entries in seconds. If not supplied a default of 5 minutes will apply.
- max_size => INT
Optional. Maximum number of entries to keep in the cache. Entries will be evicted at random over this limit. If not supplied a default of 1000 entries will apply.
The following methods documented with a trailing call to
->get return Future instances.
Returns the source resolver
These methods perform identically to the base
IO::Async::Resolver class, except that the results are cached.
Futures are created with the
without_cancel method, so that multiple concurrent waiters are shielded from cancellation by one another.
Paul Evans <email@example.com>