NAME
`IO::Async::Resolver::StupidCache' - a trivial caching layer around an
`IO::Async::Resolver'
SYNOPSIS
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
DESCRIPTION
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.
PARAMETERS
The following named parameters may be passed to `new' or `configure':
source => IO::Async::Resolver
Optional. The source of the cache data. If not supplied, a new
`IO::Async::Resolver' instance 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.
METHODS
$resolver = $cache->source
Returns the source resolver
$cache->resolve( %args ) ==> ( @result )
$cache->getaddrinfo( %args ) ==> ( @addrs )
$cache->getnameinfo( %args ) ==> ( $host, $service )
These methods perform identically to the base `IO::Async::Resolver'
class, except that the results are cached.
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>