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https://github.com/mons/anyevent-memcached

AnyEvent memcached client
https://github.com/mons/anyevent-memcached

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AnyEvent memcached client

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NAME
AnyEvent::Memcached - AnyEvent memcached client

SYNOPSIS
use AnyEvent::Memcached;

my $memd = AnyEvent::Memcached->new(
servers => [ "10.0.0.15:11211", "10.0.0.15:11212" ], # same as in Cache::Memcached
debug => 1,
compress_threshold => 10000,
namespace => 'my-namespace:',

# May use another hashing algo:
hasher => 'AnyEvent::Memcached::Hash::WithNext',

cv => $cv, # AnyEvent->condvar: group callback
);

$memd->set_servers([ "10.0.0.15:11211", "10.0.0.15:11212" ]);

# Basic methods are like in Cache::Memcached, but with additional cb => sub { ... };
# first argument to cb is return value, second is the error(s)

$memd->set( key => $value, cb => sub {
shift or warn "Set failed: @_"
} );

# Single get
$memd->get( 'key', cb => sub {
my ($value,$err) = shift;
$err and return warn "Get failed: @_";
warn "Value for key is $value";
} );

# Multi-get
$memd->get( [ 'key1', 'key2' ], cb => sub {
my ($values,$err) = shift;
$err and return warn "Get failed: @_";
warn "Value for key1 is $values->{key1} and value for key2 is $values->{key2}"
} );

# Additionally there is rget (see memcachedb-1.2.1-beta)

$memd->rget( 'fromkey', 'tokey', cb => sub {
my ($values,$err) = shift;
$err and warn "Get failed: @_";
while (my ($key,$value) = each %$values) {
# ...
}
} );

# Rget with sorted responce values
$memd->rget( 'fromkey', 'tokey', rv => 'array' cb => sub {
my ($values,$err) = shift;
$err and warn "Get failed: @_";
for (0 .. $#values/2) {
my ($key,$value) = @$values[$_*2,$_*2+1];
}
} );

DESCRIPTION
Asyncronous "memcached/memcachedb" client for AnyEvent framework

NOTICE
There is a notices in Cache::Memcached::AnyEvent related to this module.
They all has been fixed

Prerequisites
We no longer need Object::Event and Devel::Leak::Cb. At all, the
dependency list is like in Cache::Memcached + AnyEvent

Binary protocol
It seems to me, that usage of binary protocol from pure perl gives
very little advantage. So for now I don't implement it

Unimplemented Methods
There is a note, that get_multi is not implementeted. In fact, it
was implemented by method "get", but the documentation was wrong.

In general, this module follows the spirit of AnyEvent rather than
correspondence to Cache::Memcached interface.

METHODS
new %args
Currently supported options:

servers =item namespace =item debug =item cv =item compress_threshold
=item compress_enable =item timeout =item hasher
If set, will use instance of this class for hashing instead of
default. For implementing your own hashing, see sources of
AnyEvent::Memcached::Hash and AnyEvent::Memcached::Hash::With::Next

noreply
If true, additional connection will established for noreply
commands.

cas If true, will enable cas/gets commands (since they are not suppotred
in memcachedb)

set_servers
Setup server list

connect
Establish connection to all servers and invoke event C, when ready

set( $key, $value, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Unconditionally sets a key to a given value in the memcache.

$rc is

'1' Successfully stored

'0' Item was not stored

undef
Error happens, see $err

cas( $key, $cas, $value, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
$memd->gets($key, cb => sub {
my $value = shift;
unless (@_) { # No errors
my ($cas,$val) = @$value;
# Change your value in $val
$memd->cas( $key, $cas, $value, cb => sub {
my $rc = shift;
if ($rc) {
# stored
} else {
# ...
}
});
}
})

$rc is the same, as for "set"

Store the $value on the server under the $key, but only if CAS value
associated with this key is equal to $cas. See also "gets"

add( $key, $value, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Like "set", but only stores in memcache if the key doesn't already
exist.

replace( $key, $value, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Like "set", but only stores in memcache if the key already exists. The
opposite of add.

append( $key, $value, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Append the $value to the current value on the server under the $key.

append command first appeared in memcached 1.2.4.

prepend( $key, $value, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Prepend the $value to the current value on the server under the $key.

prepend command first appeared in memcached 1.2.4.

get( $key, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Retrieve the value for a $key. $key should be a scalar

get( $keys : ARRAYREF, [cv => $cv], [ expire => $expire ], cb => $cb->( $values_hash, $err ) )
Retrieve the values for a $keys. Return a hash with keys/values

gets( $key, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Retrieve the value and its CAS for a $key. $key should be a scalar.

$rc is a reference to an array [$cas, $value], or nothing for
non-existent key

gets( $keys : ARRAYREF, [cv => $cv], [ expire => $expire ], cb => $cb->( $rc, $err ) )
Retrieve the values and their CAS for a $keys.

$rc is a hash reference with $rc->{$key} is a reference to an array
[$cas, $value]

delete( $key, [cv => $cv], [ noreply => 1 ], cb => $cb->( $rc, $err ) )
Delete $key and its value from the cache.

If "noreply" is true, cb doesn't required

del
Alias for "delete"

remove
Alias for "delete"

incr( $key, $increment, [cv => $cv], [ noreply => 1 ], cb => $cb->( $rc, $err ) )
Increment the value for the $key by $delta. Starting with memcached
1.3.3 $key should be set to a number or the command will fail. Note that
the server doesn't check for overflow.

If "noreply" is true, cb doesn't required, and if passed, simply called
with rc = 1

Similar to DBI, zero is returned as "0E0", and evaluates to true in a
boolean context.

decr( $key, $decrement, [cv => $cv], [ noreply => 1 ], cb => $cb->( $rc, $err ) )
Opposite to "incr"

rget( $from, $till, [ max => 100 ], [ '+left' => 1 ], [ '+right' => 1 ], [cv => $cv], [ rv => 'array' ], cb => $cb->( $rc, $err ) )
Memcachedb 1.2.1-beta implements rget method, that allows to look
through the whole storage

$from
the starting key

$till
finishing key

+left
If true, then starting key will be included in results. true by
default

+right
If true, then finishing key will be included in results. true by
default

max Maximum number of results to fetch. 100 is the maximum and is the
default

rv If passed rv => 'array', then the return value will be arrayref with
values in order, returned by memcachedb.

incadd ( $key, $increment, [cv => $cv], [ noreply => 1 ], cb => $cb->( $rc, $err ) )
Increment key, and if it not exists, add it with initial value. If add
fails, try again to incr or fail

destroy
Shutdown object as much, as possible, incl cleaning of incapsulated
objects

BUGS
Feature requests are welcome

Bug reports are welcome

AUTHOR
Mons Anderson, ""

COPYRIGHT & LICENSE
Copyright 2009 Mons Anderson, all rights reserved.

This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.