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Memcached::getServerByKey

(PECL memcached >= 0.1.0)

Memcached::getServerByKeyDirige une clé sur un serveur

Description

public Memcached::getServerByKey(string $server_key): array|false

Memcached::getServerByKey() retourne le serveur qui devrait être sélectionné par une clé server_key dans les opérations de type Memcached::*ByKey().

Liste de paramètres

server_key

La clé d'identification du serveur.

Valeurs de retour

Retourne un tableau contenant 3 clés : host, port, et weight en cas de succès ou false si une erreur survient. Utilisez Memcached::getResultCode() si nécessaire.

Exemples

Exemple #1 Exemple avec Memcached::getServerByKey()

<?php
$m
= new Memcached();
$m->addServers(array(
array(
'mem1.domain.com', 11211, 40),
array(
'mem2.domain.com', 11211, 40),
array(
'mem3.domain.com', 11211, 20),
));

$m->setOption(Memcached::OPT_LIBKETAMA_COMPATIBLE, true);

var_dump($m->getServerByKey('user'));
var_dump($m->getServerByKey('log'));
var_dump($m->getServerByKey('ip'));
?>

Résultat de l'exemple ci-dessus est similaire à :

array(3) {
  ["host"]=>
  string(15) "mem3.domain.com"
  ["port"]=>
  int(11211)
  ["weight"]=>
  int(20)
}
array(3) {
  ["host"]=>
  string(15) "mem2.domain.com"
  ["port"]=>
  int(11211)
  ["weight"]=>
  int(40)
}
array(3) {
  ["host"]=>
  string(15) "mem2.domain.com"
  ["port"]=>
  int(11211)
  ["weight"]=>
  int(40)
}

add a note

User Contributed Notes 2 notes

up
5
zhaoyong dot lc at gmail dot com
11 years ago
The parameter server_key is very confusing, it's not a server key for MemCached Server, but it's key,in key-value pair which you stored in server.

<?php
$m
= new Memcached;
$m->addServers(array(
array(
'127.0.0.1',11212),
array(
'127.0.0.1',11211)
));
for(
$i=0;$i<10;$i++){
$key = 'key_'.$i;
$m->add($key, 1);
}
for(
$i=0;$i<10;$i++) {
$key = 'key_'.$i;
$arr = $m->getServerByKey($key);
echo (
$key.":\t".$arr['port']."\n");
}
?>

key_0: 11212
key_1: 11211
key_2: 11212
key_3: 11212
key_4: 11212
key_5: 11211
key_6: 11211
key_7: 11212
key_8: 11212
key_9: 11211
up
1
morphles
8 years ago
Just to clarify (as documentation of memcached, even for C lib, frankly is quite lacking), $server_key is hashed using same method as regular keys for values (I checked C source, as again docs......). So you should be able to see where set($key, $value) goes by using getServerByKey($key) with same key. This can be useful if one does not wish to bother with using/has no need to use *ByKey functions, but still want to know which servers are/should be used with regular keys, for implementing fallback or failure reporting.
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