README

MemcachedTags v1.0.5 for PHP >= 5.5

About

MemcachedTags for PHP is a mechanism for adding tags to keys in Memcached. It is very useful, if you need to select or delete some keys by tags. And tags are really useful for group invalidation.

Main features

• Data modification functions such as delete/add/set use Locks to prevent losing data.
• MemcachedTags does not affect original keys. It creates own keys for service tags.

How it works

I will try to explain a mechanism, how memcached stores tags.

Imagine, you have some 3 keys in memcached (user1, user2, user3):

MEMCACHED (key : value)
user1 : {"name":"Alexander", "sex":"m", "city":"London"}
user2 : {"name":"Irina", "sex":"f", "city":"London"}
user3 : {"name":"Dima", "sex":"m", "city":"Murmansk"}

Now, lets add tag 'London' to users:

// php code
MemcachedTags->addTagsToKeys('London', ['user1', 'user2']);

And, as result, the memcached will contain:

MEMCACHED (key : value)
user1 : {"name":"Alexander", "sex":"m", "city":"London"}
user2 : {"name":"Irina", "sex":"f", "city":"London"}
user3 : {"name":"Dima", "sex":"m", "city":"Murmansk"}

tag_k_user1 : London
tag_k_user2 : London

tag_t_London : user1||user2

And, lets add tags 'male' and 'female' to users:

// php code
MemcachedTags->addTagsToKeys('male', ['user1', 'user3']);
MemcachedTags->addTagsToKeys('female', 'user2');

And, as result, the memcached will contain:

MEMCACHED (key : value)
user1 : {"name":"Alexander", "sex":"m", "city":"London"}
user2 : {"name":"Irina", "sex":"f", "city":"London"}
user3 : {"name":"Dima", "sex":"m", "city":"Murmansk"}

tag_k_user1 : London||male
tag_k_user2 : London||female
tag_k_user3 : male

tag_t_London : user1||user2
tag_t_male   : user1||user3
tag_t_female : user2

Usage

<?php
require ('./vendor/autoload.php');
use MemcachedTags\MemcachedTags;

// Example 1. Create new Instance

$Memcached = new \Memcached();
$Memcached->addServer('127.0.0.1', '11211');

$MemcachedTags = new MemcachedTags($Memcached);

// Example 2. Adding some tags to key

// some test data
$Memcached->set('user:1', '{"name": "Alexander", "sex": "m", "country": "UK",     "city": "London"}');
$Memcached->set('user:2', '{"name": "Irina",     "sex": "f", "country": "UK",     "city": "London"}');
$Memcached->set('user:3', '{"name": "Ilya",      "sex": "m", "country": "Russia", "city": "Petersburg"}');
$Memcached->set('user:4', '{"name": "Dima",      "sex": "m", "country": "Russia", "city": "Murmansk"}');
$Memcached->set('user:5', '{"name": "Dom",       "sex": "m", "country": "UK",     "city": "London"}');

// Add tags to keys

$MemcachedTags->addTagsToKeys(['city:London', 'country:UK'], ['user:1', 'user:2', 'user:5']);
$MemcachedTags->addTagsToKeys(['city:Murmansk', 'country:Russia'], 'user:4');
$MemcachedTags->addTagsToKeys(['city:Petersburg', 'country:Russia'], 'user:3');

$MemcachedTags->addTagsToKeys('sex:m', ['user:1', 'user:3', 'user:4', 'user:5']);
$MemcachedTags->addTagsToKeys('sex:f', 'user:2');

$MemcachedTags->addTagsToKeys('all', ['user:1','user:2', 'user:3', 'user:4', 'user:5']);

// or you can create key with tags

$MemcachedTags->setKeyWithTags('user:1', 'Alexander', ['country:UK', 'city:London', 'sex:m', 'all']);

// Example 3. Get keys by tags

// Get users with tag <all>
var_dump(
    $MemcachedTags->getKeysByTag('all')
);
//    array(2) {
//      [0]=> string(6) "user:1"
//      [1]=> string(6) "user:2"
//      [2]=> string(6) "user:3"
//      [3]=> string(6) "user:4"
//      [4]=> string(6) "user:5"
//    }

// Get users with tag <country:UK>
var_dump(
    $MemcachedTags->getKeysByTag('country:UK')
);
//    array(2) {
//      [0]=> string(6) "user:1"
//      [1]=> string(6) "user:2"
//      [2]=> string(6) "user:5"
//    }

// Get users with tag <city:Petersburg> OR <city:Murmansk>
var_dump(
    $MemcachedTags->getKeysByTags(['city:Petersburg', 'city:Murmansk'], MemcachedTags::COMPILATION_OR)
);
//    array(2) {
//      [0]=> string(6) "user:3"
//      [1]=> string(6) "user:4"
//    }

// Get users with tags <country:UK> AND <sex:m>
var_dump(
    $MemcachedTags->getKeysByTags(['country:UK', 'sex:m'], MemcachedTags::COMPILATION_AND)
);
//    array(3) {
//      [0]=> string(6) "user:1"
//      [1]=> string(6) "user:5"
//    }

// Get users with tag <country:UK> AND WITHOUT <sex:m>
var_dump(
    $MemcachedTags->getKeysByTags(['country:UK', 'sex:m'], MemcachedTags::COMPILATION_XOR)
);
//    array(3) {
//      [0]=> string(6) "user:2"
//    }

// Example 4. Delete keys by tags

// Delete keys with tag <city:Murmansk>
var_dump(
    $MemcachedTags->deleteKeysByTag('city:Murmansk')
);
// int(1) - Count of deleted keys

// Delete keys with tag <city:London> WITHOUT <sex:f>
var_dump(
    $MemcachedTags->deleteKeysByTags(['city:London', 'sex:f'], MemcachedTags::COMPILATION_XOR)
);
// int(2) - Count of deleted keys

Methods

MemcachedTags :: __construct ( \Memcached $Memcached , array $config = null )

Create a new instance of MemcachedTags.

Method Parameters

1. \Memcached $Memcached - Instance of Memcached
2. array $config, default = null
   • prefix - is a prefix for service keys in Memcached storage, like namespace.
   • separator - special char(s) that , by default ||. It is service parameter for the gluing of tags to the Memcached. This value should not use in the name tags or keys.

Example

$Lock = new MemcachedTags($Memcached);
// or
$Lock = new MemcachedTags($Memcached, [
    'prefix' => 'myTag',
    'separator' => '<;>',
]);

bool MemcachedTags :: addTagsToKeys ( string|string[] $tags , string|string[] $keys )

Adds each key specified tags. Returns true on success or false on failure.

Method Parameters

1. string|string[] $tags - Tag or list of tags that will be added to each key.
2. string|string[] $keys - Existing keys in Memcached for tags

Example

$MemcachedTags->addTagsToKeys(['city:London', 'country:UK'], ['user:1', 'user:2', 'user:5']);
$MemcachedTags->addTagsToKeys(['city:Murmansk', 'country:Russia'], 'user:4');
$MemcachedTags->addTagsToKeys(['big', 'red'], 'apple');
$MemcachedTags->addTagsToKeys(['green', 'tasty'], 'orange');

int MemcachedTags :: deleteKey ( string $key )

Delete key and update dependent tags. Returns count of deleted keys (0 or 1).

Method Parameters

1. string $key - Name of key.

Example

$MemcachedTags->deleteKey('user:1');

int MemcachedTags :: deleteKeys ( string[] $keys )

Delete keys and update dependent tags. Returns count of deleted keys.

Method Parameters

1. string[] $keys - List of keys.

Example

$MemcachedTags->deleteKey(['user:1', 'user:2']);

int MemcachedTags :: deleteTag ( string $tag )

Delete tag. Keys will be not affected. Returns count of deleted tags. (0 or 1)

Method Parameters

1. string $tag - Name of tag.

Example

$MemcachedTags->deleteTag('big');

int MemcachedTags :: deleteTags ( string[] $tags )

Delete several tags. Keys will be not affected. Returns count of deleted tags.

Method Parameters

1. string[] $tags - List of tags

Example

$MemcachedTags->deleteTags(['big', 'tasty', 'old']);

int MemcachedTags :: deleteKeysByTag ( string $tag )

Delete keys by tag. Returns count of deleted keys.

Method Parameters

1. string tag - Name of tag.

Example

$MemcachedTags->deleteKeysByTag('city:London');
// or
$MemcachedTags->deleteKeysByTag('sql');

int MemcachedTags :: deleteKeysByTags ( string[] $tags [, int $compilation = MemcachedTags::COMPILATION_ALL] )

Delete keys by several tags. Returns count of deleted keys.

Method Parameters

1. string[] tags - List of tags
2. int $compilation, default = MemcachedTags::COMPILATION_ALL - The method of combining tags.
   • MemcachedTags::COMPILATION_ALL - The same as MemcachedTags::COMPILATION_OR.
   • MemcachedTags::COMPILATION_AND - Delete keys that have every tags.
   • MemcachedTags::COMPILATION_OR - Delete keys that have any tags.
   • MemcachedTags::COMPILATION_XOR - Delete keys containing tag1 that are not have any of the other tags.

Example

// Delete all apples and oranges
$MemcachedTags->deleteKeysByTags(['apple', 'oranges']);

// Delete only big oranges
$MemcachedTags->deleteKeysByTags(['big', 'oranges'], MemcachedTags::COMPILATION_AND);

// Delete all orange expect big oranges
$MemcachedTags->deleteKeysByTags(['oranges', 'big'], MemcachedTags::COMPILATION_XOR);

string[] MemcachedTags :: getKeysByTag ( string $tag )

Returns a list of keys with tag.

Method Parameters

1. string tag - Name of tag.

Example

$MemcachedTags->getKeysByTag('big');
// or
$MemcachedTags->getKeysByTag('red');

string[]|array MemcachedTags :: getKeysByTags ( string[] $tags [, int $compilation = MemcachedTags::COMPILATION_ALL] )

Returns a list of keys by several tags.

Method Parameters

1. string[] tags - List of tags.
2. int $compilation, default = MemcachedTags::COMPILATION_ALL - The method of combining tags.
   • MemcachedTags::COMPILATION_ALL - Returns array with keys for every tag. array(tag1 => [key1, key2], ...)
   • MemcachedTags::COMPILATION_AND - Returns a list of keys that have every tags.
   • MemcachedTags::COMPILATION_OR - Returns a list of keys that have any tags.
   • MemcachedTags::COMPILATION_XOR - Returns a list of keys containing tag1 that are not have any of the other tags.

Example

// Get all apples and oranges
$MemcachedTags->getKeysByTags(['apple', 'oranges']);

// Get all apples or oranges
$MemcachedTags->getKeysByTags(['apple', 'oranges'], MemcachedTags::COMPILATION_OR);

// Get only big oranges
$MemcachedTags->getKeysByTags(['big', 'oranges'], MemcachedTags::COMPILATION_AND);

// Get all orange expect big oranges
$MemcachedTags->getKeysByTags(['oranges', 'big'], MemcachedTags::COMPILATION_XOR);

string[] MemcachedTags :: getTagsByKey ( string $key )

Returns list of tags or empty list.

Method Parameters

1. string $key - Key in Memcached.

Example

$MemcachedTags->getTagsByKey('user:1');

bool MemcachedTags :: setKeyWithTags ( string $key , string $value , string|string[] $tags )

Set value and tags to key. Returns result as bool.

Method Parameters

1. string $key - The key under which to store the value.
2. string $value - The value to store.
3. string|string[] $tags - Tag or list of tags for the key.

Example

$MemcachedTags->setKeyWithTags('user:1', 'Alexander', ['sex:m', 'city:London']);

bool MemcachedTags :: setKeysWithTags ( array $items , string|string[] $tags )

Set values and tags to several keys. Returns result as bool.

Method Parameters

1. string $items - An array of key/value pairs to store on the server.
2. string|string[] $tags - Tag or list of tags for the items.

Example

$MemcachedTags->setKeysWithTags(['user:1' => 'Alexander', 'user:2' => 'Irina'], 'city:London');

Installation

Composer

Download composer:

wget -nc http://getcomposer.org/composer.phar

and add dependency to your project:

php composer.phar require cheprasov/php-memcached-tags

Running tests

To run tests type in console:

./vendor/bin/phpunit ./test/

Something doesn't work

Feel free to fork project, fix bugs and finally request for pull