function cache_get

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7 cache.inc cache_get($cid, $bin = 'cache')
4.6 bootstrap.inc cache_get($key)
4.7 bootstrap.inc cache_get($key)
5 cache.inc cache_get($key, $table = 'cache')
6 cache.inc cache_get($cid, $table = 'cache')
6 cache-install.inc cache_get($key, $table = 'cache')

Returns data from the persistent cache.

Data may be stored as either plain text or as serialized data. cache_get will automatically return unserialized objects and arrays.

Parameters

$cid: The cache ID of the data to retrieve.

$bin: The cache bin to store the data in. Valid core values are 'cache_block', 'cache_bootstrap', 'cache_field', 'cache_filter', 'cache_form', 'cache_menu', 'cache_page', 'cache_path', 'cache_update' or 'cache' for the default cache.

Return value

The cache or FALSE on failure.

See also

cache_set()

50 calls to cache_get()
archiver_get_info in includes/common.inc
Retrieves a list of all available archivers.
book_menu_subtree_data in modules/book/book.module
Gets the data representing a subtree of the book hierarchy.
CacheClearCase::testMinimumCacheLifetime in modules/simpletest/tests/cache.test
Test minimum cache lifetime.
CacheSavingCase::checkVariable in modules/simpletest/tests/cache.test
Check or a variable is stored and restored properly.
CacheSavingCase::testNoEmptyCids in modules/simpletest/tests/cache.test
Test no empty cids are written in cache table.

... See full list

File

includes/cache.inc, line 55
Functions and interfaces for cache handling.

Code

function cache_get($cid, $bin = 'cache') {
  return _cache_get_object($bin)->get($cid);
}

Comments

The return value is an object representing the row in the cache table. To get the actual value out, access the data property. The data property is already unserialized.

Example:

<?php
cache_set
($cid, $myObject);
// ...
$cache = cache_get($cid);
$myObject = $cache->data;
?>

Note that $cid is a string. The convention seems to be to use colons to create a sort of namespacing. So your module may want to do something like $cid = 'mymodule:mything:50';

This function will return expired items in Drupal 7, here is the core issue for fixing in D8:

http://drupal.org/node/534092

This is not obvious from these API docs which is why I'm adding this note here.

To me it looks like they just completely removed it for D8 and kept the cache only for backward compatibility. Did this get moved/rewritten to somewhere else in D8 or was it just removed?

Here's an equivalent line in D7 and D8 (dev):

In D7 (taken from menu.module):

<?php
$cache
= cache_get($cid, 'cache_menu');
?>

And in D8, which uses cache():

<?php
$cache
= cache('menu')->get($cid);
?>

Cheers,

Albert.

Quick fix for this in D7 is to just check time() < $cache->expire before using $cache->data.