MediaWiki REL1_31
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interface is intended to be more or less compatible with the PHP memcached client. More...
Public Member Functions | |
__construct (array $params=[]) | |
$params include: | |
add ( $key, $value, $exptime=0) | |
addBusyCallback (callable $workCallback) | |
Let a callback be run to avoid wasting time on special blocking calls. | |
changeTTL ( $key, $expiry=0) | |
Reset the TTL on a key if it exists. | |
clearLastError () | |
Clear the "last error" registry. | |
decr ( $key, $value=1) | |
Decrease stored value of $key by $value while preserving its TTL. | |
delete ( $key) | |
Delete an item. | |
deleteObjectsExpiringBefore ( $date, $progressCallback=false) | |
Delete all objects expiring before a certain date. | |
get ( $key, $flags=0, $oldFlags=null) | |
Get an item with the given key. | |
getLastError () | |
Get the "last error" registered; clearLastError() should be called manually. | |
getMulti (array $keys, $flags=0) | |
Get an associative array containing the item for each of the keys that have items. | |
getQoS ( $flag) | |
getScopedLock ( $key, $timeout=6, $expiry=30, $rclass='') | |
Get a lightweight exclusive self-unlocking lock. | |
getWithSetCallback ( $key, $ttl, $callback, $flags=0) | |
Get an item with the given key, regenerating and setting it if not found. | |
incr ( $key, $value=1) | |
Increase stored value of $key by $value while preserving its TTL. | |
incrWithInit ( $key, $ttl, $value=1, $init=1) | |
Increase stored value of $key by $value while preserving its TTL. | |
lock ( $key, $timeout=6, $expiry=6, $rclass='') | |
Acquire an advisory lock on a key string. | |
makeGlobalKey ( $class, $component=null) | |
Make a global cache key. | |
makeKey ( $class, $component=null) | |
Make a cache key, scoped to this instance's keyspace. | |
makeKeyInternal ( $keyspace, $args) | |
Construct a cache key. | |
merge ( $key, callable $callback, $exptime=0, $attempts=10, $flags=0) | |
Merge changes into the existing cache value (possibly creating a new one) | |
modifySimpleRelayEvent (array $event) | |
Modify a cache update operation array for EventRelayer::notify() | |
set ( $key, $value, $exptime=0, $flags=0) | |
Set an item. | |
setDebug ( $bool) | |
setLogger (LoggerInterface $logger) | |
setMockTime (&$time) | |
setMulti (array $data, $exptime=0) | |
Batch insertion. | |
unlock ( $key) | |
Release an advisory lock on a key string. | |
Public Attributes | |
const | ERR_NO_RESPONSE = 1 |
const | ERR_NONE = 0 |
Possible values for getLastError() | |
const | ERR_UNEXPECTED = 3 |
const | ERR_UNREACHABLE = 2 |
const | READ_LATEST = 1 |
Bitfield constants for get()/getMulti() | |
const | READ_VERIFIED = 2 |
const | WRITE_CACHE_ONLY = 2 |
const | WRITE_SYNC = 1 |
Bitfield constants for set()/merge() | |
Public Attributes inherited from IExpiringStore | |
const | ATTR_EMULATION = 1 |
const | ATTR_SYNCWRITES = 2 |
const | QOS_EMULATION_SQL = 1 |
const | QOS_SYNCWRITES_BE = 2 |
const | QOS_SYNCWRITES_NONE = 1 |
const | QOS_SYNCWRITES_QC = 3 |
const | QOS_SYNCWRITES_SS = 4 |
const | QOS_UNKNOWN = INF |
const | TTL_DAY = 86400 |
const | TTL_HOUR = 3600 |
const | TTL_INDEFINITE = 0 |
const | TTL_MINUTE = 60 |
const | TTL_MONTH = 2592000 |
const | TTL_PROC_LONG = 30 |
const | TTL_PROC_SHORT = 3 |
const | TTL_SECOND = 1 |
const | TTL_WEEK = 604800 |
const | TTL_YEAR = 31536000 |
Protected Member Functions | |
cas ( $casToken, $key, $value, $exptime=0) | |
Check and set an item. | |
convertExpiry ( $exptime) | |
Convert an optionally relative time to an absolute time. | |
convertToRelative ( $exptime) | |
Convert an optionally absolute expiry time to a relative time. | |
debug ( $text) | |
doGet ( $key, $flags=0) | |
getCurrentTime () | |
getWithToken ( $key, &$casToken, $flags=0) | |
isInteger ( $value) | |
Check if a value is an integer. | |
mergeFlagMaps (array $bags) | |
Merge the flag maps of one or more BagOStuff objects into a "lowest common denominator" map. | |
mergeViaCas ( $key, $callback, $exptime=0, $attempts=10) | |
mergeViaLock ( $key, $callback, $exptime=0, $attempts=10, $flags=0) | |
setLastError ( $err) | |
Set the "last error" registry. | |
Protected Attributes | |
callback null | $asyncHandler |
int[] | $attrMap = [] |
Map of (ATTR_* class constant => QOS_* class constant) | |
callable[] | $busyCallbacks = [] |
string | $keyspace = 'local' |
int | $lastError = self::ERR_NONE |
ERR_* class constant. | |
array[] | $locks = [] |
Lock tracking. | |
LoggerInterface | $logger |
int | $syncTimeout |
Seconds. | |
Private Member Functions | |
trackDuplicateKeys ( $key) | |
Track the number of times that a given key has been used. | |
Private Attributes | |
bool | $debugMode = false |
bool | $dupeTrackScheduled = false |
array | $duplicateKeyLookups = [] |
bool | $reportDupes = false |
float null | $wallClockOverride |
interface is intended to be more or less compatible with the PHP memcached client.
backends for local hash array and SQL table included:
Definition at line 47 of file BagOStuff.php.
BagOStuff::__construct | ( | array | $params = [] | ) |
$params include:
array | $params |
Reimplemented in MemcachedBagOStuff, APCBagOStuff, and APCUBagOStuff.
Definition at line 103 of file BagOStuff.php.
References $params, and setLogger().
BagOStuff::add | ( | $key, | |
$value, | |||
$exptime = 0 ) |
string | $key | |
mixed | $value | |
int | $exptime |
Reimplemented in EmptyBagOStuff, RedisBagOStuff, MemcachedBagOStuff, MemcachedPeclBagOStuff, MultiWriteBagOStuff, and ReplicatedBagOStuff.
Definition at line 546 of file BagOStuff.php.
References $value.
BagOStuff::addBusyCallback | ( | callable | $workCallback | ) |
Let a callback be run to avoid wasting time on special blocking calls.
The callbacks may or may not be called ever, in any particular order. They are likely to be invoked when something WRITE_SYNC is used used. They should follow a caching pattern as shown below, so that any code using the word will get it's result no matter what happens.
callable | $workCallback |
Definition at line 657 of file BagOStuff.php.
Referenced by Wikimedia\Rdbms\ChronologyProtector\shutdown().
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Check and set an item.
mixed | $casToken | |
string | $key | |
mixed | $value | |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
Exception |
Reimplemented in MemcachedBagOStuff, MemcachedPeclBagOStuff, and SqlBagOStuff.
Definition at line 336 of file BagOStuff.php.
Referenced by mergeViaCas().
BagOStuff::changeTTL | ( | $key, | |
$expiry = 0 ) |
Reset the TTL on a key if it exists.
string | $key | |
int | $expiry |
Reimplemented in MemcachedPeclBagOStuff, RedisBagOStuff, SqlBagOStuff, and MemcachedBagOStuff.
Definition at line 389 of file BagOStuff.php.
BagOStuff::clearLastError | ( | ) |
Clear the "last error" registry.
Reimplemented in CachedBagOStuff, MultiWriteBagOStuff, and ReplicatedBagOStuff.
Definition at line 624 of file BagOStuff.php.
Referenced by lock(), mergeViaCas(), and mergeViaLock().
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Convert an optionally relative time to an absolute time.
int | $exptime |
Definition at line 695 of file BagOStuff.php.
References getCurrentTime().
Referenced by SqlBagOStuff\cas(), HashBagOStuff\set(), and SqlBagOStuff\setMulti().
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Convert an optionally absolute expiry time to a relative time.
If an absolute time is specified which is in the past, use a short expiry time.
int | $exptime |
Definition at line 710 of file BagOStuff.php.
References getCurrentTime().
Referenced by RedisBagOStuff\add(), RedisBagOStuff\changeTTL(), RedisBagOStuff\set(), and RedisBagOStuff\setMulti().
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string | $text |
Definition at line 682 of file BagOStuff.php.
Referenced by RedisBagOStuff\getMulti(), SqlBagOStuff\getMulti(), RedisBagOStuff\logRequest(), and RedisBagOStuff\setMulti().
BagOStuff::decr | ( | $key, | |
$value = 1 ) |
Decrease stored value of $key by $value while preserving its TTL.
string | $key | |
int | $value |
Reimplemented in APCBagOStuff, APCUBagOStuff, MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, MultiWriteBagOStuff, and ReplicatedBagOStuff.
Definition at line 581 of file BagOStuff.php.
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abstract |
Delete an item.
string | $key |
Reimplemented in APCBagOStuff, APCUBagOStuff, EmptyBagOStuff, HashBagOStuff, MemcachedBagOStuff, MemcachedPeclBagOStuff, MultiWriteBagOStuff, RedisBagOStuff, ReplicatedBagOStuff, RESTBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.
BagOStuff::deleteObjectsExpiringBefore | ( | $date, | |
$progressCallback = false ) |
Delete all objects expiring before a certain date.
string | $date | The reference date in MW format |
callable | bool | $progressCallback | Optional, a function which will be called regularly during long-running operations with the percentage progress as the first parameter. |
Reimplemented in CachedBagOStuff, MultiWriteBagOStuff, and SqlBagOStuff.
Definition at line 501 of file BagOStuff.php.
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string | $key | |
int | $flags | Bitfield of BagOStuff::READ_* constants [optional] |
Reimplemented in APCBagOStuff, APCUBagOStuff, CachedBagOStuff, EmptyBagOStuff, HashBagOStuff, MemcachedBagOStuff, MultiWriteBagOStuff, RedisBagOStuff, ReplicatedBagOStuff, RESTBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.
Referenced by get().
BagOStuff::get | ( | $key, | |
$flags = 0, | |||
$oldFlags = null ) |
Get an item with the given key.
If the key includes a determistic input hash (e.g. the key can only have the correct value) or complete staleness checks are handled by the caller (e.g. nothing relies on the TTL), then the READ_VERIFIED flag should be set. This lets tiered backends know they can safely upgrade a cached value to higher tiers using standard TTLs.
string | $key | |
int | $flags | Bitfield of BagOStuff::READ_* constants [optional] |
int | $oldFlags | [unused] |
Definition at line 182 of file BagOStuff.php.
References doGet(), and trackDuplicateKeys().
Referenced by MediaWiki\Session\SessionBackend\__construct(), Title\newFromTextThrow(), Wikimedia\Rdbms\ChronologyProtector\shutdown(), and BagOStuffTest\testReportDupes().
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Definition at line 807 of file BagOStuff.php.
Referenced by convertExpiry(), convertToRelative(), HashBagOStuff\expire(), and getScopedLock().
BagOStuff::getLastError | ( | ) |
Get the "last error" registered; clearLastError() should be called manually.
Reimplemented in CachedBagOStuff, MultiWriteBagOStuff, and ReplicatedBagOStuff.
Definition at line 616 of file BagOStuff.php.
Referenced by lock(), mergeViaCas(), and mergeViaLock().
BagOStuff::getMulti | ( | array | $keys, |
$flags = 0 ) |
Get an associative array containing the item for each of the keys that have items.
array | $keys | List of strings |
int | $flags | Bitfield; supports READ_LATEST [optional] |
Reimplemented in MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, RedisBagOStuff, ReplicatedBagOStuff, and SqlBagOStuff.
Definition at line 512 of file BagOStuff.php.
BagOStuff::getQoS | ( | $flag | ) |
int | $flag | ATTR_* class constant |
Definition at line 778 of file BagOStuff.php.
Referenced by Wikimedia\Rdbms\ChronologyProtector\shutdown().
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Get a lightweight exclusive self-unlocking lock.
Note that the same lock cannot be acquired twice.
This is useful for task de-duplication or to avoid obtrusive (though non-corrupting) DB errors like INSERT key conflicts or deadlocks when using LOCK IN SHARE MODE.
string | $key | |
int | $timeout | Lock wait timeout; 0 for non-blocking [optional] |
int | $expiry | Lock expiry [optional]; 1 day maximum |
string | $rclass | Allow reentry if set and the current lock used this value |
Definition at line 472 of file BagOStuff.php.
References getCurrentTime(), lock(), and unlock().
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Get an item with the given key, regenerating and setting it if not found.
If the callback returns false, then nothing is stored.
string | $key | |
int | $ttl | Time-to-live (seconds) |
callable | $callback | Callback that derives the new value |
int | $flags | Bitfield of BagOStuff::READ_* constants [optional] |
Definition at line 152 of file BagOStuff.php.
References $value.
Referenced by ChangesList\numberofWatchingusers().
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string | $key | |
mixed | &$casToken | |
int | $flags | Bitfield of BagOStuff::READ_* constants [optional] |
Exception |
Reimplemented in MemcachedBagOStuff, MemcachedPeclBagOStuff, and SqlBagOStuff.
Definition at line 240 of file BagOStuff.php.
Referenced by mergeViaCas().
BagOStuff::incr | ( | $key, | |
$value = 1 ) |
Increase stored value of $key by $value while preserving its TTL.
string | $key | Key to increase |
int | $value | Value to add to $key (Default 1) |
Reimplemented in SqlBagOStuff, APCBagOStuff, APCUBagOStuff, MemcachedPeclBagOStuff, MemcachedPhpBagOStuff, MultiWriteBagOStuff, RedisBagOStuff, and ReplicatedBagOStuff.
Definition at line 559 of file BagOStuff.php.
References $value, isInteger(), lock(), and unlock().
Referenced by decr(), and incrWithInit().
BagOStuff::incrWithInit | ( | $key, | |
$ttl, | |||
$value = 1, | |||
$init = 1 ) |
Increase stored value of $key by $value while preserving its TTL.
This will create the key with value $init and TTL $ttl instead if not present
string | $key | |
int | $ttl | |
int | $value | |
int | $init |
Definition at line 597 of file BagOStuff.php.
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Check if a value is an integer.
mixed | $value |
Definition at line 728 of file BagOStuff.php.
References $value.
Referenced by APCBagOStuff\getUnserialize(), incr(), and APCBagOStuff\setSerialize().
BagOStuff::lock | ( | $key, | |
$timeout = 6, | |||
$expiry = 6, | |||
$rclass = '' ) |
Acquire an advisory lock on a key string.
Note that if reentry is enabled, duplicate calls ignore $expiry
string | $key | |
int | $timeout | Lock wait timeout; 0 for non-blocking [optional] |
int | $expiry | Lock expiry [optional]; 1 day maximum |
string | $rclass | Allow reentry if set and the current lock used this value |
Reimplemented in CachedBagOStuff, MultiWriteBagOStuff, and ReplicatedBagOStuff.
Definition at line 406 of file BagOStuff.php.
References add, clearLastError(), and getLastError().
Referenced by getScopedLock(), incr(), mergeViaLock(), and Wikimedia\Rdbms\ChronologyProtector\shutdown().
BagOStuff::makeGlobalKey | ( | $class, | |
$component = null ) |
Make a global cache key.
string | $class | Key class |
string | $component | [optional] Key component (starting with a key collection name) |
Reimplemented in CachedBagOStuff, and MultiWriteBagOStuff.
Definition at line 757 of file BagOStuff.php.
References makeKeyInternal().
Referenced by Wikimedia\Rdbms\ChronologyProtector\__construct(), Wikimedia\Rdbms\DatabaseMysqlBase\getMasterServerInfo(), Wikimedia\Rdbms\ChronologyProtector\getTouchedKey(), and BagOStuffTest\testMakeKey().
BagOStuff::makeKey | ( | $class, | |
$component = null ) |
Make a cache key, scoped to this instance's keyspace.
string | $class | Key class |
string | $component | [optional] Key component (starting with a key collection name) |
Reimplemented in CachedBagOStuff, and MultiWriteBagOStuff.
Definition at line 769 of file BagOStuff.php.
References makeKeyInternal().
Referenced by SiteStatsUpdate\getTypeCacheKey(), and BagOStuffTest\testMakeKey().
BagOStuff::makeKeyInternal | ( | $keyspace, | |
$args ) |
Construct a cache key.
string | $keyspace | |
array | $args |
Reimplemented in MemcachedBagOStuff.
Definition at line 740 of file BagOStuff.php.
References $args.
Referenced by makeGlobalKey(), makeKey(), and BagOStuffTest\testMakeKey().
BagOStuff::merge | ( | $key, | |
callable | $callback, | ||
$exptime = 0, | |||
$attempts = 10, | |||
$flags = 0 ) |
Merge changes into the existing cache value (possibly creating a new one)
The callback function returns the new value given the current value (which will be false if not present), and takes the arguments: (this BagOStuff, cache key, current value, TTL). The TTL parameter is reference set to $exptime. It can be overriden in the callback.
string | $key | |
callable | $callback | Callback method to be executed |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
int | $attempts | The amount of times to attempt a merge in case of failure |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
InvalidArgumentException |
Reimplemented in EmptyBagOStuff, MemcachedBagOStuff, ReplicatedBagOStuff, WinCacheBagOStuff, and SqlBagOStuff.
Definition at line 279 of file BagOStuff.php.
References mergeViaLock().
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Merge the flag maps of one or more BagOStuff objects into a "lowest common denominator" map.
BagOStuff[] | $bags |
Definition at line 788 of file BagOStuff.php.
Referenced by MultiWriteBagOStuff\__construct(), and ReplicatedBagOStuff\__construct().
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string | $key | |
callable | $callback | Callback method to be executed |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
int | $attempts | The amount of times to attempt a merge in case of failure |
Definition at line 292 of file BagOStuff.php.
References $success, $value, add, cas(), clearLastError(), getLastError(), and getWithToken().
Referenced by MemcachedBagOStuff\merge(), and SqlBagOStuff\merge().
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string | $key | |
callable | $callback | Callback method to be executed |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
int | $attempts | The amount of times to attempt a merge in case of failure |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Definition at line 350 of file BagOStuff.php.
References $success, $value, clearLastError(), getLastError(), lock(), and unlock().
Referenced by merge(), and WinCacheBagOStuff\merge().
BagOStuff::modifySimpleRelayEvent | ( | array | $event | ) |
Modify a cache update operation array for EventRelayer::notify()
This is used for relayed writes, e.g. for broadcasting a change to multiple data-centers. If the array contains a 'val' field then the command involves setting a key to that value. Note that for simplicity, 'val' is always a simple scalar value. This method is used to possibly serialize the value and add any cache-specific key/values needed for the relayer daemon (e.g. memcached flags).
array | $event |
Reimplemented in CachedBagOStuff, MemcachedBagOStuff, and RedisBagOStuff.
Definition at line 675 of file BagOStuff.php.
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abstract |
Set an item.
string | $key | |
mixed | $value | |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
int | $flags | Bitfield of BagOStuff::WRITE_* constants |
Reimplemented in EmptyBagOStuff, WinCacheBagOStuff, RedisBagOStuff, APCBagOStuff, APCUBagOStuff, CachedBagOStuff, HashBagOStuff, MemcachedBagOStuff, MemcachedPeclBagOStuff, MultiWriteBagOStuff, ReplicatedBagOStuff, RESTBagOStuff, and SqlBagOStuff.
Referenced by Wikimedia\Rdbms\ChronologyProtector\shutdown().
BagOStuff::setDebug | ( | $bool | ) |
bool | $bool |
Reimplemented in CachedBagOStuff, MemcachedPhpBagOStuff, MultiWriteBagOStuff, and ReplicatedBagOStuff.
Definition at line 136 of file BagOStuff.php.
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Set the "last error" registry.
int | $err | ERR_* constant |
Definition at line 633 of file BagOStuff.php.
Referenced by MemcachedPeclBagOStuff\checkResult(), RedisBagOStuff\getConnection(), RESTBagOStuff\handleError(), RedisBagOStuff\handleException(), SqlBagOStuff\handleReadError(), and SqlBagOStuff\handleWriteError().
BagOStuff::setLogger | ( | LoggerInterface | $logger | ) |
LoggerInterface | $logger |
Definition at line 129 of file BagOStuff.php.
Referenced by __construct().
BagOStuff::setMockTime | ( | & | $time | ) |
float | null | &$time | Mock UNIX timestamp for testing |
Definition at line 815 of file BagOStuff.php.
References $time.
BagOStuff::setMulti | ( | array | $data, |
$exptime = 0 ) |
Batch insertion.
array | $data | $key => $value assoc array |
int | $exptime | Either an interval in seconds or a unix timestamp for expiry |
Reimplemented in RedisBagOStuff, SqlBagOStuff, and MemcachedPeclBagOStuff.
Definition at line 530 of file BagOStuff.php.
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private |
Track the number of times that a given key has been used.
string | $key |
Definition at line 195 of file BagOStuff.php.
Referenced by get().
BagOStuff::unlock | ( | $key | ) |
Release an advisory lock on a key string.
string | $key |
Reimplemented in CachedBagOStuff, MultiWriteBagOStuff, and ReplicatedBagOStuff.
Definition at line 446 of file BagOStuff.php.
Referenced by getScopedLock(), incr(), mergeViaLock(), and Wikimedia\Rdbms\ChronologyProtector\shutdown().
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Definition at line 57 of file BagOStuff.php.
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Map of (ATTR_* class constant => QOS_* class constant)
Definition at line 77 of file BagOStuff.php.
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Definition at line 71 of file BagOStuff.php.
Referenced by SqlBagOStuff\waitForReplication().
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Definition at line 62 of file BagOStuff.php.
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Definition at line 68 of file BagOStuff.php.
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private |
Definition at line 64 of file BagOStuff.php.
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Definition at line 53 of file BagOStuff.php.
Referenced by MemcachedBagOStuff\makeKeyInternal().
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ERR_* class constant.
Definition at line 51 of file BagOStuff.php.
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Lock tracking.
Definition at line 49 of file BagOStuff.php.
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protected |
Definition at line 55 of file BagOStuff.php.
Referenced by MultiWriteBagOStuff\doWrite().
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Definition at line 66 of file BagOStuff.php.
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protected |
Seconds.
Definition at line 59 of file BagOStuff.php.
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private |
Definition at line 74 of file BagOStuff.php.
const BagOStuff::ERR_NO_RESPONSE = 1 |
Definition at line 81 of file BagOStuff.php.
const BagOStuff::ERR_NONE = 0 |
Possible values for getLastError()
Definition at line 80 of file BagOStuff.php.
const BagOStuff::ERR_UNEXPECTED = 3 |
Definition at line 83 of file BagOStuff.php.
Referenced by MemcachedPeclBagOStuff\checkResult(), RESTBagOStuff\handleError(), RedisBagOStuff\handleException(), SqlBagOStuff\handleReadError(), and SqlBagOStuff\handleWriteError().
const BagOStuff::ERR_UNREACHABLE = 2 |
Definition at line 82 of file BagOStuff.php.
Referenced by RedisBagOStuff\getConnection(), SqlBagOStuff\handleReadError(), and SqlBagOStuff\handleWriteError().
const BagOStuff::READ_LATEST = 1 |
Bitfield constants for get()/getMulti()
Definition at line 86 of file BagOStuff.php.
const BagOStuff::READ_VERIFIED = 2 |
Definition at line 87 of file BagOStuff.php.
const BagOStuff::WRITE_CACHE_ONLY = 2 |
Definition at line 90 of file BagOStuff.php.
const BagOStuff::WRITE_SYNC = 1 |
Bitfield constants for set()/merge()
Definition at line 89 of file BagOStuff.php.
Referenced by MultiWriteBagOStuff\set().