wangle::FilePersistentCache< K, V, M > Class Template Reference

#include <FilePersistentCache.h>

Inheritance diagram for wangle::FilePersistentCache< K, V, M >:

Public Member Functions
	FilePersistentCache (const std::string &file, std::size_t cacheCapacity, std::chrono::seconds syncInterval=std::chrono::duration_cast< std::chrono::seconds >(client::persistence::DEFAULT_CACHE_SYNC_INTERVAL), int nSyncRetries=client::persistence::DEFAULT_CACHE_SYNC_RETRIES)
	FilePersistentCache (std::shared_ptr< folly::Executor > executor, const std::string &file, std::size_t cacheCapacity, std::chrono::seconds syncInterval, int nSyncRetries)
	~FilePersistentCache () override
folly::Optional< V >	get (const K &key) override
void	put (const K &key, const V &val) override
bool	remove (const K &key) override
void	clear (bool clearPersistence=false) override
size_t	size () override
void	setSyncOnDestroy (bool syncOnDestroy)
Public Member Functions inherited from wangle::PersistentCache< K, V >
virtual	~PersistentCache ()

Private Attributes
LRUPersistentCache< K, V, M >::Ptr	cache_

Detailed Description

template<typename K, typename V, typename M = std::mutex>
class wangle::FilePersistentCache< K, V, M >

A PersistentCache implementation that used a regular file for storage. In memory structure fronts the file and the cache operations happen on it. Loading from and syncing to file are hidden from clients. Sync to file happens asynchronously on a separate thread at a configurable interval. Syncs to file on destruction as well.

NOTE NOTE NOTE: Although this class aims to be a cache for arbitrary, it relies heavily on folly::toJson, folly::dynamic and convertTo for serialization and deserialization. So It may not suit your need until true support arbitrary types is written.

Definition at line 40 of file FilePersistentCache.h.

Constructor & Destructor Documentation

template<typename K , typename V , typename M >

wangle::FilePersistentCache< K, V, M >::FilePersistentCache	(	const std::string &	file,
		std::size_t	cacheCapacity,
		std::chrono::seconds	syncInterval = std::chrono::duration_cast<std::chrono::seconds>(              client::persistence::DEFAULT_CACHE_SYNC_INTERVAL),
		int	nSyncRetries = client::persistence::DEFAULT_CACHE_SYNC_RETRIES
	)

Definition at line 114 of file FilePersistentCache-inl.h.

    : cache_(std::make_shared<LRUPersistentCache<K, V, M>>(
          cacheCapacity,
          std::chrono::duration_cast<std::chrono::milliseconds>(syncInterval),
          nSyncRetries,
          std::make_unique<FilePersistenceLayer<K, V>>(file))) {}

template<typename K , typename V , typename M >

wangle::FilePersistentCache< K, V, M >::FilePersistentCache	(	std::shared_ptr< folly::Executor >	executor,
		const std::string &	file,
		std::size_t	cacheCapacity,
		std::chrono::seconds	syncInterval,
		int	nSyncRetries
	)

Definition at line 126 of file FilePersistentCache-inl.h.

    : cache_(std::make_shared<LRUPersistentCache<K, V, M>>(
          std::move(executor),
          cacheCapacity,
          std::chrono::duration_cast<std::chrono::milliseconds>(syncInterval),
          nSyncRetries,
          std::make_unique<FilePersistenceLayer<K, V>>(file))) {}

template<typename K, typename V, typename M = std::mutex>

wangle::FilePersistentCache< K, V, M >::~FilePersistentCache ( )

inlineoverride

Definition at line 58 of file FilePersistentCache.h.

{}

Member Function Documentation

template<typename K, typename V, typename M = std::mutex>

void wangle::FilePersistentCache< K, V, M >::clear ( bool  clearPersistence = false )

inlineoverridevirtual

Empty the contents of the cache

Implements wangle::PersistentCache< K, V >.

Definition at line 75 of file FilePersistentCache.h.

References wangle::FilePersistentCache< K, V, M >::cache_, and wangle::LRUPersistentCache< K, V, MutexT >::clear().

                                                     {
    cache_->clear(clearPersistence);
  }

template<typename K, typename V, typename M = std::mutex>

folly::Optional<V> wangle::FilePersistentCache< K, V, M >::get ( const K &  key )

inlineoverridevirtual

PersistentCache operations

Implements wangle::PersistentCache< K, V >.

Definition at line 63 of file FilePersistentCache.h.

References wangle::FilePersistentCache< K, V, M >::cache_, and wangle::LRUPersistentCache< K, V, MutexT >::get().

Referenced by TYPED_TEST().

                                              {
    return cache_->get(key);
  }

template<typename K, typename V, typename M = std::mutex>

void wangle::FilePersistentCache< K, V, M >::put ( const K &  key, const V &  val  )

inlineoverridevirtual

Set a value corresponding to a key

Parameters

key	string, the key to set
val	string, the value to set

overwrites value if key has a value associated in the cache

Implements wangle::PersistentCache< K, V >.

Definition at line 67 of file FilePersistentCache.h.

References wangle::FilePersistentCache< K, V, M >::cache_, and wangle::LRUPersistentCache< K, V, MutexT >::put().

Referenced by TYPED_TEST().

                                                {
    cache_->put(key, val);
  }

template<typename K, typename V, typename M = std::mutex>

bool wangle::FilePersistentCache< K, V, M >::remove ( const K &  key )

inlineoverridevirtual

Clear a cache entry associated with a key

Parameters

key	string, the key to lookup and clear

Returns

boolean true if any elements are removed, else false

Implements wangle::PersistentCache< K, V >.

Definition at line 71 of file FilePersistentCache.h.

References wangle::FilePersistentCache< K, V, M >::cache_, and wangle::LRUPersistentCache< K, V, MutexT >::remove().

                                     {
    return cache_->remove(key);
  }

template<typename K, typename V, typename M = std::mutex>

void wangle::FilePersistentCache< K, V, M >::setSyncOnDestroy ( bool  syncOnDestroy )

inline

Definition at line 83 of file FilePersistentCache.h.

References wangle::FilePersistentCache< K, V, M >::cache_, and wangle::LRUPersistentCache< K, V, MutexT >::setSyncOnDestroy().

                                            {
    cache_->setSyncOnDestroy(syncOnDestroy);
  }

template<typename K, typename V, typename M = std::mutex>

size_t wangle::FilePersistentCache< K, V, M >::size ( )

inlineoverridevirtual

return the size of the cache

Returns

size_t, the size of the cache

Implements wangle::PersistentCache< K, V >.

Definition at line 79 of file FilePersistentCache.h.

References wangle::FilePersistentCache< K, V, M >::cache_, and wangle::LRUPersistentCache< K, V, MutexT >::size().

Referenced by TYPED_TEST().

                         {
    return cache_->size();
  }

Member Data Documentation

template<typename K, typename V, typename M = std::mutex>

LRUPersistentCache<K, V, M>::Ptr wangle::FilePersistentCache< K, V, M >::cache_

private

Definition at line 88 of file FilePersistentCache.h.

Referenced by wangle::FilePersistentCache< K, V, M >::clear(), wangle::FilePersistentCache< K, V, M >::get(), wangle::FilePersistentCache< K, V, M >::put(), wangle::FilePersistentCache< K, V, M >::remove(), wangle::FilePersistentCache< K, V, M >::setSyncOnDestroy(), and wangle::FilePersistentCache< K, V, M >::size().

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The documentation for this class was generated from the following files:

• proxygen/wangle/wangle/client/persistence/FilePersistentCache.h
• proxygen/wangle/wangle/client/persistence/FilePersistentCache-inl.h