PersistenceCacheStack

PersistenceCacheStack is a C# library that implements a two levels cache allowing at the same time high performance and persistence. PersistenceCacheStack uses the MemoryCache as the first layer and Redis as the second layer.

What can it be used for?

PersistenceCacheStack can be used in all contexts that require fast access to the cache without sacrificing persistence. Through this library you can avoid network time for access to the Redis cache.

How it works

PersistenceCacheStack uses two different cache layers, a first layer in-memory using MemoryCache and a second layer on Redis for persistence. All operations performed in cache will take place on the first in-memory cache layer and will be synchronized with the fire-and-forget pattern, with Redis. This logic allows the data to be obtained immediately without waiting for any network latency. On the other hand, the system changes from a strong consistency to eventually consistency in a multi-node context. In fact, a cached data may not be updated to the version of the other nodes but eventually it will be aligned.

Architecture

Redis

PersistenceCacheStack uses the StackExchange.Redis and StackExchange.Redis.Extensions to wrap the CRUD operations towars Redis. You can find all the references to the projects in this file.

Installation

To install the PersistenceCacheStack library just add the dll reference and its dependencies. All dependencies are embedded with Costura.Fody.

How to configure it

To configure the library just set access to Redis for persistence.

Here the example of an App.config file

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <section name="redisCacheClient" type="StackExchange.Redis.Extensions.LegacyConfiguration.RedisCachingSectionHandler, StackExchange.Redis.Extensions.LegacyConfiguration" />
  </configSections>
  <redisCacheClient allowAdmin="true" ssl="false" connectTimeout="3000" database="24">
    <serverEnumerationStrategy mode="Single" targetRole="PreferSlave" unreachableServerAction="IgnoreIfOtherAvailable" />
    <hosts>
      <add host="127.0.0.1" cachePort="6379" />
    </hosts>
  </redisCacheClient>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-11.0.0.0" newVersion="11.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
</configuration>

Serialization

In order to store a class into Redis, that class must be serializable. PersistenceCacheStack uses the PersistenceCacheStackEntity object to incapsulate the <key, value> couple and checks if the object is actually serializable into the constructor.

Usage

To use the PersistenceCacheStack library, just instantiate a PersistenceCacheStackClient object specifying the type of object it will work on. The instance constructor receives a flag to request auto synchronization from Redis.

var persistenceCacheStack = new PersistenceCacheStackClient<T>(true);

at this point the CRUD operations can be performed. For example, below how to add an object of type string inside the cache with no expiration:

var persistenceCacheStack = new PersistenceCacheStackClient<string>(true);
var addResult = persistenceCacheStack.AddItem("Key", "AddItemString", null);

To explicit synchronize the in-memory cache with Redis use the following instruction:

persistenceCacheStack.SynchFromRedis();

in this way all the persistent objects on Redis will be copied in the first cache layer.

StackExchange.Redis Reference

https://github.com/StackExchange/StackExchange.Redis

StackExchange.Redis.Extensions Reference

https://github.com/imperugo/StackExchange.Redis.Extensions

Contributing

Thank you for considering to help out with the source code! We welcome contributions from anyone on the internet, and are grateful for even the smallest of fixes! If you'd like to contribute, please fork, fix, commit and send a pull request for the maintainers to review and merge into the main code base.

Getting started with Git and GitHub

• Setting up Git for Windows and connecting to GitHub
• Forking a GitHub repository
• The simple guide to GIT guide
• Open an issue if you encounter a bug or have a suggestion for improvements/features

Licensee

PersistenceCacheStack source code is available under GNU General Public License v3.0, see license in the source. https://www.gnu.org/licenses/gpl-3.0.en.html

Contact

Please contact at francesco.delre.87[at]gmail.com for any details.