Pluggable Runtime Cache
|
Product version: |
EPiServer CMS 5 R1 |
|
Document version: |
1.0 |
|
Document creation date: |
23-11-2006 |
Purpose
The purpose of the pluggable cache is to allow partner developers to replace the runtime cache used by EPiServer CMS 5 with their own custom implementation.
Table of Contents
In EPiServer CMS 5 it is possible for partner developers to replace the cache functionality used by EPiServer CMS with their own customized plug-ins.
The class EPiServer.CacheManager has been expanded with a RuntimeCache property to allow developers to access an instance of the runtime cache. The following static helper functions have also been added to this class:
|
Original function |
New function |
|
HttpRuntime.Cache.Insert(…) |
CacheManager.RuntimeCacheInsert(…) |
|
HttpRuntime.Cache.Add(…) |
CacheManager.RuntimeCacheAdd(…) |
|
HttpRuntime.Cache.Remove(…) |
CacheManager.RuntimeCacheRemove(…) |
|
HttpRuntime.Cache.Get(…) |
CacheManager.RuntimeCacheGet(…) |
To implement a custom cache, the interface EPiServer.BaseLibrary.IRuntimeCache must be implemented.
Remarks:
When several modules use the same cache, each module will create an instance of the cache object. If you intend them to use the same cache, you must implement a singleton pattern for it.
Example of implementation of “logging cache”.
using System;
using System.Web;
using System.Web.Caching;
using EPiServer;
using EPiServer.BaseLibrary;
using log4net;
public class LoggedHttpRuntimeCache : IRuntimeCache
{
private static readonly ILog log =
LogManager.GetLogger(typeof(LoggedHttpRuntimeCache));
public void Insert(string key, object value, CacheDependency dependencies,
DateTime absoluteExpiration, TimeSpan slidingExpiration,
CacheItemPriority priority, CacheItemRemovedCallback onRemoveCallback)
{
log.Debug("LogInsert:" + key);
HttpRuntime.Cache.Insert(key, value, dependencies, absoluteExpiration,
slidingExpiration, priority, onRemoveCallback);
}
public object Add(string key, object value, CacheDependency dependencies,
DateTime absoluteExpiration, TimeSpan slidingExpiration,
CacheItemPriority priority, CacheItemRemovedCallback onRemoveCallback)
{
log.Debug("LogAdd:" + key);
return HttpRuntime.Cache.Add(key, value, dependencies,
absoluteExpiration, slidingExpiration, priority,
onRemoveCallback);
}
public void Remove(string key)
{
log.Debug("LogRemove:" + key);
HttpRuntime.Cache.Remove(key);
}
public object Get(string key)
{
log.Debug("LogGet:" + key);
return HttpRuntime.Cache.Get(key);
}
#endregion
}
Plug in the custom cache by adding the following rows to the Web.Config file of your site:
<configuration>
<configSections>
<section name="episerver.baseLibrary"
allowDefinition="MachineToApplication"
allowLocation="false"
type="EPiServer.BaseLibrary.ConfigurationHandler,EPiServer.BaseLibrary" />
</configSections>
.
.
.
<episerver.baseLibrary>
<classFactories>
<add
type="EPiServer.Implementation.DefaultBaseLibraryFactory, EPiServer.Implementation"
id="EPiServerRuntime" >
<assignStatic
type="EPiServer.BaseLibrary.ClassFactory"
property="Instance" />
<register
type="EPiServer.BaseLibrary.IRuntimeCache, EPiServer.BaseLibrary"
mappedType="EPiServerSample.CustomCache.LoggedHttpRuntimeCache, EPiServerSample" />
</add>
</classFactories>
</episerver.baseLibrary>
