GroupDocs.Viewer.UI.Sample.CustomCacheProvider

Custom Cache Provider Sample

This sample demonstrates how to implement and register a custom IFileCache provider, replacing the built-in local or in-memory cache with your own caching logic.

What This Sample Shows

• Implementing the IFileCache interface with a custom ConcurrentDictionaryFileCache
• Registering the custom cache provider after AddGroupDocsViewerSelfHostApi() to override the default
• In-memory caching using ConcurrentDictionary as the backing store

Prerequisites

• .NET 8.0 SDK or later

Running

cd samples/GroupDocs.Viewer.UI.Sample.CustomCacheProvider
dotnet run

Open your browser at https://localhost:5001 (or the URL shown in the console output).

Configuration

The custom cache is registered as a singleton after the self-host API setup:

builder.Services
    .AddControllers()
    .AddGroupDocsViewerSelfHostApi(config => { ... })
    .AddLocalStorage("./Files");

// Register custom cache AFTER AddGroupDocsViewerSelfHostApi()
builder.Services.AddSingleton<IFileCache, ConcurrentDictionaryFileCache>();

Important: The custom IFileCache registration must come after AddGroupDocsViewerSelfHostApi() to override the default cache implementation.

Implementing IFileCache

The IFileCache interface requires four methods:

public interface IFileCache
{
    TEntry TryGetValue<TEntry>(string cacheKey, string filePath);
    Task<TEntry> TryGetValueAsync<TEntry>(string cacheKey, string filePath);
    void Set<TEntry>(string cacheKey, string filePath, TEntry entry);
    Task SetAsync<TEntry>(string cacheKey, string filePath, TEntry entry);
}

This pattern can be adapted to use Redis, database, or any other caching backend.