// Copyright (C) 2024 Vaughn Nugent
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see .
using System;
using System.Threading;
using System.Threading.Tasks;
using VNLib.Net.Http;
using VNLib.Data.Caching;
using VNLib.Plugins;
using VNLib.Plugins.Extensions.Loading;
using VNLib.Plugins.Extensions.VNCache;
using VNLib.Plugins.Extensions.VNCache.DataModel;
namespace SimpleBookmark.Cache
{
[ConfigurationName("search_cache", Required = false)]
internal sealed class SearchResultCache
{
private readonly IEntityCache? _cache;
///
/// Gets a value that indicates if the configuration enabled result caching
///
public bool IsEnabled => _cache != null;
public SearchResultCache(PluginBase plugin) : this(plugin, null)
{ }
public SearchResultCache(PluginBase plugin, IConfigScope? config)
{
string? cachePrefix = config?.GetRequiredProperty("cachePrefix", p => p.GetString()!);
bool isEnabled = config?.GetRequiredProperty("enabled", p => p.GetBoolean()) ?? true;
if (!isEnabled)
{
return;
}
IGlobalCacheProvider? cache = plugin.GetDefaultGlobalCache();
if (cache != null)
{
if (cachePrefix != null)
{
_cache = cache.GetPrefixedCache(cachePrefix)
.CreateEntityCache(
new MemPackCacheSerializer(null),
new MemPackCacheSerializer(null)
);
}
else
{
//non-prefixed cache
_cache = cache.CreateEntityCache(
new MemPackCacheSerializer(null),
new MemPackCacheSerializer(null)
);
}
}
}
public async Task GetCachedResultAsync(string[] keys, CancellationToken cancellation)
{
ResultCacheEntry? entry = await _cache!.GetAsync($"{keys}", cancellation);
return entry is null ? null : new ResultResponseReader(entry);
}
public Task StoreResultAsync(Memory data, string[] keys, CancellationToken cancellation)
{
//Init new entry
ResultCacheEntry entry = new()
{
Payload = data,
Created = DateTime.UtcNow
};
return _cache!.UpsertAsync($"{keys}", entry, cancellation);
}
public Task DeleteEntry(string[] keys, CancellationToken cancellation) => _cache!.RemoveAsync($"{keys}", cancellation);
private sealed class ResultResponseReader(ResultCacheEntry entry) : IMemoryResponseReader
{
private int _position;
///
public int Remaining => entry.Payload.Length - _position;
///
public void Advance(int written) => _position += written;
///
public void Close() => entry.Dispose();
///
public ReadOnlyMemory GetMemory() => entry.Payload.Slice(_position);
}
}
}