Dynamic rate limit plugin

Plugins/BTCPayServer.Plugins.DynamicRateLimits/DynamicRateLimitsService.cs

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+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Threading;
+using System.Threading.Tasks;
+using BTCPayServer.Abstractions.Contracts;
+using Microsoft.Extensions.Hosting;
+using NicolasDorier.RateLimits;
+
+namespace BTCPayServer.Plugins.DynamicRateLimits;
+
+public class DynamicRateLimitsService : IHostedService
+{
+    private readonly ISettingsRepository _settingsRepository;
+    private readonly RateLimitService _rateLimitService;
+    public IEnumerable<string> OriginalLimits { get; private set;  }
+
+    public DynamicRateLimitsService(ISettingsRepository  settingsRepository, RateLimitService rateLimitService)
+    {
+        _settingsRepository = settingsRepository;
+        _rateLimitService = rateLimitService;
+    }
+        
+    public async Task StartAsync(CancellationToken cancellationToken)
+    {
+        OriginalLimits =
+            ((ConcurrentDictionary<string, LimitRequestZone>) _rateLimitService.GetType()
+                .GetField("_Zones", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(_rateLimitService))
+            .Values.Select(zone => zone.ToString());
+            
+        var settings = await _settingsRepository.GetSettingAsync<DynamicRateLimitSettings>();
+        if (settings?.RateLimits is not null)
+        {
+            foreach (var limit in settings.RateLimits)
+            {
+                _rateLimitService.SetZone(limit);
+            }
+        }
+    }
+
+    public async Task<DynamicRateLimitSettings> Get()
+    {
+        
+        return  (await _settingsRepository.GetSettingAsync<DynamicRateLimitSettings>())?? new DynamicRateLimitSettings();
+    }
+
+    public async Task UseDefaults()
+    {
+        foreach (var originalLimit in OriginalLimits)
+        {
+            _rateLimitService.SetZone(originalLimit);
+        }
+
+        await _settingsRepository.UpdateSetting(new DynamicRateLimitSettings());
+    }
+
+    public async Task Update(string[] limits)
+    {
+        foreach (var originalLimit in OriginalLimits)
+        {
+            _rateLimitService.SetZone(originalLimit);
+        }
+        foreach (var limit in limits)
+        {
+            _rateLimitService.SetZone(limit);
+        }
+            
+        await _settingsRepository.UpdateSetting(new DynamicRateLimitSettings()
+        {
+            RateLimits = limits
+        });
+    }
+        
+        
+
+    public Task StopAsync(CancellationToken cancellationToken)
+    {
+        return Task.CompletedTask;
+    }
+}