RavenDB ASP.NET Data Protection Repository

DataProtectionBuilderExtensions.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Globalization;
using System.Linq;
using System.Xml.Linq;
using Microsoft.AspNetCore.DataProtection.KeyManagement;
using Microsoft.AspNetCore.DataProtection.Repositories;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
using Raven.Client.Documents;
using Raven.Client.Documents.Session;

namespace Microsoft.AspNetCore.DataProtection
{
    public static class DataProtectionBuilderExtensions
    {
        public static IDataProtectionBuilder PersistKeysToRaven(this IDataProtectionBuilder builder)
        {
            if (builder == null)
            {
                throw new ArgumentNullException(nameof(builder));
            }

            builder.Services.AddSingleton<IConfigureOptions<KeyManagementOptions>>(services =>
            {
                var store = services.GetRequiredService<IDocumentStore>();

                return new ConfigureOptions<KeyManagementOptions>(options =>
                {
                    options.XmlRepository = new RavenXmlRepository(store);
                });
            });

            return builder;
        }

        class RavenXmlRepository : IXmlRepository
        {
            private readonly IDocumentStore store;

            public RavenXmlRepository(IDocumentStore store)
            {
                this.store = store;
            }

            public IReadOnlyCollection<XElement> GetAllElements()
            {
                using var session = store.OpenSession();

                var docs = session.Advanced
                    .LoadStartingWith<XmlDocument>(CollectionName + "/",
                        pageSize: int.MaxValue);

                return new ReadOnlyCollection<XElement>(
                    docs.Select(x => XElement.Parse(x.SerializedXml)).ToArray());
            }

            public void StoreElement(XElement element, string friendlyName)
            {
                string? id = element.Attribute("id")?.Value;

                if (id == null 
                    || !DateTime.TryParse(element.Element("expirationDate")?.Value, null, DateTimeStyles.AssumeUniversal, out var expirationDate))
                {
                    throw new NotSupportedException($"Not supported Xml: {element}");
                }

                using var session = store.OpenSession();

                var document = new XmlDocument
                {
                    Id = $"{CollectionName}/{id}",
                    SerializedXml = element.ToString()
                };

                session.Store(document);

                var metadata = session.Advanced.GetMetadataFor(document);
                
                meta[Constants.Documents.Metadata.Expires] = expirationDate;

                session.SaveChanges();
            }

            private const string CollectionName = "XmlDocuments";

            class XmlDocument
            {
                public string Id { get; set; } = null!;

                public string SerializedXml { get; set; } = null!;
            }
        }
    }
}