Include packaging settings

RAIC.Extensions.Configuration.EntityFrameworkCore.PostgreSQL/PostgreSQLNotificationConfigurationReloader.cs

@@ -52,22 +52,29 @@ internal class PostgreSQLNotificationConfigurationReloader : Microsoft.Extension
     {
         var dbConnection = Initialise();
 
-        do
+        try
         {
             await ListenForNotifications(stoppingToken);
 
-            try
+            do
             {
-                await dbConnection.WaitAsync(stoppingToken);
+                try
+                {
+                    await dbConnection.WaitAsync(stoppingToken);
+                }
+                catch (Exception e) when (e is not OperationCanceledException)
+                {
+                    _logger?.LogWarning(e, "Exception while waiting for notifications on channel '{channel}'", _options.ChannelName);
+                }
             }
-            catch (Exception e) when (e is not TaskCanceledException)
+            while (ConnectionState.Open == dbConnection.State || await TryReconnect(stoppingToken));
-            {
-                _logger?.LogWarning(e, "Exception while waiting for notifications on channel '{channel}'", _options.ChannelName);
-            }
-        }
-        while (await IsReconnectionPossible(stoppingToken));
 
-        _logger?.LogWarning("Giving up listening for notifications on channel '{channel}' because reconnection attempts exhausted. Configuration updates from database will no longer occur", _options.ChannelName);
+            _logger?.LogWarning("Giving up listening for notifications on channel '{channel}' because reconnection attempts exhausted. Configuration updates from database will no longer occur", _options.ChannelName);
+        }
+        catch (OperationCanceledException e)
+        {
+            _logger?.LogInformation(e, "Exiting due to signal from stopping token");
+        }
     }
 
     private Npgsql.NpgsqlConnection Initialise()
@@ -76,8 +83,37 @@ internal class PostgreSQLNotificationConfigurationReloader : Microsoft.Extension
         dbConnection.Notification += OnNotification;
 
         return dbConnection;
+
+        void OnNotification(object sender, Npgsql.NpgsqlNotificationEventArgs args)
+        {
+            _logger?.LogTrace("Received notification '{payload}' on channel '{channel}'", args.Payload, args.Channel);
+            if (args.Channel != _options.ChannelName)
+                return;
+
+            using (var previousCts = Interlocked.Exchange(ref _cts, new()))
+            {
+                previousCts.Cancel();
+            }
+
+            ReadOnlySpan<string> keyValue = args.Payload.Split('=', 2); // DEBT: Do split without heap allocation
+            switch (keyValue.Length)
+            {
+                case 2:
+                    _configProvider.Set(keyValue[0], keyValue[1]);
+                    break;
+                case 1:
+                    _configProvider.Remove(keyValue[0]);
+                    break;
+                default:
+                    _logger?.LogWarning("Invalid '{channel}' payload '{payload}'", args.Channel, args.Payload);
+                    return; // Don't proceed to debounced reload
+            }
+
+            _ = DebouncedProviderReload(); // Intentionally running without awaiting, may be cancelled
+        }
     }
 
+
     private async Task ListenForNotifications(CancellationToken stoppingToken)
     {
         var listenStatement = $"LISTEN {_options.ChannelName}";
@@ -86,46 +122,18 @@ internal class PostgreSQLNotificationConfigurationReloader : Microsoft.Extension
         _logger?.LogInformation("Listening for notifications on channel '{channel}'", _options.ChannelName);
     }
 
-    private void OnNotification(object sender, Npgsql.NpgsqlNotificationEventArgs args)
-    {
-        _logger?.LogTrace("Received notification '{payload}' on channel '{channel}'", args.Payload, args.Channel);
-        if (args.Channel != _options.ChannelName)
-            return;
-
-        using (var previousCts = Interlocked.Exchange(ref _cts, new()))
-        {
-            previousCts.Cancel();
-        }
-
-        ReadOnlySpan<string> keyValue = args.Payload.Split('=', 2); // DEBT: Do split without heap allocation
-        switch (keyValue.Length)
-        {
-            case 2:
-                _configProvider.Set(keyValue[0], keyValue[1]);
-                break;
-            case 1:
-                _configProvider.Remove(keyValue[0]);
-                break;
-            default:
-                _logger?.LogWarning("Invalid '{channel}' payload '{payload}'", args.Channel, args.Payload);
-                return; // Don't proceed to debounced reload 
-        }
-
-        var _ = DebouncedProviderReload(); // Intentionally running without awaiting, may be cancelled
-    }
-
 
     /// <summary>
     /// Trigger reload of the <see cref="IEntityFrameworkCoreDbSetConfigurationProvider"/> after waiting for a [cancelable] debounce period
     /// </summary>
     /// <remarks>Does not log <see cref="TaskCanceledException "/> each time debounce task is cancelled, unlike <see cref="SimpleDebouncedProviderReload"/></remarks>
-    private async ValueTask DebouncedProviderReload()
+    private async Task DebouncedProviderReload()
     {
         var delayTask = Task.Delay(_options.DebounceInterval);
         var cancelableTask = Task.Delay(Timeout.Infinite, _cts.Token);
         var completedTask = await Task.WhenAny(delayTask, cancelableTask).ConfigureAwait(false);
 
-        if (completedTask == delayTask) // If the completed task is the delayTask, we reached debounce delay, proceed with reload
+        if (ReferenceEquals(completedTask, delayTask)) // If the completed task is the delayTask, we reached debounce delay, proceed with reload
         {
             _configProvider.OnReload();
         }
@@ -154,7 +162,7 @@ internal class PostgreSQLNotificationConfigurationReloader : Microsoft.Extension
     }
 
 
-    private async Task<bool> IsReconnectionPossible(CancellationToken stoppingToken)
+    private async Task<bool> TryReconnect(CancellationToken stoppingToken)
     {
         await Task.Delay(_options.InitialReconnectionDelay, stoppingToken);
 
@@ -165,16 +173,21 @@ internal class PostgreSQLNotificationConfigurationReloader : Microsoft.Extension
             var backoffTask = Task.Delay(_options.InitialReconnectionDelay * (1 << i), stoppingToken);
             var completedTask = await Task.WhenAny(backoffTask, canConnectTask);
 
-            if (completedTask == canConnectTask) // connect finished first
+            if (ReferenceEquals(completedTask, backoffTask)) // backoff finished first
             {
-                if (await canConnectTask) return true; // if can connect return immediately
+                continue; // Assume connection task has failed
-                await backoffTask; // connect failed, wait for backoff time before trying again
             }
-            else // backoff finished first, wait for connection task result before decided whether to go around again or return immediately
+
+            // can connect task finished first
+            if (await canConnectTask) // if it finished with success
             {
-                if (await canConnectTask) return true;
+                await ListenForNotifications(stoppingToken);
+                return true;
             }
+
+            await backoffTask; // connect failed, wait for backoff time before trying again
         }
+
         return false;
     }
 

RAIC.Extensions.Configuration.EntityFrameworkCore.PostgreSQL/RAIC.Extensions.Configuration.EntityFrameworkCore.PostgreSQL.csproj

@@ -6,6 +6,17 @@
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
+  <PropertyGroup>
+    <PackageId>RAIC.Extensions.Configuration.EntityFrameworkCore.PostgreSQL</PackageId>
+    <Version>0.1.1</Version>
+    <Authors>Rhys Ickeringill</Authors>
+    <Description>Adds "reload on change" support to RAIC.Extensions.Configuration.EntityFrameworkCore for PostgreSQL</Description>
+    <PackageTags>configuration;entityframeworkcore;postgresql</PackageTags>
+    <RepositoryUrl>https://git.raickeringill.id.au/ickers/Extensions.Configuration.EntityFrameworkCore</RepositoryUrl>
+    <PackageLicenseExpression>MIT</PackageLicenseExpression>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+  </PropertyGroup>
+	
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Options.DataAnnotations" Version="[8.0, 11.0)" />
     <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="[8.0, 11.0)" />
@@ -16,4 +27,8 @@
     <ProjectReference Include="..\RAIC.Extensions.Configuration.EntityFrameworkCore\RAIC.Extensions.Configuration.EntityFrameworkCore.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <None Include="README.md" Pack="true" PackagePath="\" />
+  </ItemGroup>
+
 </Project>

RAIC.Extensions.Configuration.EntityFrameworkCore.PostgreSQL/README.md

@@ -5,8 +5,8 @@ This library enhances `RAIC.Extensions.Configuration.EntityFrameworkCore` with s
 
 ## Goals
 1. No polling!
-1. Updates happen in background via worker service (`IHostedService`)
+1. Updates happen in background via a [hosted service](https://learn.microsoft.com/en-us/aspnet/core/fundamentals/host/hosted-services) implementation.
-1. Only update settings which change rather than reloading all of them
+1. Only update settings which change rather than updating them all
 
 ## Requirements
 * .NET 8
@@ -14,8 +14,8 @@ This library enhances `RAIC.Extensions.Configuration.EntityFrameworkCore` with s
 ## Gotchas
 * Setting values cannot be `null` (as signified by the `RequiredAttribute` on `ISetting.Value`)
 * Setting keys must not contain the `=` character (similar to `CommandLineConfigurationProvider` & `EnvironmentVariablesConfigurationProvider`)
-* Small window of opportunity for updates to be missed during reconnection process
+* Small window of opportunity for updates to be missed during reconnection process after any network dropouts or other connectivity flakiness
-* Consider adding `Keepalive` to your conenction string (https://www.npgsql.org/doc/keepalive.html) if its not already present
+* Consider adding `Keepalive` [parameter](https://www.npgsql.org/doc/keepalive.html) to your connection string if its not already present
 
 ## Known Issues
 * Not tested under load
@@ -65,7 +65,7 @@ AFTER DELETE ON settings
 FOR EACH ROW EXECUTE FUNCTION notify_setting_remove();
 ```
 
-Reccommend adding your SQL to the migration which adds the `Settings` table/view (or a new migration if that table/view already exists).
+Recommend adding your SQL to the migration which adds the `Settings` table/view (or a new migration if that table/view already exists).
 
 ## Usage Example
 
@@ -84,9 +84,11 @@ public record Setting : ISetting
     public required string Value { get; set; }
 }
 
-public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options), ISettingsDbContext<DbSet<Setting>, Setting>
+public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options), ISettingsDbContext<DbSet<Setting>>, ISettingsDbContextFactory<MyDbContext>
 {
     public DbSet<Setting> Settings { get; set; }
+
+    public static MyDbContext Create(DbContextOptions<MyDbContext> options) => new(options);
 }
 
 
@@ -97,11 +99,11 @@ builder.Configuration.AddJsonFile("appsettings.json")
                      ...
                      .AddUserSecrets<Program>(); // or wherever your connection string lives
 
-builder.Configuration.AddDbSet<MyDbContext, Setting>(dbContextOptions => dbContextOptions.UseNpgsql(builder.Configuration.GetConnectionString("Default")));
+builder.Configuration.AddDbContext<MyDbContext>(dbContextOptions => dbContextOptions.UseNpgsql(builder.Configuration.GetConnectionString("Default")));
 
 ...
 // Add the PostgreSQLNotificationConfigurationReloader background service and supporting services to obtain setting reloading functionalty
-builder.Services.AddPostgreSQLNotificationConfigurationReloadService<SettingsDbContext>(); // uses default settings, other overrides exist - see code docs
+builder.Services.AddPostgreSQLNotificationConfigurationReloadService<MyDbContext>(); // uses default settings, other overrides exist - see code docs
 
 await builder.Build().RunAsync(); // use config as normal
 

RAIC.Extensions.Configuration.EntityFrameworkCore.SqlServer/Extensions/ServiceCollectionExtensions.cs

@@ -19,7 +19,7 @@ public static class ServiceCollectionExtensions
     /// <remarks>If your connection string contains a password then this method may not work, please use another overload</remarks>
     /// <exception cref="NullReferenceException">If your <typeparamref name="TDbContext"/> does not have a connection string</exception>
     public static IServiceCollection AddSqlServerNotificationConfigurationReloadService<TDbContext, TSetting>(this IServiceCollection services)
-        where TDbContext : DbContext, ISettingsDbContext<DbSet<TSetting>, TSetting>
+        where TDbContext : DbContext, ISettingsDbContext<IQueryable<TSetting>>
         where TSetting : class, ISetting
     {
         var optionsBuilder = services.AddCoreServices<TDbContext, TSetting>();
@@ -49,7 +49,7 @@ public static class ServiceCollectionExtensions
     /// </param>
     /// <returns>The service collection it was called on now with added services</returns>
     public static IServiceCollection AddSqlServerNotificationConfigurationReloadService<TDbContext, TSetting>(this IServiceCollection services, Action<Options> configure)
-        where TDbContext : DbContext, ISettingsDbContext<DbSet<TSetting>, TSetting>
+        where TDbContext : DbContext, ISettingsDbContext<IQueryable<TSetting>>
         where TSetting : class, ISetting
     {
         var optionsBuilder = services.AddCoreServices<TDbContext, TSetting>();
@@ -61,7 +61,7 @@ public static class ServiceCollectionExtensions
 
 
     private static OptionsBuilder<Options> AddCoreServices<TDbContext, TSetting>(this IServiceCollection services)
-        where TDbContext : DbContext, ISettingsDbContext<DbSet<TSetting>, TSetting>
+        where TDbContext : DbContext, ISettingsDbContext<IQueryable<TSetting>>
         where TSetting : class, ISetting
     {
         services.AddSingleton(static provider =>

RAIC.Extensions.Configuration.EntityFrameworkCore.SqlServer/RAIC.Extensions.Configuration.EntityFrameworkCore.SqlServer.csproj

@@ -5,15 +5,29 @@
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
   </PropertyGroup>
+	
+  <PropertyGroup>
+    <PackageId>RAIC.Extensions.Configuration.EntityFrameworkCore.SqlServer</PackageId>
+    <Version>0.1.1</Version>
+    <Authors>Rhys Ickeringill</Authors>
+    <Description>Adds "reload on change" support to RAIC.Extensions.Configuration.EntityFrameworkCore for Microsoft SQL Server</Description>
+    <PackageTags>configuration;entityframeworkcore;mssql</PackageTags>
+    <RepositoryUrl>https://git.raickeringill.id.au/ickers/Extensions.Configuration.EntityFrameworkCore</RepositoryUrl>
+	<PackageLicenseExpression>MIT</PackageLicenseExpression>
+    <PackageReadmeFile>README.md</PackageReadmeFile>
+  </PropertyGroup>
 
-	<ItemGroup>
+  <ItemGroup>
-		<PackageReference Include="Microsoft.Data.SqlClient" Version="[6.0, 7.0)" />
+	<PackageReference Include="Microsoft.Data.SqlClient" Version="[6.0, 7.0)" />
-		<PackageReference Include="Microsoft.Extensions.Options.DataAnnotations" Version="[8.0, 11.0)" />
+	<PackageReference Include="Microsoft.Extensions.Options.DataAnnotations" Version="[8.0, 11.0)" />
-		<PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="[8.0, 11.0)" />
+	<PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="[8.0, 11.0)" />
-	</ItemGroup>
+  </ItemGroup>
 
-	<ItemGroup>
+  <ItemGroup>
-		<ProjectReference Include="..\RAIC.Extensions.Configuration.EntityFrameworkCore\RAIC.Extensions.Configuration.EntityFrameworkCore.csproj" />
+    <ProjectReference Include="..\RAIC.Extensions.Configuration.EntityFrameworkCore\RAIC.Extensions.Configuration.EntityFrameworkCore.csproj" />
-	</ItemGroup>
+  </ItemGroup>
 
+  <ItemGroup>
+    <None Include="README.md" Pack="true" PackagePath="\" />
+  </ItemGroup>
 </Project>

RAIC.Extensions.Configuration.EntityFrameworkCore.SqlServer/README.md

@@ -7,8 +7,8 @@ This library enhances `RAIC.Extensions.Configuration.EntityFrameworkCore` with s
 
 ## Goals
 1. No polling!
-1. Updates happen in background via worker service (`IHostedService`)
+1. Updates happen in background via a [hosted service](https://learn.microsoft.com/en-us/aspnet/core/fundamentals/host/hosted-services) implementation
-1. Only update settings which change rather than reloading all of them
+1. Only update settings which change rather than updating them all
 
 
 ## Requirements
@@ -17,13 +17,16 @@ This library enhances `RAIC.Extensions.Configuration.EntityFrameworkCore` with s
 ## Gotchas
 * Won't work with Azure SQL until Microsoft adds/enables Service Broker support
 * Setting values cannot be `null` (as signified by the `RequiredAttribute` on `ISetting.Value`)
+* Consider adding `ConnectRetryCount` and `ConnectRetryInterval` [parameters](https://learn.microsoft.com/en-us/dotnet/framework/data/adonet/whats-new#sqlclient-data-provider) to your connection string if not already present
 
 ## Known Issues
 * Not tested under load
+* Transient failure detection logic is not well tested given the challenges in reproducing these issues
 
 ## Configuration Options
-There is a single property which can be configured (cf. the `SqlServerNotificationConfigurationReloaderOptions` POCO)
+There are two properties which can be configured (cf. the `SqlServerNotificationConfigurationReloaderOptions` POCO)
 1. `ConnectionString` - the full connection string for the SQL Server instance
+1. `TransientErrors` - the list of `SqlError.Number` values that will be treated as transient if present in a thrown `SqlException`'s `Errors` collection while listening for or processing notifications (ie. reconnection will be attempted if any are present)
 
 ## Setup
 For `SqlServerNotificationConfigurationReloader` to work it requires Change Tracking to be enable on the `Settings` table (and therefore also on the database itself)
@@ -37,7 +40,7 @@ ALTER TABLE dbo.Settings
 ENABLE CHANGE_TRACKING;
 ```
 
-Reccommend adding your SQL to the migration which adds the `Settings` table/view (or a new migration if that table/view already exists).
+Recommend adding your SQL to the migration which adds the `Settings` table/view (or a new migration if that table/view already exists).
 
 ## Usage Example
 
@@ -57,9 +60,11 @@ public record Setting : ISetting
     public required string Value { get; set; }
 }
 
-public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options), ISettingsDbContext<DbSet<Setting>,Setting>
+public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options), ISettingsDbContext<DbSet<Setting>>, ISettingsDbContextFactory<MyDbContext>
 {
     public DbSet<Setting> Settings { get; set; }
+
+    public static MyDbContext Create(DbContextOptions<MyDbContext> options) => new(options);
 }
 
 
@@ -70,7 +75,7 @@ builder.Configuration.AddJsonFile("appsettings.json")
                      ...
                      .AddUserSecrets<Program>(); // or wherever your connection string lives
 
-builder.Configuration.AddDbSet<MyDbContext, Setting>(dbContextOptions => dbContextOptions.UseSqlServer(builder.Configuration.GetConnectionString("Default")));
+builder.Configuration.AddDbContext<MyDbContext>(dbContextOptions => dbContextOptions.UseSqlServer(builder.Configuration.GetConnectionString("Default")));
 
 ...
 // Add the SqlServerNotificationConfigurationReloader background service and supporting services to obtain setting reloading functionalty

RAIC.Extensions.Configuration.EntityFrameworkCore.SqlServer/SqlServerNotificationConfigurationReloader.cs

@@ -1,7 +1,5 @@
 using System.ComponentModel.DataAnnotations;
 using System.Data;
-using System.Runtime.CompilerServices;
-using System.Threading.Tasks;
 using Microsoft.Data.SqlClient;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Logging;
@@ -14,11 +12,14 @@ public class SqlServerNotificationConfigurationReloaderOptions // must be public
 {
     [Required]
     public required string ConnectionString { get; set; }
+
+    [Required]
+    public required HashSet<int> TransientErrors { get; set; } = [2, 53, 121, 10060, 11001];
 }
 
 
 internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting> : Microsoft.Extensions.Hosting.BackgroundService
-    where TDbContext : DbContext, ISettingsDbContext<DbSet<TSetting>, TSetting>
+    where TDbContext : DbContext, ISettingsDbContext<IQueryable<TSetting>>
     where TSetting : class, ISetting
 {
     private static string? _changesQueryTemplate;
@@ -42,35 +43,50 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
 
     protected override async Task ExecuteAsync(CancellationToken stoppingToken)
     {
-        var settingsQuery = await Initialise(stoppingToken);
 
-        do
+        try
         {
+            var settingsQuery = await Initialise(stoppingToken);
+
             do
             {
-                var (taskCompletionSource, cancelTokenRegistration) = await ListenForNotifications(settingsQuery, stoppingToken);
+                try
-                using (cancelTokenRegistration)
                 {
-                    var lastVersion = await GetChangeTrackingVersion(stoppingToken);
+                    do
-
-                    try
                     {
-                        await taskCompletionSource.Task;
+                        var notificationCompletion = await ListenForNotifications(settingsQuery, stoppingToken);
+                        using var tcsCancelRegistration = stoppingToken.Register(() => notificationCompletion.TrySetCanceled());
+
+                        var lastVersion = await GetChangeTrackingVersion(stoppingToken);
+
+                        await notificationCompletion.Task;
                         UpdateConfiguration(lastVersion);
                     }
-                    catch (Exception e) when (e is not TaskCanceledException)
+                    while (true); // each notification is one-and-done, so must keep re-regesitering for notifications indefinitely
-                    {
+                }
-                        _logger?.LogWarning(e, "Exception while listening for notifications on query '{query}'", settingsQuery);
+                catch (SqlException e) when (e.InnerException is SqlException inner && _options.TransientErrors.Overlaps(inner.Errors.OfType<SqlError>().Select(e => e.Number)))
-                        break;
+                {
-                    }
+                    _logger?.LogWarning(e, "Transient exception during notification setup process or the processing of notifications");
+                }
+                catch (SqlNotificationException e) // only ever thown while waiting for notification task to complete, must (?) be dropped connection of some sort
+                {
+                    _logger?.LogWarning(e, "Transient exception while listening for notifications");
+                }
+                catch (Exception e) when (e is not OperationCanceledException)
+                {
+                    _logger?.LogError(e, "Exception while setting up, listening for or processing notifications");
+                    throw;
                 }
             }
-            while (true); // each notification is one-and-done, so must keep re-regesitering indefinitely
+            while (await TryReconnect(stoppingToken));
-        }
-        while (await ReconnectOnDependencyException(stoppingToken));
 
-        _logger?.LogWarning("Giving up listening for notifications on query '{query}' because reconnection failed. Configuration updates from database will no longer occur", settingsQuery);
+            _logger?.LogWarning("Giving up listening for notifications on query '{query}' because reconnection failed. Configuration updates from database will no longer occur", settingsQuery);
-        SqlDependency.Stop(_options.ConnectionString);
+            SqlDependency.Stop(_options.ConnectionString);
+        }
+        catch (OperationCanceledException e)
+        {
+            _logger?.LogInformation(e, "Exiting due to signal from stopping token");
+        }
     }
 
 
@@ -90,7 +106,7 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
 
         var settingsQuery = _dbContext.Settings.ToQueryString();
 
-        _logger?.LogInformation("Listening for notifications on query '{query}'", settingsQuery);
+        _logger?.LogInformation(@"Query upon which notifications will be listened for: ""{query}""", settingsQuery);
 
         await openTask;
 
@@ -98,8 +114,10 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
     }
 
 
-    private async Task<(TaskCompletionSource, CancellationTokenRegistration)> ListenForNotifications(string settingsQuery, CancellationToken stoppingToken)
+    private async Task<TaskCompletionSource> ListenForNotifications(string settingsQuery, CancellationToken stoppingToken)
     {
+        // Can't reuse the command built here, as once it gets associated with a SqlDependency it can't be used with another,
+        // and SqlDependencies can't be used more than once either... hence there's no point "preparing" the command either
         using var command = new SqlCommand()
         {
             Connection = (SqlConnection)_dbContext.Database.GetDbConnection(),
@@ -110,22 +128,22 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
         var dependency = new SqlDependency(command);
         var tcs = new TaskCompletionSource();
         dependency.OnChange += OnChange;
-        var tcsCancelRegistration = stoppingToken.Register(() => tcs.TrySetCanceled());
 
         try
         {
             await command.ExecuteNonQueryAsync(stoppingToken);
         }
-        catch (Exception e) when (e is not TaskCanceledException)
+        catch (Exception e) when (e is not OperationCanceledException)
         {
             _logger?.LogError(e, "Exception while attempting to register query dependency");
             throw;
         }
 
-        return (tcs, tcsCancelRegistration);
+        return tcs;
 
         void OnChange(object sender, SqlNotificationEventArgs args)
         {
+            dependency.OnChange -= OnChange;
             switch (args.Info)
             {
                 case SqlNotificationInfo.Insert:
@@ -137,7 +155,7 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
                     return;
                 case SqlNotificationInfo.Error:
                     _logger?.LogWarning("SqlDependency '{info}' from {type}@{source}", args.Info, args.Type, args.Source);
-                    tcs.TrySetException(new Exception($"SqlDependency {args.Info} from {args.Type}@{args.Source}"));
+                    tcs.TrySetException(new SqlNotificationException($"SqlDependency {args.Info} from {args.Type}@{args.Source}"));
                     return;
                 default:
                     _logger?.LogWarning("Ignoring '{info}' from {type}@{source} received from SqlDependency", args.Info, args.Type, args.Source);
@@ -150,7 +168,7 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
     private async Task<long> GetChangeTrackingVersion(CancellationToken stoppingToken)
     {
         var query = "SELECT CHANGE_TRACKING_CURRENT_VERSION() as value";
-        return await _dbContext.Database.SqlQueryRaw<long>(query).FirstOrDefaultAsync(stoppingToken);
+        return await _dbContext.Database.SqlQueryRaw<long>(query).SingleAsync(stoppingToken);
     }
 
 
@@ -200,19 +218,15 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
     }
 
 
-    private async Task<bool> ReconnectOnDependencyException(CancellationToken stoppingToken)
+    private async Task<bool> TryReconnect(CancellationToken stoppingToken)
     {
-        // explicitly close connection to force subsequent OpenConnectionAsync() to actually try to open the connection instead of it possibly being a no-op
+        // Unlike the postgres version of this there's no retry logic here - SqlClient does its own retries internally so it is not needed (?)
-        await _dbContext.Database.CloseConnectionAsync();
+        if (await _dbContext.Database.CanConnectAsync(stoppingToken))
-        try
         {
             await _dbContext.Database.OpenConnectionAsync(stoppingToken);
             return true;
         }
-        catch (Exception e)
+
-        {
-            _logger?.LogWarning(e, "Exception while attempting to reconnect to database. Configuration updates from database will no longer occur");
-        }
         return false;
     }
 
@@ -265,4 +279,15 @@ internal class SqlServerNotificationConfigurationReloader<TDbContext, TSetting>
         base.Dispose();
         _onChangeHandler?.Dispose();
     }
+
+    private class SqlNotificationException : Exception
+    {
+        public SqlNotificationException(string? message) : base(message)
+        {
+        }
+
+        public SqlNotificationException(string? message, Exception? innerException) : base(message, innerException)
+        {
+        }
+    }
 }

RAIC.Extensions.Configuration.EntityFrameworkCore/EntityFrameworkCoreDbSetConfigurationProvider.cs

@@ -1,5 +1,4 @@
 using System.Linq;
-using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Configuration;
 
 namespace RAIC.Extensions.Configuration.EntityFrameworkCore;
@@ -7,26 +6,25 @@ namespace RAIC.Extensions.Configuration.EntityFrameworkCore;
 
 internal interface IEntityFrameworkCoreDbSetConfigurationProvider : IConfigurationProvider
 {
-    void OnReload();
+    internal void OnReload();
 
-    bool Remove(string key);
+    internal bool Remove(string key);
 }
 
 
-internal class EntityFrameworkCoreDbSetConfigurationProvider<TDbContext, TSetting> : ConfigurationProvider, IEntityFrameworkCoreDbSetConfigurationProvider
+internal class EntityFrameworkCoreDbSetConfigurationProvider<TDbContext> : ConfigurationProvider, IEntityFrameworkCoreDbSetConfigurationProvider
-    where TDbContext : DbContext, ISettingsDbContext<DbSet<TSetting>, TSetting>
+    where TDbContext : ISettingsDbContext<IQueryable<ISetting>>
-    where TSetting : class, ISetting
 {
-    private readonly IEntityFrameworkCoreDbSetConfigurationSource<TDbContext> _configurationSource;
+    private readonly EntityFrameworkCoreDbSetConfigurationSource<TDbContext> _configurationSource;
 
-    internal EntityFrameworkCoreDbSetConfigurationProvider(IEntityFrameworkCoreDbSetConfigurationSource<TDbContext> configurationSource) : base()
+    internal EntityFrameworkCoreDbSetConfigurationProvider(EntityFrameworkCoreDbSetConfigurationSource<TDbContext> configurationSource) : base()
     {
         _configurationSource = configurationSource;
     }
 
     public override void Load()
     {
-        using var dbContext = _configurationSource.DbContextFactory!.CreateDbContext();
+        using var dbContext = _configurationSource.DbContextFactory();
         Data = dbContext.Settings.ToDictionary(s => s.Key, s => (string?)s.Value);
     }
 
@@ -35,19 +33,14 @@ internal class EntityFrameworkCoreDbSetConfigurationProvider<TDbContext, TSettin
     public new void OnReload() => base.OnReload();
 }
 
-internal interface IEntityFrameworkCoreDbSetConfigurationSource<TDbContext> where TDbContext : DbContext
-{
-    internal IDbContextFactory<TDbContext> DbContextFactory { get; }
-}
 
-internal class EntityFrameworkCoreDbSetConfigurationSource<TDbContext, TSetting> : IConfigurationSource, IEntityFrameworkCoreDbSetConfigurationSource<TDbContext>
+internal class EntityFrameworkCoreDbSetConfigurationSource<TDbContext> : IConfigurationSource
-    where TDbContext : DbContext, ISettingsDbContext<DbSet<TSetting>, TSetting>
+    where TDbContext : ISettingsDbContext<IQueryable<ISetting>>
-    where TSetting : class, ISetting
 {
-    public required IDbContextFactory<TDbContext> DbContextFactory { get; init; }
+    public required System.Func<TDbContext> DbContextFactory { get; init; }
 
     public IConfigurationProvider Build(IConfigurationBuilder builder)
     {
-        return new EntityFrameworkCoreDbSetConfigurationProvider<TDbContext, TSetting>(this);
+        return new EntityFrameworkCoreDbSetConfigurationProvider<TDbContext>(this);
     }
 }

RAIC.Extensions.Configuration.EntityFrameworkCore/Extensions/ConfigurationBuilderExtensions.cs

@@ -1,5 +1,4 @@
 using Microsoft.EntityFrameworkCore;
-using Microsoft.EntityFrameworkCore.Infrastructure;
 using Microsoft.Extensions.Configuration;
 
 namespace RAIC.Extensions.Configuration.EntityFrameworkCore.Extensions;
@@ -11,8 +10,7 @@ public static class ConfigurationBuilderExtensions
     /// <summary>
     /// Adds a <see cref="DbSet{}"/> off <typeparamref name="TDbContext"/> as a configuration provider to the <see cref="IConfigurationBuilder"/>.
     /// </summary>
-    /// <typeparam name="TDbContext">Type of the <see cref="DbContext"/> which implements <see cref="ISettingsDbContext{,}"/></typeparam>
+    /// <typeparam name="TDbContext">Type of the <see cref="DbContext"/> which implements both <see cref="ISettingsDbContext{}"/> and <see cref="ISettingsDbContextFactory{}"/></typeparam>
-    /// <typeparam name="TSetting">Concrete type which implements <see cref="ISetting"/></typeparam>
     /// <param name="optionsTransformer">
     /// a <see cref="DbContextOptionsTransformer{}"/> which configures your <see cref="DbContextOptions{}"/>. eg.
     /// <code>
@@ -20,14 +18,13 @@ public static class ConfigurationBuilderExtensions
     /// </code>
     /// </param>
     /// <returns>The <see cref="IConfigurationBuilder"/></returns>
-    public static IConfigurationBuilder AddDbSet<TDbContext, TSetting>(this IConfigurationBuilder builder, DbContextOptionsTransformer<TDbContext> optionsTransformer)
+    public static IConfigurationBuilder AddDbContext<TDbContext>(this IConfigurationBuilder builder, DbContextOptionsTransformer<TDbContext> optionsTransformer)
-        where TDbContext : DbContext, ISettingsDbContext<DbSet<TSetting>, TSetting>
+        where TDbContext : DbContext, ISettingsDbContext<System.Linq.IQueryable<ISetting>>, ISettingsDbContextFactory<TDbContext>
-        where TSetting : class, ISetting
     {
-        // DEBT: Find way to create non-pooled DbContextFactory since this is only a short lived usage
+        var options = optionsTransformer(new DbContextOptionsBuilder<TDbContext>()).Options;
-        var configurationSource = new EntityFrameworkCoreDbSetConfigurationSource<TDbContext, TSetting>()
+        var configurationSource = new EntityFrameworkCoreDbSetConfigurationSource<TDbContext>()
         {
-            DbContextFactory = new PooledDbContextFactory<TDbContext>(optionsTransformer(new DbContextOptionsBuilder<TDbContext>()).Options, poolSize: 1)
+            DbContextFactory = () => TDbContext.Create(options)
         };
 
         return builder.Add(configurationSource);

RAIC.Extensions.Configuration.EntityFrameworkCore/ISettingsDbContext.cs

@@ -1,14 +1,18 @@
-using System;
+using System.ComponentModel.DataAnnotations;
-using System.ComponentModel.DataAnnotations;
 using Microsoft.EntityFrameworkCore;
 
 namespace RAIC.Extensions.Configuration.EntityFrameworkCore;
 
-public interface ISettingsDbContext<out TSettingDbSet, out TSetting> : IDisposable
+public interface ISettingsDbContext<out TSettings> : System.IDisposable
-    where TSettingDbSet : DbSet<TSetting>
+    where TSettings : System.Linq.IQueryable<ISetting>
-    where TSetting : class, ISetting
 {
-    TSettingDbSet Settings { get; }
+    TSettings Settings { get; }
+}
+
+public interface ISettingsDbContextFactory<TDbContext>
+    where TDbContext : DbContext
+{
+    static abstract TDbContext Create(DbContextOptions<TDbContext> options);
 }
 
 

RAIC.Extensions.Configuration.EntityFrameworkCore/RAIC.Extensions.Configuration.EntityFrameworkCore.csproj

@@ -5,6 +5,17 @@
 	<LangVersion>latest</LangVersion>
 	<Nullable>enable</Nullable>
   </PropertyGroup>
+	
+  <PropertyGroup>
+    <PackageId>RAIC.Extensions.Configuration.EntityFrameworkCore</PackageId>
+    <Version>0.1.1</Version>
+    <Authors>Rhys Ickeringill</Authors>
+    <Description>Entity Framework Core based configuration provider for Microsoft.Extensions.Configuration</Description>
+    <PackageTags>configuration;entityframeworkcore</PackageTags>
+    <RepositoryUrl>https://git.raickeringill.id.au/ickers/Extensions.Configuration.EntityFrameworkCore</RepositoryUrl>
+	<PackageLicenseExpression>MIT</PackageLicenseExpression>
+	<PackageReadmeFile>README.md</PackageReadmeFile>
+  </PropertyGroup>
 
   <ItemGroup>
 	<InternalsVisibleTo Include="RAIC.Extensions.Configuration.EntityFrameworkCore.PostgreSQL" />
@@ -16,4 +27,8 @@
     <PackageReference Include="Microsoft.Extensions.Configuration" Version="[8.0, 11.0)" />
   </ItemGroup>
 
+  <ItemGroup>
+    <None Include="README.md" Pack="true" PackagePath="\" />
+  </ItemGroup>
+	
 </Project>

RAIC.Extensions.Configuration.EntityFrameworkCore/README.md

@@ -33,19 +33,22 @@ public record Setting : ISetting
     public required string Value { get; set; }
 }
 
-public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options), ISettingsDbContext<DbSet<Setting>, Setting>
+public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options), ISettingsDbContext<DbSet<Setting>>, ISettingsDbContextFactory<MyDbContext>
 {
     public DbSet<Setting> Settings { get; set; }
+
+    public static MyDbContext Create(DbContextOptions<MyDbContext> options) => new(options);
 }
 
 var builder =  Host.CreateApplicationBuilder(args) // or  WebApplication.CreateBuilder(args); 
 
 // build an initial configuration
 builder.Configuration.AddJsonFile("appsettings.json")
+                     ...
                      .AddUserSecrets<Program>(); // or whereever your connection string lives
 
-// obtain connection string from preliminary config so can initialise other settings from DbSet
+// obtain connection string from preliminary config so can initialise other settings from DbContext
-builder.Configuration.AddDbSet<MyDbContext, Setting>(dbContextOptions => dbContextOptions.UseNpgsql(builder.Configuration.GetConnectionString("Default")));
+builder.Configuration.AddDbContext<MyDbContext>(dbContextOptions => dbContextOptions.UseNpgsql(builder.Configuration.GetConnectionString("Default")));
 
 ...