refactor: move ExpectedRevision to StreamState. (#337)

Author: YoEight

samples/appending-events/Program.cs

@@ -102,7 +102,7 @@ await client.AppendToStreamAsync(
 static async Task AppendWithConcurrencyCheck(KurrentDBClient client) {
 	await client.AppendToStreamAsync(
 		"concurrency-stream",
-		StreamRevision.None,
+		StreamState.Any,
 		new[] { new EventData(Uuid.NewUuid(), "-", ReadOnlyMemory<byte>.Empty) }
 	);
 

samples/server-side-filtering/Program.cs

@@ -38,7 +38,7 @@
 
 	await client.AppendToStreamAsync(
 		Guid.NewGuid().ToString("N"),
-		StreamRevision.None,
+		StreamState.Any,
 		new List<EventData> { eventData }
 	);
 }

src/KurrentDB.Client/Core/Common/MetadataExtensions.cs

@@ -17,10 +17,10 @@ public static bool TryGetValue(this Metadata metadata, string key, out string? v
 		return false;
 	}
 
-	public static StreamRevision GetStreamRevision(this Metadata metadata, string key) =>
+	public static StreamState GetStreamState(this Metadata metadata, string key) =>
 		metadata.TryGetValue(key, out var s) && ulong.TryParse(s, out var value)
-			? new(value)
-			: StreamRevision.None;
+			? value
+			: StreamState.NoStream;
 
 	public static int GetIntValueOrDefault(this Metadata metadata, string key) =>
 		metadata.TryGetValue(key, out var s) && int.TryParse(s, out var value)

src/KurrentDB.Client/Core/Exceptions/WrongExpectedVersionException.cs

@@ -24,43 +24,26 @@ public class WrongExpectedVersionException : Exception {
 		/// <summary>
 		/// The current <see cref="StreamRevision" /> of the stream that the operation was attempted on.
 		/// </summary>
-		public StreamRevision ActualStreamRevision { get; }
+		public StreamState ActualStreamState { get; }
 
 		/// <summary>
 		/// If available, the expected version specified for the operation that failed.
 		/// </summary>
-		public StreamRevision ExpectedStreamRevision { get; }
+		public StreamState ExpectedStreamState { get; }
 
 		/// <summary>
 		/// Constructs a new instance of <see cref="WrongExpectedVersionException" /> with the expected and actual versions if available.
 		/// </summary>
-		public WrongExpectedVersionException(string streamName, StreamRevision expectedStreamRevision,
-			StreamRevision actualStreamRevision, Exception? exception = null, string? message = null) :
+		public WrongExpectedVersionException(string streamName, StreamState expectedStreamState,
+			StreamState actualStreamState, Exception? exception = null, string? message = null) :
 			base(
-				message ?? $"Append failed due to WrongExpectedVersion. Stream: {streamName}, Expected version: {expectedStreamRevision}, Actual version: {actualStreamRevision}",
+				message ?? $"Append failed due to WrongExpectedVersion. Stream: {streamName}, Expected version: {expectedStreamState}, Actual version: {actualStreamState}",
 				exception) {
 			StreamName = streamName;
-			ActualStreamRevision = actualStreamRevision;
-			ExpectedStreamRevision = expectedStreamRevision;
-			ExpectedVersion = expectedStreamRevision == StreamRevision.None ? new long?() : expectedStreamRevision.ToInt64();
-			ActualVersion = actualStreamRevision == StreamRevision.None ? new long?() : actualStreamRevision.ToInt64();
-		}
-
-		/// <summary>
-		/// Constructs a new instance of <see cref="WrongExpectedVersionException" /> with the expected and actual versions if available.
-		/// </summary>
-		/// <param name="streamName"></param>
-		/// <param name="expectedStreamState"></param>
-		/// <param name="actualStreamRevision"></param>
-		/// <param name="exception"></param>
-		public WrongExpectedVersionException(string streamName, StreamState expectedStreamState,
-			StreamRevision actualStreamRevision, Exception? exception = null) : base(
-			$"Append failed due to WrongExpectedVersion. Stream: {streamName}, Expected state: {expectedStreamState}, Actual version: {actualStreamRevision}",
-			exception) {
-			StreamName = streamName;
-			ActualStreamRevision = actualStreamRevision;
-			ActualVersion = actualStreamRevision == StreamRevision.None ? new long?() : actualStreamRevision.ToInt64();
-			ExpectedStreamRevision = StreamRevision.None;
+			ActualStreamState = actualStreamState;
+			ExpectedStreamState = expectedStreamState;
+			ExpectedVersion = expectedStreamState.ToInt64();
+			ActualVersion = actualStreamState.ToInt64();
 		}
 	}
 }

src/KurrentDB.Client/Core/StreamPosition.cs

@@ -30,9 +30,9 @@ public static StreamPosition FromInt64(long value) =>
 		/// </summary>
 		/// <param name="revision"></param>
 		/// <returns></returns>
-		public static StreamPosition FromStreamRevision(StreamRevision revision) => revision.ToUInt64() switch {
+		public static StreamPosition FromStreamRevision(ulong revision) => revision switch {
 			ulong.MaxValue => throw new ArgumentOutOfRangeException(nameof(revision)),
-			_ => new StreamPosition(revision.ToUInt64())
+			_ => new StreamPosition(revision)
 		};
 
 		/// <summary>

src/KurrentDB.Client/Core/StreamRevision.cs

@@ -20,23 +20,29 @@ namespace KurrentDB.Client {
 		/// </summary>
 		public static readonly StreamState StreamExists = new StreamState(Constants.StreamExists);
 
-		private readonly int _value;
+		public static StreamState StreamRevision(ulong value) => new StreamState((long)value);
+
+		private readonly long _value;
 
 		private static class Constants {
-			public const int NoStream = 1;
-			public const int Any = 2;
-			public const int StreamExists = 4;
+			public const int NoStream = -1;
+			public const int Any = -2;
+			public const int StreamExists = -4;
 		}
 
-		internal StreamState(int value) {
+		internal StreamState(long value) {
 			switch (value) {
 				case Constants.NoStream:
 				case Constants.Any:
 				case Constants.StreamExists:
 					_value = value;
 					return;
 				default:
-					throw new ArgumentOutOfRangeException(nameof(value));
+					if (value < 0)
+						throw new ArgumentOutOfRangeException(nameof(value));
+
+					_value = value;
+					return;
 			}
 		}
 
@@ -69,13 +75,11 @@ internal StreamState(int value) {
 		/// Converts the <see cref="StreamState"/> to a <see cref="long"/>. It is not meant to be used directly from your code.
 		/// </summary>
 		/// <returns></returns>
-		public long ToInt64() => -Convert.ToInt64(_value);
+		public long ToInt64() => _value;
 
-		/// <summary>
-		/// Converts the <see cref="StreamState"/> to an <see cref="int"/>. It is not meant to be used directly from your code.
-		/// </summary>
-		/// <returns></returns>
-		public static implicit operator int(StreamState streamState) => streamState._value;
+		public bool HasPosition => _value >= 0;
+
+		public static implicit operator StreamState(ulong value) => new StreamState((long)value);
 
 		/// <inheritdoc />
 		public override string ToString() => _value switch {

src/KurrentDB.Client/Core/StreamState.cs

@@ -13,7 +13,7 @@
 		<PackageReference Include="Microsoft.Extensions.Logging" Version="9.0.0"/>
 		<PackageReference Include="System.Diagnostics.DiagnosticSource" Version="9.0.0"/>
 		<PackageReference Include="System.Linq.Async" Version="6.0.1"/>
-	  <PackageReference Include="OpenTelemetry.Api" Version="1.10.0" />
+	  <PackageReference Include="OpenTelemetry.Api" Version="1.11.2" />
 
 		<PackageReference Include="Grpc.Tools" Version="2.68.1">
 			<PrivateAssets>all</PrivateAssets>