fix: Add copyright notice, use file-scoped namespaces, avoid binary breaking change

Signed-off-by: Jon Abaunza <j.abaunza@lantek.com>

src/CloudNative.CloudEvents.Kafka/CloudNative.CloudEvents.Kafka.csproj

@@ -4,7 +4,7 @@
     <TargetFrameworks>netstandard2.0;netstandard2.1;net8.0</TargetFrameworks>
     <Description>Kafka extensions for CloudNative.CloudEvents</Description>
     <PackageTags>cncf;cloudnative;cloudevents;events;kafka</PackageTags>
-    <LangVersion>9.0</LangVersion>
+    <LangVersion>10.0</LangVersion>
     <Nullable>enable</Nullable>
   </PropertyGroup>
 

src/CloudNative.CloudEvents.Kafka/KafkaExtensions.cs

@@ -25,6 +25,7 @@ namespace CloudNative.CloudEvents.Kafka
         internal const string KafkaContentTypeAttributeName = "content-type";
         private const string SpecVersionKafkaHeader = KafkaHeaderPrefix + "specversion";
 
+
         /// <summary>
         /// Indicates whether this message holds a single CloudEvent.
         /// </summary>
@@ -33,6 +34,17 @@ namespace CloudNative.CloudEvents.Kafka
         /// </remarks>
         /// <param name="message">The message to check for the presence of a CloudEvent. Must not be null.</param>
         /// <returns>true, if the request is a CloudEvent</returns>
+        public static bool IsCloudEvent(this Message<string?, byte[]> message) => IsCloudEvent<string?>(message);
+
+        /// <summary>
+        /// Indicates whether this message holds a single CloudEvent.
+        /// </summary>
+        /// <remarks>
+        /// This method returns false for batch requests, as they need to be parsed differently.
+        /// </remarks>
+        /// <param name="message">The message to check for the presence of a CloudEvent. Must not be null.</param>
+        /// <typeparam name="TKey">The type of key of the Kafka message.</typeparam>
+        /// <returns>true, if the request is a CloudEvent</returns>
         public static bool IsCloudEvent<TKey>(this Message<TKey, byte[]> message) =>
             GetHeaderValue(message, SpecVersionKafkaHeader) is object ||
             MimeUtilities.IsCloudEventsContentType(GetHeaderValue(message, KafkaContentTypeAttributeName));

src/CloudNative.CloudEvents.Kafka/PartitionKeyAdapters/BinaryGuidPartitionKeyAdapter.cs

@@ -1,12 +1,16 @@
+// Copyright (c) Cloud Native Foundation.
+// Licensed under the Apache 2.0 license.
+// See LICENSE file in the project root for full license information.
+
 using System;
 
-namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
+namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters;
+
+/// <summary>
+/// Partion Key Adapter that converts to and from Guids in binary representation.
+/// </summary>
+public class BinaryGuidPartitionKeyAdapter : IPartitionKeyAdapter<byte[]?>
 {
-    /// <summary>
-    /// Partion Key Adapter that converts to and from Guids in binary representation.
-    /// </summary>
-    public class BinaryGuidPartitionKeyAdapter : IPartitionKeyAdapter<byte[]?>
-    {
     /// <inheritdoc/>
     public bool ConvertKeyToPartitionKeyAttributeValue(byte[]? keyValue, out string? attributeValue)
     {
@@ -32,5 +36,4 @@ namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
         keyValue = Guid.Parse(attributeValue).ToByteArray();
         return true;
     }
-    }
 }

src/CloudNative.CloudEvents.Kafka/PartitionKeyAdapters/IPartitionKeyAdapter.cs

@@ -1,12 +1,16 @@
-namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
+// Copyright (c) Cloud Native Foundation.
+// Licensed under the Apache 2.0 license.
+// See LICENSE file in the project root for full license information.
+
+namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters;
+
+/// <summary>
+/// Defines the methods of the adapters responsible for transforming from cloud event
+/// PartitionKey Attribute to Kafka Message Key.
+/// </summary>
+/// <typeparam name="TKey">The type of Kafka Message Key.</typeparam>
+public interface IPartitionKeyAdapter<TKey>
 {
-    /// <summary>
-    /// Defines the methods of the adapters responsible for transforming from cloud event
-    /// PartitionKey Attribute to Kafka Message Key.
-    /// </summary>
-    /// <typeparam name="TKey"></typeparam>
-    public interface IPartitionKeyAdapter<TKey>
-    {
     /// <summary>
     /// Converts a Message Key to PartionKey Attribute Value.
     /// </summary>
@@ -22,5 +26,4 @@ namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
     /// <param name="keyValue">The transformed key value (output)</param>
     /// <returns>Whether the key should be set.</returns>
     bool ConvertPartitionKeyAttributeValueToKey(string? attributeValue, out TKey? keyValue);
-    }
 }

src/CloudNative.CloudEvents.Kafka/PartitionKeyAdapters/NullPartitionKeyAdapter.cs

@@ -1,11 +1,15 @@
-namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
+// Copyright (c) Cloud Native Foundation.
+// Licensed under the Apache 2.0 license.
+// See LICENSE file in the project root for full license information.
+
+namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters;
+
+/// <summary>
+/// Partion Key Adapter that skips handling the key.
+/// </summary>
+/// <typeparam name="TKey">The type of Kafka Message Key.</typeparam>
+public class NullPartitionKeyAdapter<TKey> : IPartitionKeyAdapter<TKey>
 {
-    /// <summary>
-    /// Partion Key Adapter that skips handling the key.
-    /// </summary>
-    /// <typeparam name="TKey">The type of Kafka Message Key</typeparam>
-    public class NullPartitionKeyAdapter<TKey> : IPartitionKeyAdapter<TKey>
-    {
     /// <inheritdoc/>
     public bool ConvertKeyToPartitionKeyAttributeValue(TKey keyValue, out string? attributeValue)
     {
@@ -19,5 +23,4 @@ namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
         keyValue = default;
         return false;
     }
-    }
 }

src/CloudNative.CloudEvents.Kafka/PartitionKeyAdapters/StringPartitionKeyAdapter.cs

@@ -1,10 +1,14 @@
-namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
+// Copyright (c) Cloud Native Foundation.
+// Licensed under the Apache 2.0 license.
+// See LICENSE file in the project root for full license information.
+
+namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters;
+
+/// <summary>
+/// Partion Key Adapter that skips handling the key.
+/// </summary>
+public class StringPartitionKeyAdapter : IPartitionKeyAdapter<string?>
 { 
-    /// <summary>
-    /// Partion Key Adapter that skips handling the key.
-    /// </summary>
-    public class StringPartitionKeyAdapter : IPartitionKeyAdapter<string?>
-    { 
     /// <inheritdoc/>
     public bool ConvertKeyToPartitionKeyAttributeValue(string? keyValue, out string? attributeValue)
     {
@@ -18,5 +22,4 @@ namespace CloudNative.CloudEvents.Kafka.PartitionKeyAdapters
         keyValue = attributeValue;
         return true;
     }
-    }
 }

test/CloudNative.CloudEvents.UnitTests/Kafka/KafkaTest.cs

@@ -140,7 +140,6 @@ namespace CloudNative.CloudEvents.Kafka.UnitTests
         public void KafkaNullKeyedStructuredMessageTest()
         {
             // It will test the serialization using Confluent's Confluent.Kafka.Null type for the key.
-            // As the default behavior without adapter is to skip the key it will work properly.
             var partitionKeyAdapter = new PartitionKeyAdapters.NullPartitionKeyAdapter<Confluent.Kafka.Null>();
             var jsonEventFormatter = new JsonEventFormatter();
             var cloudEvent = CreateTestCloudEvent();