Engine: Support parsing the weak ETag representation

Author: kennethmyhra

src/Spark.Engine.Test/Extensions/HttpRequestFhirExtensionsTests.cs

@@ -9,6 +9,8 @@
 using System;
 using System.Net.Http;
 using Hl7.Fhir.Rest;
+using Microsoft.AspNetCore.Http;
+using Microsoft.Extensions.Primitives;
 using Spark.Engine.Utility;
 using System.Linq;
 using Xunit;
@@ -17,6 +19,78 @@ namespace Spark.Engine.Test.Extensions;
 
 public class HttpRequestFhirExtensionsTests
 {
+    [Theory]
+    [InlineData("W/\"1\"", "1")]
+    [InlineData("W/\"123\"", "123")]
+    [InlineData("\"1\"", "1")]
+    [InlineData("\"123\"", "123")]
+    public void IfMatchVersionId_ShouldExtractVersionFromETag(string headerValue, string expectedVersionId)
+    {
+        var context = new DefaultHttpContext();
+        context.Request.Headers.Add("If-Match", new StringValues(headerValue));
+
+        string actualVersionId = context.Request.IfMatchVersionId();
+
+        Assert.Equal(expectedVersionId, actualVersionId);
+    }
+
+    [Fact]
+    public void IfMatchVersionId_WithNoHeader_ShouldReturnNull()
+    {
+        var context = new DefaultHttpContext();
+
+        string actualVersionId = context.Request.IfMatchVersionId();
+
+        Assert.Null(actualVersionId);
+    }
+
+    [Fact]
+    public void IfMatchVersionId_WithEmptyHeaders_ShouldReturnNull()
+    {
+        var context = new DefaultHttpContext();
+        context.Request.Headers.Add("If-Match", "");
+
+        string actualVersionId = context.Request.IfMatchVersionId();
+
+        Assert.Null(actualVersionId);
+    }
+
+    [Theory]
+    [InlineData("W/\"1\"", "1")]
+    [InlineData("W/\"123\"", "123")]
+    [InlineData("\"1\"", "1")]
+    [InlineData("\"123\"", "123")]
+    public void HttpRequestMessage_IfMatchVersionId_ShouldExtractVersionFromETag(string headerValue, string expectedVersionId)
+    {
+        var request = new HttpRequestMessage();
+        request.Headers.Add("If-Match", headerValue);
+
+        string actualVersionId = request.IfMatchVersionId();
+
+        Assert.Equal(expectedVersionId, actualVersionId);
+    }
+
+    [Fact]
+    public void HttpRequestMessage_IfMatchVersionId_WithNoHeader_ShouldReturnNull()
+    {
+        var request = new HttpRequestMessage();
+
+        string actualVersionId = request.IfMatchVersionId();
+
+        Assert.Null(actualVersionId);
+    }
+
+    [Fact]
+    public void HttpRequestMessage_IfMatchVersionId_WithEmptyHeaders_ShouldReturnNull()
+    {
+        var request = new HttpRequestMessage();
+        request.Headers.Add("If-Match", "");
+
+        string actualVersionId = request.IfMatchVersionId();
+
+        Assert.Null(actualVersionId);
+    }
+
     [Fact]
     public void TestGetDateParameter()
     {
@@ -62,4 +136,4 @@ public void TupledParameters_MustPreserveComma()
 
         Assert.NotNull(parameters.FirstOrDefault(p => p.Equals(Tuple.Create("arg", "A,B"))));
     }
-}
+}

src/Spark.Engine/Extensions/HttpRequestFhirExtensions.cs

@@ -23,25 +23,14 @@
 using Microsoft.AspNetCore.Http.Headers;
 using Microsoft.AspNetCore.Http;
 using Microsoft.Extensions.Primitives;
+using Microsoft.Net.Http.Headers;
 #endif
 
 [assembly: InternalsVisibleTo("Spark.Engine.Test")]
 namespace Spark.Engine.Extensions;
 
 public static class HttpRequestFhirExtensions
 {
-    private static string WithoutQuotes(string s)
-    {
-        if (string.IsNullOrEmpty(s))
-        {
-            return null;
-        }
-        else
-        {
-            return s.Trim('"');
-        }
-    }
-
 #if NETSTANDARD2_0 || NET6_0
         public static int GetPagingOffsetParameter(this HttpRequest request)
         {
@@ -77,12 +66,8 @@ internal static IEnumerable<string> IfNoneMatch(this HttpRequest request)
 
         public static string IfMatchVersionId(this HttpRequest request)
         {
-            if (request.Headers.Count == 0) return null;
-
-            if (!request.Headers.TryGetValue("If-Match", out StringValues value)) return null;
-            var tag = value.FirstOrDefault();
-            if (tag == null) return null;
-            return WithoutQuotes(tag);
+            EntityTagHeaderValue etag = request.GetTypedHeaders().IfMatch?.FirstOrDefault();
+            return etag?.Tag.Value?.Trim('"');
         }
 
         internal static SummaryType RequestSummary(this HttpRequest request)
@@ -309,22 +294,8 @@ private static bool PreferRepresentation(this HttpRequestMessage request)
 
     public static string IfMatchVersionId(this HttpRequestMessage request)
     {
-        if (request.Headers.Count() > 0)
-        {
-            var tag = request.Headers.IfMatch.FirstOrDefault();
-            if (tag != null)
-            {
-                return WithoutQuotes(tag.Tag);
-            }
-            else
-            {
-                return null;
-            }
-        }
-        else
-        {
-            return null;
-        }
+        var etag = request.Headers.IfMatch.FirstOrDefault();
+        return etag?.Tag?.Trim('"');
     }
 
     private static SummaryType GetSummary(string summary)

src/Spark.Web/Controllers/FhirController.cs

@@ -55,7 +55,7 @@ public async Task<FhirResponse> VRead(string type, string id, string vid)
     [HttpPut("{type}/{id?}")]
     public async Task<ActionResult<FhirResponse>> Update(string type, Resource resource, string id = null)
     {
-        string versionId = Request.GetTypedHeaders().IfMatch?.FirstOrDefault()?.Tag.Buffer;
+        string versionId = Request.IfMatchVersionId();
         Key key = Key.Create(type, id, versionId);
         if (key.HasResourceId())
         {
@@ -243,4 +243,4 @@ public async Task<FhirResponse> Document(string id)
         Key key = Key.Create("Composition", id);
         return await _fhirService.DocumentAsync(key).ConfigureAwait(false);
     }
-}
+}