Adds support for HEAD requests

Author: Bart Koelman

src/JsonApiDotNetCore/Controllers/JsonApiController.cs

@@ -42,27 +42,31 @@ protected JsonApiController(IJsonApiOptions options, ILoggerFactory loggerFactor
 
         /// <inheritdoc />
         [HttpGet]
+        [HttpHead]
         public override async Task<IActionResult> GetAsync(CancellationToken cancellationToken)
         {
             return await base.GetAsync(cancellationToken);
         }
 
         /// <inheritdoc />
         [HttpGet("{id}")]
+        [HttpHead("{id}")]
         public override async Task<IActionResult> GetAsync(TId id, CancellationToken cancellationToken)
         {
             return await base.GetAsync(id, cancellationToken);
         }
 
         /// <inheritdoc />
         [HttpGet("{id}/{relationshipName}")]
+        [HttpHead("{id}/{relationshipName}")]
         public override async Task<IActionResult> GetSecondaryAsync(TId id, string relationshipName, CancellationToken cancellationToken)
         {
             return await base.GetSecondaryAsync(id, relationshipName, cancellationToken);
         }
 
         /// <inheritdoc />
         [HttpGet("{id}/relationships/{relationshipName}")]
+        [HttpHead("{id}/relationships/{relationshipName}")]
         public override async Task<IActionResult> GetRelationshipAsync(TId id, string relationshipName, CancellationToken cancellationToken)
         {
             return await base.GetRelationshipAsync(id, relationshipName, cancellationToken);

src/JsonApiDotNetCore/Middleware/JsonApiMiddleware.cs

@@ -4,7 +4,6 @@
 using System.Linq;
 using System.Net;
 using System.Net.Http;
-using System.Net.Http.Headers;
 using System.Text;
 using System.Threading.Tasks;
 using JetBrains.Annotations;
@@ -16,6 +15,7 @@
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Controllers;
 using Microsoft.AspNetCore.Routing;
+using Microsoft.Net.Http.Headers;
 using Newtonsoft.Json;
 
 namespace JsonApiDotNetCore.Middleware
@@ -46,7 +46,6 @@ public async Task InvokeAsync(HttpContext httpContext, IControllerResourceMappin
             ArgumentGuard.NotNull(resourceContextProvider, nameof(resourceContextProvider));
 
             RouteValueDictionary routeValues = httpContext.GetRouteData().Values;
-
             ResourceContext primaryResourceContext = CreatePrimaryResourceContext(httpContext, controllerResourceMapping, resourceContextProvider);
 
             if (primaryResourceContext != null)
@@ -130,7 +129,7 @@ private static async Task<bool> ValidateAcceptHeaderAsync(MediaTypeHeaderValue a
 
             foreach (string acceptHeader in acceptHeaders)
             {
-                if (MediaTypeWithQualityHeaderValue.TryParse(acceptHeader, out MediaTypeWithQualityHeaderValue headerValue))
+                if (MediaTypeHeaderValue.TryParse(acceptHeader, out MediaTypeHeaderValue headerValue))
                 {
                     headerValue.Quality = null;
 
@@ -189,7 +188,7 @@ private static async Task FlushResponseAsync(HttpResponse httpResponse, JsonSeri
         private static void SetupResourceRequest(JsonApiRequest request, ResourceContext primaryResourceContext, RouteValueDictionary routeValues,
             IJsonApiOptions options, IResourceContextProvider resourceContextProvider, HttpRequest httpRequest)
         {
-            request.IsReadOnly = httpRequest.Method == HttpMethod.Get.Method;
+            request.IsReadOnly = httpRequest.Method == HttpMethod.Get.Method || httpRequest.Method == HttpMethod.Head.Method;
             request.Kind = EndpointKind.Primary;
             request.PrimaryResource = primaryResourceContext;
             request.PrimaryId = GetPrimaryRequestId(routeValues);

src/JsonApiDotNetCore/Serialization/JsonApiWriter.cs

@@ -63,8 +63,15 @@ public async Task WriteAsync(OutputFormatterWriteContext context)
                 response.StatusCode = (int)errorDocument.GetErrorStatusCode();
             }
 
+            if (context.HttpContext.Request.Method == HttpMethod.Head.Method)
+            {
+                responseContent = string.Empty;
+            }
+
             string url = context.HttpContext.Request.GetEncodedUrl();
-            _traceWriter.LogMessage(() => $"Sending {response.StatusCode} response for request at '{url}' with body: <<{responseContent}>>");
+
+            _traceWriter.LogMessage(() =>
+                $"Sending {response.StatusCode} response for {context.HttpContext.Request.Method} request at '{url}' with body: <<{responseContent}>>");
 
             await writer.WriteAsync(responseContent);
             await writer.FlushAsync();
@@ -96,6 +103,11 @@ private string SerializeResponse(object contextObject, HttpStatusCode statusCode
             return _serializer.Serialize(contextObjectWrapped);
         }
 
+        private bool IsSuccessStatusCode(HttpStatusCode statusCode)
+        {
+            return new HttpResponseMessage(statusCode).IsSuccessStatusCode;
+        }
+
         private static object WrapErrors(object contextObject)
         {
             if (contextObject is IEnumerable<Error> errors)
@@ -110,10 +122,5 @@ private static object WrapErrors(object contextObject)
 
             return contextObject;
         }
-
-        private bool IsSuccessStatusCode(HttpStatusCode statusCode)
-        {
-            return new HttpResponseMessage(statusCode).IsSuccessStatusCode;
-        }
     }
 }

test/JsonApiDotNetCoreExampleTests/IntegrationTests/Logging/LoggingTests.cs

@@ -99,7 +99,7 @@ public async Task Logs_response_body_at_Trace_level()
             loggerFactory.Logger.Messages.Should().NotBeEmpty();
 
             loggerFactory.Logger.Messages.Should().ContainSingle(message => message.LogLevel == LogLevel.Trace &&
-                message.Text.StartsWith("Sending 200 response for request at 'http://localhost/auditEntries' with body: <<", StringComparison.Ordinal));
+                message.Text.StartsWith("Sending 200 response for GET request at 'http://localhost/auditEntries' with body: <<", StringComparison.Ordinal));
         }
 
         [Fact]

test/JsonApiDotNetCoreExampleTests/IntegrationTests/Serialization/SerializationTests.cs

@@ -39,6 +39,44 @@ public SerializationTests(ExampleIntegrationTestContext<TestableStartup<Serializ
             options.AllowClientGeneratedIds = true;
         }
 
+        [Fact]
+        public async Task Returns_no_body_for_successful_HEAD_request()
+        {
+            // Arrange
+            Meeting meeting = _fakers.Meeting.Generate();
+
+            await _testContext.RunOnDatabaseAsync(async dbContext =>
+            {
+                dbContext.Meetings.Add(meeting);
+                await dbContext.SaveChangesAsync();
+            });
+
+            string route = "/meetings/" + meeting.StringId;
+
+            // Act
+            (HttpResponseMessage httpResponse, string responseDocument) = await _testContext.ExecuteHeadAsync<string>(route);
+
+            // Assert
+            httpResponse.Should().HaveStatusCode(HttpStatusCode.OK);
+
+            responseDocument.Should().BeEmpty();
+        }
+
+        [Fact]
+        public async Task Returns_no_body_for_failed_HEAD_request()
+        {
+            // Arrange
+            const string route = "/meetings/99999999";
+
+            // Act
+            (HttpResponseMessage httpResponse, string responseDocument) = await _testContext.ExecuteHeadAsync<string>(route);
+
+            // Assert
+            httpResponse.Should().HaveStatusCode(HttpStatusCode.NotFound);
+
+            responseDocument.Should().BeEmpty();
+        }
+
         [Fact]
         public async Task Can_get_primary_resources_with_include()
         {

test/TestBuildingBlocks/IntegrationTest.cs

@@ -14,6 +14,12 @@ public abstract class IntegrationTest
     {
         private static readonly IntegrationTestConfiguration IntegrationTestConfiguration = new IntegrationTestConfiguration();
 
+        public async Task<(HttpResponseMessage httpResponse, TResponseDocument responseDocument)> ExecuteHeadAsync<TResponseDocument>(string requestUrl,
+            Action<HttpRequestHeaders> setRequestHeaders = null)
+        {
+            return await ExecuteRequestAsync<TResponseDocument>(HttpMethod.Head, requestUrl, null, null, setRequestHeaders);
+        }
+
         public async Task<(HttpResponseMessage httpResponse, TResponseDocument responseDocument)> ExecuteGetAsync<TResponseDocument>(string requestUrl,
             Action<HttpRequestHeaders> setRequestHeaders = null)
         {

test/UnitTests/Middleware/JsonApiRequestTests.cs

@@ -18,6 +18,12 @@ namespace UnitTests.Middleware
     public sealed class JsonApiRequestTests
     {
         [Theory]
+        [InlineData("HEAD", "/articles", true, EndpointKind.Primary, true)]
+        [InlineData("HEAD", "/articles/1", false, EndpointKind.Primary, true)]
+        [InlineData("HEAD", "/articles/1/author", false, EndpointKind.Secondary, true)]
+        [InlineData("HEAD", "/articles/1/tags", true, EndpointKind.Secondary, true)]
+        [InlineData("HEAD", "/articles/1/relationships/author", false, EndpointKind.Relationship, true)]
+        [InlineData("HEAD", "/articles/1/relationships/tags", true, EndpointKind.Relationship, true)]
         [InlineData("GET", "/articles", true, EndpointKind.Primary, true)]
         [InlineData("GET", "/articles/1", false, EndpointKind.Primary, true)]
         [InlineData("GET", "/articles/1/author", false, EndpointKind.Secondary, true)]