Removed more case-insensitive string comparisons. They are tricky, because they hide potential usages of property names instead of resource names, which only works with the default camel-case convention but breaks on kebab casing.

Author: Bart Koelman

src/JsonApiDotNetCore/Formatters/JsonApiInputFormatter.cs

@@ -15,7 +15,7 @@ public bool CanRead(InputFormatterContext context)
 
             var contentTypeString = context.HttpContext.Request.ContentType;
 
-            return contentTypeString == Constants.ContentType;
+            return contentTypeString == HeaderConstants.ContentType;
         }
 
         public async Task<InputFormatterResult> ReadAsync(InputFormatterContext context)

src/JsonApiDotNetCore/Formatters/JsonApiOutputFormatter.cs

@@ -15,7 +15,7 @@ public bool CanWriteResult(OutputFormatterCanWriteContext context)
 
             var contentTypeString = context.HttpContext.Request.ContentType;
 
-            return string.IsNullOrEmpty(contentTypeString) || contentTypeString == Constants.ContentType;
+            return string.IsNullOrEmpty(contentTypeString) || contentTypeString == HeaderConstants.ContentType;
         }
         public async Task WriteAsync(OutputFormatterWriteContext context)
         {

src/JsonApiDotNetCore/Formatters/JsonApiWriter.cs

@@ -50,7 +50,7 @@ public async Task WriteAsync(OutputFormatterWriteContext context)
             }
             else
             {
-                response.ContentType = Constants.ContentType;
+                response.ContentType = HeaderConstants.ContentType;
                 try
                 {
                     responseContent = SerializeResponse(context.Object, (HttpStatusCode)response.StatusCode);

src/JsonApiDotNetCore/Internal/Contracts/IResourceContextProvider.cs

@@ -16,7 +16,7 @@ public interface IResourceContextProvider
         /// <summary>
         /// Get the resource metadata by the DbSet property name
         /// </summary>
-        ResourceContext GetResourceContext(string exposedResourceName);
+        ResourceContext GetResourceContext(string resourceName);
 
         /// <summary>
         /// Get the resource metadata by the resource type

src/JsonApiDotNetCore/Internal/Constants.cs renamed to src/JsonApiDotNetCore/Internal/HeaderConstants.cs

@@ -1,6 +1,6 @@
 namespace JsonApiDotNetCore.Internal
 {
-    public static class Constants
+    public static class HeaderConstants
     {
         public const string AcceptHeader = "Accept";
         public const string ContentType = "application/vnd.api+json";

src/JsonApiDotNetCore/Internal/ResourceGraph.cs

@@ -15,20 +15,20 @@ public class ResourceGraph : IResourceGraph
         internal List<ValidationResult> ValidationResults { get; }
         private List<ResourceContext> Resources { get; }
 
-        public ResourceGraph(List<ResourceContext> entities, List<ValidationResult> validationResults = null)
+        public ResourceGraph(List<ResourceContext> resources, List<ValidationResult> validationResults = null)
         {
-            Resources = entities;
+            Resources = resources;
             ValidationResults = validationResults;
         }
 
         /// <inheritdoc />
         public ResourceContext[] GetResourceContexts() => Resources.ToArray();
         /// <inheritdoc />
-        public ResourceContext GetResourceContext(string entityName)
-            => Resources.SingleOrDefault(e => string.Equals(e.ResourceName, entityName, StringComparison.OrdinalIgnoreCase));
+        public ResourceContext GetResourceContext(string resourceName)
+            => Resources.SingleOrDefault(e => e.ResourceName == resourceName);
         /// <inheritdoc />
-        public ResourceContext GetResourceContext(Type entityType)
-            => Resources.SingleOrDefault(e => e.ResourceType == entityType);
+        public ResourceContext GetResourceContext(Type resourceType)
+            => Resources.SingleOrDefault(e => e.ResourceType == resourceType);
         /// <inheritdoc />
         public ResourceContext GetResourceContext<TResource>() where TResource : class, IIdentifiable
             => GetResourceContext(typeof(TResource));

src/JsonApiDotNetCore/Middleware/CurrentRequestMiddleware.cs

@@ -149,7 +149,7 @@ private static async Task<bool> IsValidContentTypeHeaderAsync(HttpContext contex
                 await FlushResponseAsync(context, new Error(HttpStatusCode.UnsupportedMediaType)
                 {
                     Title = "The specified Content-Type header value is not supported.",
-                    Detail = $"Please specify '{Constants.ContentType}' for the Content-Type header value."
+                    Detail = $"Please specify '{HeaderConstants.ContentType}' for the Content-Type header value."
                 });
 
                 return false;
@@ -159,7 +159,7 @@ private static async Task<bool> IsValidContentTypeHeaderAsync(HttpContext contex
 
         private static async Task<bool> IsValidAcceptHeaderAsync(HttpContext context)
         {
-            if (context.Request.Headers.TryGetValue(Constants.AcceptHeader, out StringValues acceptHeaders) == false)
+            if (context.Request.Headers.TryGetValue(HeaderConstants.AcceptHeader, out StringValues acceptHeaders) == false)
                 return true;
 
             foreach (var acceptHeader in acceptHeaders)
@@ -172,7 +172,7 @@ private static async Task<bool> IsValidAcceptHeaderAsync(HttpContext context)
                 await FlushResponseAsync(context, new Error(HttpStatusCode.NotAcceptable)
                 {
                     Title = "The specified Accept header value is not supported.",
-                    Detail = $"Please specify '{Constants.ContentType}' for the Accept header value."
+                    Detail = $"Please specify '{HeaderConstants.ContentType}' for the Accept header value."
                 });
                 return false;
             }
@@ -184,19 +184,19 @@ private static bool ContainsMediaTypeParameters(string mediaType)
             var incomingMediaTypeSpan = mediaType.AsSpan();
 
             // if the content type is not application/vnd.api+json then continue on
-            if (incomingMediaTypeSpan.Length < Constants.ContentType.Length)
+            if (incomingMediaTypeSpan.Length < HeaderConstants.ContentType.Length)
             {
                 return false;
             }
 
-            var incomingContentType = incomingMediaTypeSpan.Slice(0, Constants.ContentType.Length);
-            if (incomingContentType.SequenceEqual(Constants.ContentType.AsSpan()) == false)
+            var incomingContentType = incomingMediaTypeSpan.Slice(0, HeaderConstants.ContentType.Length);
+            if (incomingContentType.SequenceEqual(HeaderConstants.ContentType.AsSpan()) == false)
                 return false;
 
             // anything appended to "application/vnd.api+json;" will be considered a media type param
             return (
-                incomingMediaTypeSpan.Length >= Constants.ContentType.Length + 2
-                && incomingMediaTypeSpan[Constants.ContentType.Length] == ';'
+                incomingMediaTypeSpan.Length >= HeaderConstants.ContentType.Length + 2
+                && incomingMediaTypeSpan[HeaderConstants.ContentType.Length] == ';'
             );
         }
 

src/JsonApiDotNetCore/Middleware/DefaultTypeMatchFilter.cs

@@ -41,7 +41,7 @@ public void OnActionExecuting(ActionExecutingContext context)
 
         private bool IsJsonApiRequest(HttpRequest request)
         {
-            return (request.ContentType?.Equals(Constants.ContentType, StringComparison.OrdinalIgnoreCase) == true);
+            return request.ContentType == HeaderConstants.ContentType;
         }
 
         public void OnActionExecuted(ActionExecutedContext context) { /* noop */ }

src/JsonApiDotNetCore/Models/Annotation/HasManyThroughAttribute.cs

@@ -77,8 +77,8 @@ public HasManyThroughAttribute(string publicName, string internalThroughName, Li
         public override object GetValue(object entity)
         {
             var throughNavigationProperty = entity.GetType()
-                                        .GetProperties()
-                                        .SingleOrDefault(p => string.Equals(p.Name, InternalThroughName, StringComparison.OrdinalIgnoreCase));
+                .GetProperties()
+                .SingleOrDefault(p => p.Name == InternalThroughName);
 
             var throughEntities = throughNavigationProperty.GetValue(entity);
 

src/JsonApiDotNetCore/QueryParameterServices/Common/QueryParameterParser.cs

@@ -33,7 +33,7 @@ public virtual void Parse(DisableQueryAttribute disableQueryAttribute)
 
             foreach (var pair in _queryStringAccessor.Query)
             {
-                if (string.IsNullOrWhiteSpace(pair.Value))
+                if (string.IsNullOrEmpty(pair.Value))
                 {
                     throw new InvalidQueryStringParameterException(pair.Key, "Missing query string parameter value.",
                         $"Missing value for '{pair.Key}' query string parameter.");