feat: set up basiscs for ID fetching

src/JsonApiDotNetCore/Middleware/CurrentRequestMiddleware.cs

@@ -1,11 +1,13 @@
 using System;
+using System.ComponentModel;
 using System.Linq;
 using System.Threading.Tasks;
 using JsonApiDotNetCore.Configuration;
 using JsonApiDotNetCore.Internal;
 using JsonApiDotNetCore.Internal.Contracts;
 using JsonApiDotNetCore.Managers.Contracts;
 using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Routing;
 using Microsoft.Extensions.Primitives;
 
@@ -21,6 +23,7 @@ public class CurrentRequestMiddleware
         private ICurrentRequest _currentRequest;
         private IResourceGraph _resourceGraph;
         private IJsonApiOptions _options;
+        private RouteValueDictionary _routeValues;
         private IControllerResourceMapping _controllerResourceMapping;
 
         public CurrentRequestMiddleware(RequestDelegate next)
@@ -39,12 +42,15 @@ public async Task Invoke(HttpContext httpContext,
             _controllerResourceMapping = controllerResourceMapping;
             _resourceGraph = resourceGraph;
             _options = options;
+            _routeValues = httpContext.GetRouteData().Values;
             var requestResource = GetCurrentEntity();
             if (requestResource != null)
             {
-                _currentRequest.SetRequestResource(GetCurrentEntity());
+                _currentRequest.SetRequestResource(requestResource);
                 _currentRequest.IsRelationshipPath = PathIsRelationship();
-                _currentRequest.BasePath = GetBasePath(_currentRequest.GetRequestResource().ResourceName);
+                _currentRequest.BasePath = GetBasePath(requestResource.ResourceName);
+                _currentRequest.BaseId = GetBaseId();
+                _currentRequest.RelationshipId = GetRelationshipId();
             }
 
             if (IsValid())
@@ -53,50 +59,127 @@ public async Task Invoke(HttpContext httpContext,
             }
         }
 
-        private string GetBasePath(string entityName)
+        private string GetBaseId()
         {
-            var r = _httpContext.Request;
-            if (_options.RelativeLinks)
+            var resource = _currentRequest.GetRequestResource();
+            var individualComponents = SplitCurrentPath();
+            if (individualComponents.Length < 2)
             {
-                return GetNamespaceFromPath(r.Path, entityName);
+                return null;
             }
-            return $"{r.Scheme}://{r.Host}{GetNamespaceFromPath(r.Path, entityName)}";
+            var indexOfResource = individualComponents.ToList().FindIndex(c => c == resource.ResourceName);
+            var baseId = individualComponents.ElementAtOrDefault(indexOfResource + 1);
+            if (baseId == null)
+            {
+                return null;
+            }
+            CheckIdType(baseId, resource.IdentityType);
+            return baseId;
         }
+        private string GetRelationshipId()
+        {
+            var resource = _currentRequest.GetRequestResource();
+            if (!_currentRequest.IsRelationshipPath)
+            {
+                return null;
+            }
+            var components = SplitCurrentPath();
+            var toReturn = components.ElementAtOrDefault(4);
 
-        internal static string GetNamespaceFromPath(string path, string entityName)
+            if (toReturn == null)
+            {
+                return null;
+            }
+            var relType = _currentRequest.RequestRelationship.RightType;
+            var relResource = _resourceGraph.GetResourceContext(relType);
+            var relIdentityType = relResource.IdentityType;
+            CheckIdType(toReturn, relIdentityType);
+            return toReturn;
+        }
+        private string[] SplitCurrentPath()
         {
-            var entityNameSpan = entityName.AsSpan();
-            var pathSpan = path.AsSpan();
-            const char delimiter = '/';
-            for (var i = 0; i < pathSpan.Length; i++)
+            var path = _httpContext.Request.Path.Value;
+            var ns = $"/{GetNameSpace()}";
+            var nonNameSpaced = path.Replace(ns, "");
+            nonNameSpaced = nonNameSpaced.Trim('/');
+            var individualComponents = nonNameSpaced.Split('/');
+            return individualComponents;
+        }
+
+
+        private void CheckIdType(string value, Type idType)
+        {
+            try
             {
-                if (pathSpan[i].Equals(delimiter))
+                var converter = TypeDescriptor.GetConverter(idType);
+                if (converter != null)
                 {
-                    var nextPosition = i + 1;
-                    if (pathSpan.Length > i + entityNameSpan.Length)
+                    if (!converter.IsValid(value))
                     {
-                        var possiblePathSegment = pathSpan.Slice(nextPosition, entityNameSpan.Length);
-                        if (entityNameSpan.SequenceEqual(possiblePathSegment))
+                        throw new JsonApiException(500, $"We could not convert the id '{value}'");
+                    }
+                    else
+                    {
+                        if (idType == typeof(int))
                         {
-                            // check to see if it's the last position in the string
-                            //   or if the next character is a /
-                            var lastCharacterPosition = nextPosition + entityNameSpan.Length;
-
-                            if (lastCharacterPosition == pathSpan.Length || pathSpan.Length >= lastCharacterPosition + 2 && pathSpan[lastCharacterPosition].Equals(delimiter))
+                            if ((int)converter.ConvertFromString(value) < 0)
                             {
-                                return pathSpan.Slice(0, i).ToString();
+                                throw new JsonApiException(500, "The base ID is an integer, and it is negative.");
                             }
                         }
                     }
                 }
             }
+            catch (NotSupportedException)
+            {
+
+            }
 
-            return string.Empty;
+        }
+
+        private string GetBasePath(string resourceName = null)
+        {
+            var r = _httpContext.Request;
+            if (_options.RelativeLinks)
+            {
+                return GetNameSpace(resourceName);
+            }
+            var ns = GetNameSpace(resourceName);
+            var customRoute = GetCustomRoute(r.Path.Value, resourceName);
+            var toReturn = $"{r.Scheme}://{r.Host}/{ns}";
+            if(customRoute != null)
+            {
+                toReturn += $"/{customRoute}";
+            }
+            return toReturn;
+        }
+
+        private object GetCustomRoute(string path, string resourceName)
+        {
+            var ns = GetNameSpace();
+            var trimmedComponents = path.Trim('/').Split('/').ToList();
+            var resourceNameIndex = trimmedComponents.FindIndex(c => c == resourceName);
+            var newComponents = trimmedComponents.Take(resourceNameIndex ).ToArray();
+            var customRoute = string.Join('/', newComponents);
+            if(customRoute == ns)
+            {
+                return null;
+            }
+            else
+            {
+                return customRoute;
+            }
+        }
+
+        private string GetNameSpace(string resourceName = null)
+        {
+
+            return _options.Namespace;
         }
 
         protected bool PathIsRelationship()
         {
-            var actionName = (string)_httpContext.GetRouteData().Values["action"];
+            var actionName = (string)_routeValues["action"];
             return actionName.ToLower().Contains("relationships");
         }
 
@@ -124,7 +207,9 @@ private bool IsValidAcceptHeader(HttpContext context)
             foreach (var acceptHeader in acceptHeaders)
             {
                 if (ContainsMediaTypeParameters(acceptHeader) == false)
+                {
                     continue;
+                }
 
                 FlushResponse(context, 406);
                 return false;
@@ -165,16 +250,21 @@ private void FlushResponse(HttpContext context, int statusCode)
         /// <returns></returns>
         private ResourceContext GetCurrentEntity()
         {
-            var controllerName = (string)_httpContext.GetRouteValue("controller");
+            var controllerName = (string)_routeValues["controller"];
             if (controllerName == null)
+            {
                 return null;
+            }
             var resourceType = _controllerResourceMapping.GetAssociatedResource(controllerName);
             var requestResource = _resourceGraph.GetResourceContext(resourceType);
             if (requestResource == null)
+            {
                 return requestResource;
-            var rd = _httpContext.GetRouteData().Values;
-            if (rd.TryGetValue("relationshipName", out object relationshipName))
+            }
+            if (_routeValues.TryGetValue("relationshipName", out object relationshipName))
+            {
                 _currentRequest.RequestRelationship = requestResource.Relationships.Single(r => r.PublicRelationshipName == (string)relationshipName);
+            }
             return requestResource;
         }
     }

src/JsonApiDotNetCore/RequestServices/Contracts/ICurrentRequest.cs

@@ -29,6 +29,8 @@ public interface ICurrentRequest
         /// is the relationship attribute associated with the targeted relationship
         /// </summary>
         RelationshipAttribute RequestRelationship { get; set; }
+        string BaseId { get; set; }
+        string RelationshipId { get; set; }
 
         /// <summary>
         /// Sets the current context entity for this entire request

src/JsonApiDotNetCore/RequestServices/CurrentRequest.cs

@@ -10,6 +10,8 @@ class CurrentRequest : ICurrentRequest
         public string BasePath { get; set; }
         public bool IsRelationshipPath { get; set; }
         public RelationshipAttribute RequestRelationship { get; set; }
+        public string BaseId { get; set; }
+        public string RelationshipId { get; set; }
 
         /// <summary>
         /// The main resource of the request.

test/JsonApiDotNetCoreExampleTests/Acceptance/Extensibility/CustomControllerTests.cs

@@ -128,7 +128,7 @@ public async Task CustomRouteControllers_Creates_Proper_Relationship_Links()
             var deserializedBody = JsonConvert.DeserializeObject<JObject>(body);
 
             var result = deserializedBody["data"]["relationships"]["owner"]["links"]["related"].ToString();
-            Assert.EndsWith($"{route}/owner", deserializedBody["data"]["relationships"]["owner"]["links"]["related"].ToString());
+            Assert.EndsWith($"{route}/owner", result);
         }
     }
 }