Fix issue 383 - Wrong sync API deserialization

* adjust models to match sync API response for deserialization

* add runtime type resolution support, adjust method descriptions

Kontent.Ai.Delivery.Abstractions/ContentItems/IContentItem.cs

@@ -8,5 +8,5 @@ public interface IContentItem
     /// <summary>
     /// Represents system attributes of a content item.
     /// </summary>
-    public IContentItemSystemAttributes System { get; set; }
+    public IContentItemSystemAttributes System { get; }
 }

Kontent.Ai.Delivery.Abstractions/Sync/IDeliverySyncInitResponse.cs

@@ -3,7 +3,7 @@
 namespace Kontent.Ai.Delivery.Abstractions;
 
 /// <summary>
-/// Represents a response from Kontent.ai Delivery API that contains a continuation token and .
+/// Represents a response from Kontent.ai Sync API. Response includes continuation token for subsequent synchronization calls. Sync initialization should always return an empty list.
 /// </summary>
 public interface IDeliverySyncInitResponse : IResponse
 {

Kontent.Ai.Delivery.Abstractions/Sync/IDeliverySyncResponse.cs

@@ -3,12 +3,12 @@
 namespace Kontent.Ai.Delivery.Abstractions;
 
 /// <summary>
-/// Represents a response from Kontent.ai Delivery API that contains a taxonomy group.
+/// Represents a response from Kontent.ai Sync API that contains recently updated items. Response includes continuation token for subsequent synchronization calls.
 /// </summary>
 public interface IDeliverySyncResponse : IResponse
 {
     /// <summary>
-    /// Gets list of delta update items.
+    /// Gets the list of items delta updates.
     /// </summary>
     IList<ISyncItem> SyncItems { get; }
 }

Kontent.Ai.Delivery.Abstractions/Sync/ISyncItem.cs

@@ -8,29 +8,14 @@ namespace Kontent.Ai.Delivery.Abstractions;
 public interface ISyncItem
 {
     /// <summary>
-    /// Gets the content item's codename.
+    /// Retrieves runtime strongly typed item if CustomTypeProvider is registered, otherwise null.
     /// </summary>
-    string Codename { get; }
-
-    /// <summary>
-    /// Gets the content item's internal ID.
-    /// </summary>
-    Guid Id { get; }
-
-    /// <summary>
-    /// Gets the content item's type codename.
-    /// </summary>
-    string Type { get; }
-
-    /// <summary>
-    /// Gets the codename of the language that the content is in.
-    /// </summary>
-    string Language { get; }
-
+    object StronglyTypedData { get; }
+
     /// <summary>
-    /// Gets the content item's collection codename. For projects without collections enabled, the value is default.
+    /// Retrieves content item information and element values.
     /// </summary>
-    string Collection { get; }
+    ISyncItemData Data { get; }
 
     /// <summary>
     /// Gets the information whether the content item was modified or deleted since the last synchronization.

Kontent.Ai.Delivery.Abstractions/Sync/ISyncItemData.cs

@@ -0,0 +1,14 @@
+using System.Collections.Generic;
+
+namespace Kontent.Ai.Delivery.Abstractions;
+
+/// <summary>
+/// Represents a delta update.
+/// </summary>
+public interface ISyncItemData : IContentItem
+{
+    /// <summary>
+    /// Retrieves key:value pairs representing content item elements.
+    /// </summary>
+    Dictionary<string, object> Elements { get; }
+}

Kontent.Ai.Delivery.Caching/DeliveryClientCache.cs

@@ -160,7 +160,7 @@ public async Task<IDeliveryLanguageListingResponse> GetLanguagesAsync(IEnumerabl
         /// <summary>
         /// Initializes synchronization of changes in content items based on the specified parameters. After the initialization, you'll get an X-Continuation token in the response.
         /// </summary>
-        /// <param name="parameters">A collection of query parameters, for example, for filtering.</param>
+        /// <param name="parameters">A collection of query parameters, for example to limit synchronization to only a subset of collections or content types.</param>
         /// <returns>The <see cref="IDeliverySyncInitResponse"/> instance that represents the sync init response that contains continuation token needed for further sync execution.</returns>
         public Task<IDeliverySyncInitResponse> PostSyncInitAsync(IEnumerable<IQueryParameter> parameters = null)
         {

Kontent.Ai.Delivery.Tests/DeliveryClientTests.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Net;
@@ -14,7 +13,6 @@
 using Kontent.Ai.Delivery.ContentItems;
 using Kontent.Ai.Delivery.ContentItems.RichText.Blocks;
 using Kontent.Ai.Delivery.SharedModels;
-using Kontent.Ai.Delivery.Sync;
 using Kontent.Ai.Delivery.Tests.Factories;
 using Kontent.Ai.Delivery.Tests.Models;
 using Kontent.Ai.Delivery.Tests.Models.ContentTypes;
@@ -1851,41 +1849,85 @@ public async Task SyncApi_PostSyncInitAsync_WithParameters_GetContinuationToken(
         }
 
         [Fact]
-        public async Task SyncApi_GetSyncAsync_GetSyncItems()
+        public async Task SyncApi_GetSyncAsync_GetSyncItems_WithTypeProvider_ReturnsStronglyTypedData()
         {
             var mockedResponse = await File.ReadAllTextAsync(Path.Combine(Environment.CurrentDirectory, $"Fixtures{Path.DirectorySeparatorChar}DeliveryClient{Path.DirectorySeparatorChar}sync.json"));
 
-            var expectedValue = JObject.Parse(mockedResponse).SelectToken("items").ToObject<IList<SyncItem>>();
-            
+            var expectedItems = JObject.Parse(mockedResponse).SelectToken("items").ToObject<List<JObject>>();
+
             _mockHttp
                 .When($"{_baseUrl}/sync")
                 .WithHeaders("X-Continuation", "token")
                 .Respond(new[] { new KeyValuePair<string, string>("X-Continuation", "token"), }, "application/json", mockedResponse);
 
-            var client = InitializeDeliveryClientWithCustomModelProvider(_mockHttp);
+            var client = InitializeDeliveryClientWithACustomTypeProvider(_mockHttp);
 
             var sync = await client.GetSyncAsync("token");
 
             Assert.NotNull(sync.ApiResponse.ContinuationToken);
 
             Assert.Equal(2, sync.SyncItems.Count);
 
-            Assert.Equal(expectedValue[0].Codename, sync.SyncItems[0].Codename);
-            Assert.Equal(expectedValue[0].Id, sync.SyncItems[0].Id);
-            Assert.Equal(expectedValue[0].Type, sync.SyncItems[0].Type);
-            Assert.Equal(expectedValue[0].Language, sync.SyncItems[0].Language);
-            Assert.Equal(expectedValue[0].Collection, sync.SyncItems[0].Collection);
-            Assert.Equal(expectedValue[0].ChangeType, sync.SyncItems[0].ChangeType);
-            Assert.Equal(expectedValue[0].Timestamp, sync.SyncItems[0].Timestamp);
-
-            Assert.Equal(expectedValue[1].Codename, sync.SyncItems[1].Codename);
-            Assert.Equal(expectedValue[1].Id, sync.SyncItems[1].Id);
-            Assert.Equal(expectedValue[1].Type, sync.SyncItems[1].Type);
-            Assert.Equal(expectedValue[1].Language, sync.SyncItems[1].Language);
-            Assert.Equal(expectedValue[1].Collection, sync.SyncItems[1].Collection);
-            Assert.Equal(expectedValue[1].ChangeType, sync.SyncItems[1].ChangeType);
-            Assert.Equal(expectedValue[1].Timestamp, sync.SyncItems[1].Timestamp);
+            for (int i = 0; i < expectedItems.Count; i++)
+            {
+                var article = sync.SyncItems[i].StronglyTypedData as Article;
+                var expectedItem = expectedItems[i];
+                var expectedElementValues = expectedItem["data"]["elements"];
+
+                AssertSystemPropertiesEquality(expectedItem["data"]["system"].ToObject<JObject>(), article.System);
+                Assert.NotNull(article);
+                Assert.Equal(expectedElementValues["title"]["value"].ToString(), article.Title);   
+                Assert.Equal(expectedItem["change_type"].ToString(), sync.SyncItems[i].ChangeType);
+                Assert.Equal(DateTime.Parse(expectedItem["timestamp"].ToString()), DateTime.Parse(sync.SyncItems[i].Timestamp.ToString()));
+            }
         }
+
+        [Fact]
+        public async Task SyncApi_GetSyncAsync_GetSyncItems_WithoutTypeProvider_ReturnsGenericData()
+        {
+            var mockedResponse = await File.ReadAllTextAsync(Path.Combine(Environment.CurrentDirectory, $"Fixtures{Path.DirectorySeparatorChar}DeliveryClient{Path.DirectorySeparatorChar}sync.json"));
+
+            var expectedItems = JObject.Parse(mockedResponse).SelectToken("items").ToObject<List<JObject>>();
+
+            _mockHttp
+                .When($"{_baseUrl}/sync")
+                .WithHeaders("X-Continuation", "token")
+                .Respond(new[] { new KeyValuePair<string, string>("X-Continuation", "token"), }, "application/json", mockedResponse);
+
+            var client = InitializeDeliveryClientWithCustomModelProvider(_mockHttp, new PropertyMapper(), new TypeProvider());
+
+            var sync = await client.GetSyncAsync("token");
+
+            Assert.NotNull(sync.ApiResponse.ContinuationToken);
+
+            Assert.Equal(2, sync.SyncItems.Count);
+
+            for (int i = 0; i < expectedItems.Count; i++)
+            {
+                var syncItemData = sync.SyncItems[i].Data;
+                var expectedItem = expectedItems[i];
+                var expectedElementValues = expectedItem["data"]["elements"];
+
+                AssertSystemPropertiesEquality(expectedItem["data"]["system"].ToObject<JObject>(), sync.SyncItems[i].Data.System);
+                Assert.Null(sync.SyncItems[i].StronglyTypedData);
+                Assert.NotNull(syncItemData.Elements["title"]);
+                Assert.Equal(expectedElementValues["title"], syncItemData.Elements["title"]);
+                Assert.Equal(expectedItem["change_type"].ToString(), sync.SyncItems[i].ChangeType);
+                Assert.Equal(DateTime.Parse(expectedItem["timestamp"].ToString()), DateTime.Parse(sync.SyncItems[i].Timestamp.ToString()));
+            }
+        }
+
+        private void AssertSystemPropertiesEquality(JObject expectedSystemValues, IContentItemSystemAttributes system)
+        {
+                Assert.Equal(expectedSystemValues["codename"].ToString(), system.Codename.ToString());
+                Assert.Equal(expectedSystemValues["name"].ToString(), system.Name.ToString());
+                Assert.Equal(expectedSystemValues["id"].ToString(), system.Id.ToString());
+                Assert.Equal(expectedSystemValues["type"].ToString(), system.Type.ToString());
+                Assert.Equal(expectedSystemValues["language"].ToString(), system.Language.ToString());
+                Assert.Equal(expectedSystemValues["collection"].ToString(), system.Collection.ToString());
+                Assert.Equal(expectedSystemValues["workflow_step"].ToString(), system.WorkflowStep.ToString());
+        }
+
 
         private DeliveryClient InitializeDeliveryClientWithACustomTypeProvider(MockHttpMessageHandler handler)
         {

Kontent.Ai.Delivery.Tests/Fixtures/DeliveryClient/sync.json

@@ -1,22 +1,48 @@
 {
   "items": [
     {
-      "codename": "hello_world",
-      "id": "7adfb82a-1386-4228-bcc2-45073a0355f6",
-      "type": "article",
-      "language": "default",
-      "collection": "default",
+      "data": {
+        "system": {
+          "codename": "hello_world",
+          "name": "Hello world!",
+          "id": "7adfb82a-1386-4228-bcc2-45073a0355f6",
+          "type": "article",
+          "language": "default",
+          "collection": "default",
+          "workflow_step": "published"
+        },
+        "elements": {
+          "title": {
+            "type": "text",
+            "name": "Title",
+            "value": "Hello world!"
+          }
+        }
+      },
       "change_type": "changed",
       "timestamp": "2022-10-06T08:38:40.0088127Z"
     },
     {
-      "codename": "bye__world",
-      "id": "42a3cfbd-4967-43e7-987b-e1e69c483e26",
-      "type": "article",
-      "language": "default",
-      "collection": "default",
+      "data": {
+        "system": {
+          "codename": "bye_world",
+          "name": "Bye world!",
+          "id": "42a3cfbd-4967-43e7-987b-e1e69c483e26",
+          "type": "article",
+          "language": "default",
+          "collection": "default",
+          "workflow_step": "published"
+        },
+        "elements": {
+          "title": {
+            "type": "text",
+            "name": "Title",
+            "value": "Bye world!"
+          }
+        }
+      },
       "change_type": "deleted",
       "timestamp": "2022-10-06T08:38:47.3613558Z"
     }
   ]
-}
+}

Kontent.Ai.Delivery/DeliveryClient.cs

@@ -314,6 +314,11 @@ public async Task<IDeliveryLanguageListingResponse> GetLanguagesAsync(IEnumerabl
             return new DeliveryLanguageListingResponse(response, languages.ToList<ILanguage>(), pagination);
         }
 
+        /// <summary>
+        /// Initializes synchronization of changes in content items based on the specified parameters. After the initialization, you'll get an X-Continuation token in the response.
+        /// </summary>
+        /// <param name="parameters">A collection of query parameters, for example to limit synchronization to only a subset of collections or content types.</param>
+        /// <returns>The <see cref="IDeliverySyncInitResponse"/> instance that represents the sync init response that contains continuation token needed for further sync execution.</returns>
         public async Task<IDeliverySyncInitResponse> PostSyncInitAsync(IEnumerable<IQueryParameter> parameters = null)
         {
             var endpointUrl = UrlBuilder.GetSyncInitUrl(parameters);
@@ -326,9 +331,14 @@ public async Task<IDeliverySyncInitResponse> PostSyncInitAsync(IEnumerable<IQuer
 
             var content = await response.GetJsonContentAsync();
             var items = content["items"].ToObject<List<SyncItem>>(Serializer);
+
             return new DeliverySyncInitResponse(response, items.ToList<ISyncItem>());
         }
 
+        /// <summary>
+        /// Retrieve a list of delta updates to recently changed content items in the specified project. The types of items you get is determined by the X-Continuation token you use.
+        /// </summary>
+        /// <returns>The <see cref="IDeliverySyncResponse"/> instance that represents the sync response that contains collection of delta updates and continuation token needed for further sync execution.</returns>
         public async Task<IDeliverySyncResponse> GetSyncAsync(string continuationToken)
         {
             var endpointUrl = UrlBuilder.GetSyncUrl();
@@ -340,10 +350,20 @@ public async Task<IDeliverySyncResponse> GetSyncAsync(string continuationToken)
             }
 
             var content = await response.GetJsonContentAsync();
-            var items = content["items"].ToObject<List<SyncItem>>(Serializer);
-            return new DeliverySyncResponse(response, items.ToList<ISyncItem>());
+            var syncItems = content["items"].ToObject<List<SyncItem>>(Serializer);
+
+            var itemModels = await Task.WhenAll(syncItems.Select(async syncItem =>
+            {
+                // use TypeProvider from DI container to select a model
+                var mappedModel = await ModelProvider.GetContentItemModelAsync<object>(JToken.FromObject(syncItem.Data), new JObject());
+
+                return new SyncItem(mappedModel, syncItem.Data, syncItem.ChangeType, syncItem.Timestamp);
+            }));
+
+            return new DeliverySyncResponse(response, itemModels);
         }
 
+
         private async Task<ApiResponse> GetDeliveryResponseAsync(string endpointUrl, HttpMethod httpMethod, string continuationToken = null)
         {
             if (DeliveryOptions.CurrentValue.UsePreviewApi && DeliveryOptions.CurrentValue.UseSecureAccess)

Kontent.Ai.Delivery/Sync/DeliverySyncResponse.cs

@@ -22,7 +22,7 @@ internal DeliverySyncResponse(IApiResponse response, IList<ISyncItem> syncItems)
         SyncItems = syncItems;
     }
 
-    internal DeliverySyncResponse(IApiResponse response) 
+    internal DeliverySyncResponse(IApiResponse response)
         : base(response)
     {
     }

Kontent.Ai.Delivery/Sync/SyncItem.cs

@@ -5,27 +5,14 @@
 namespace Kontent.Ai.Delivery.Sync;
 
 /// <inheritdoc/>
-public class SyncItem : ISyncItem
+internal sealed class SyncItem : ISyncItem
 {
     /// <inheritdoc/>
-    [JsonProperty("codename")]
-    public string Codename { get; internal set; }
+    public object StronglyTypedData { get; internal set; }
 
     /// <inheritdoc/>
-    [JsonProperty("id")]
-    public Guid Id { get; internal set; }
-
-    /// <inheritdoc/>
-    [JsonProperty("type")]
-    public string Type { get; internal set; }
-
-    /// <inheritdoc/>
-    [JsonProperty("language")]
-    public string Language { get; internal set; }
-
-    /// <inheritdoc/>
-    [JsonProperty("collection")]
-    public string Collection { get; internal set; }
+    [JsonProperty("data")]
+    public ISyncItemData Data { get; internal set; }
 
     /// <inheritdoc/>
     [JsonProperty("change_type")]
@@ -36,10 +23,14 @@ public class SyncItem : ISyncItem
     public DateTime Timestamp { get; internal set; }
 
     /// <summary>
-    /// Constructor used for deserialization (e.g. for caching purposes), contains no logic.
+    /// Initializes a new instance of <see cref="SyncItem"/> class.
     /// </summary>
     [JsonConstructor]
-    public SyncItem()
+    public SyncItem(object stronglyTypedData, ISyncItemData data, string changeType, DateTime timestamp)
     {
+        StronglyTypedData = stronglyTypedData;
+        Data = data;
+        ChangeType = changeType;
+        Timestamp = timestamp;
     }
 }