adds support for type discriminator during deserialization

.gitignore

@@ -444,4 +444,6 @@ $RECYCLE.BIN/
 reports/
 
 ## Java preference files
-*.prefs
+*.prefs
+
+samples/

.vscode/settings.json

@@ -16,7 +16,10 @@
         "squareup"
     ],
     "cSpell.words": [
+        "deserialization",
+        "Kiota",
         "npmrc",
+        "openapi",
         "serializers"
     ],
     "java.configuration.updateBuildConfiguration": "automatic"

CHANGELOG.md

@@ -9,6 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Adds support for downcast of types during deserialization according to the discriminator information in the description (CSharp/Go/Java/TypeScript). [#646](https://github.com/microsoft/kiota/issues/646)
+- Adds support for generating interfaces for models in Go. [#646](https://github.com/microsoft/kiota/issues/646)
+- Adds support for generating functions (as opposed to methods or static methods) in the generator (used in TypeScript for discriminator factories). [#646](https://github.com/microsoft/kiota/issues/646)
 - Added support for global error handling in python abstractions #1289
 - Added a HTTPRequestAdapter for python Requests library #1251
 

abstractions/dotnet/src/IRequestAdapter.cs

@@ -29,20 +29,22 @@ public interface IRequestAdapter
         /// Executes the HTTP request specified by the given RequestInformation and returns the deserialized response model.
         /// </summary>
         /// <param name="requestInfo">The RequestInformation object to use for the HTTP request.</param>
+        /// <param name="factory">The factory of the response model to deserialize the response into.</param>
         /// <param name="responseHandler">The response handler to use for the HTTP request instead of the default handler.</param>
         /// <param name="errorMapping">The error factories mapping to use in case of a failed request.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> to use for cancelling the requests.</param>
         /// <returns>The deserialized response model.</returns>
-        Task<ModelType> SendAsync<ModelType>(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, Func<IParsable>> errorMapping = default, CancellationToken cancellationToken = default) where ModelType : IParsable;
+        Task<ModelType> SendAsync<ModelType>(RequestInformation requestInfo, ParsableFactory<ModelType> factory, IResponseHandler responseHandler = default, Dictionary<string, ParsableFactory<IParsable>> errorMapping = default, CancellationToken cancellationToken = default) where ModelType : IParsable;
         /// <summary>
         /// Executes the HTTP request specified by the given RequestInformation and returns the deserialized response model collection.
         /// </summary>
         /// <param name="requestInfo">The RequestInformation object to use for the HTTP request.</param>
+        /// <param name="factory">The factory of the response model to deserialize the response into.</param>
         /// <param name="responseHandler">The response handler to use for the HTTP request instead of the default handler.</param>
         /// <param name="errorMapping">The error factories mapping to use in case of a failed request.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> to use for cancelling the requests.</param>
         /// <returns>The deserialized response model collection.</returns>
-        Task<IEnumerable<ModelType>> SendCollectionAsync<ModelType>(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, Func<IParsable>> errorMapping = default, CancellationToken cancellationToken = default) where ModelType : IParsable;
+        Task<IEnumerable<ModelType>> SendCollectionAsync<ModelType>(RequestInformation requestInfo, ParsableFactory<ModelType> factory, IResponseHandler responseHandler = default, Dictionary<string, ParsableFactory<IParsable>> errorMapping = default, CancellationToken cancellationToken = default) where ModelType : IParsable;
         /// <summary>
         /// Executes the HTTP request specified by the given RequestInformation and returns the deserialized primitive response model.
         /// </summary>
@@ -51,7 +53,7 @@ public interface IRequestAdapter
         /// <param name="errorMapping">The error factories mapping to use in case of a failed request.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> to use for cancelling the requests.</param>
         /// <returns>The deserialized primitive response model.</returns>
-        Task<ModelType> SendPrimitiveAsync<ModelType>(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, Func<IParsable>> errorMapping = default, CancellationToken cancellationToken = default);
+        Task<ModelType> SendPrimitiveAsync<ModelType>(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, ParsableFactory<IParsable>> errorMapping = default, CancellationToken cancellationToken = default);
         /// <summary>
         /// Executes the HTTP request specified by the given RequestInformation and returns the deserialized primitive response model collection.
         /// </summary>
@@ -60,7 +62,7 @@ public interface IRequestAdapter
         /// <param name="errorMapping">The error factories mapping to use in case of a failed request.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> to use for cancelling the requests.</param>
         /// <returns>The deserialized primitive response model collection.</returns>
-        Task<IEnumerable<ModelType>> SendPrimitiveCollectionAsync<ModelType>(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, Func<IParsable>> errorMapping = default, CancellationToken cancellationToken = default);
+        Task<IEnumerable<ModelType>> SendPrimitiveCollectionAsync<ModelType>(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, ParsableFactory<IParsable>> errorMapping = default, CancellationToken cancellationToken = default);
         /// <summary>
         /// Executes the HTTP request specified by the given RequestInformation with no return content.
         /// </summary>
@@ -69,7 +71,7 @@ public interface IRequestAdapter
         /// <param name="errorMapping">The error factories mapping to use in case of a failed request.</param>
         /// <param name="cancellationToken">The <see cref="CancellationToken"/> to use for cancelling the requests.</param>
         /// <returns>A Task to await completion.</returns>
-        Task SendNoContentAsync(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, Func<IParsable>> errorMapping = default, CancellationToken cancellationToken = default);
+        Task SendNoContentAsync(RequestInformation requestInfo, IResponseHandler responseHandler = default, Dictionary<string, ParsableFactory<IParsable>> errorMapping = default, CancellationToken cancellationToken = default);
         /// <summary>
         /// The base url for every request.
         /// </summary>

abstractions/dotnet/src/IResponseHandler.cs

@@ -22,6 +22,6 @@ public interface IResponseHandler
         /// <typeparam name="NativeResponseType">The type of the native response object.</typeparam>
         /// <typeparam name="ModelType">The type of the response model object.</typeparam>
         /// <returns>A task that represents the asynchronous operation and contains the deserialized response.</returns>
-        Task<ModelType> HandleResponseAsync<NativeResponseType, ModelType>(NativeResponseType response, Dictionary<string, Func<IParsable>> errorMappings);
+        Task<ModelType> HandleResponseAsync<NativeResponseType, ModelType>(NativeResponseType response, Dictionary<string, ParsableFactory<IParsable>> errorMappings);
     }
 }

abstractions/dotnet/src/Microsoft.Kiota.Abstractions.csproj

@@ -6,7 +6,7 @@
     <LangVersion>latest</LangVersion>
     <PublishRepositoryUrl>true</PublishRepositoryUrl>
     <RepositoryUrl>https://github.com/microsoft/kiota</RepositoryUrl>
-    <Version>1.0.30</Version>
+    <Version>1.0.31</Version>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <!-- Enable this line once we go live to prevent breaking changes -->

abstractions/dotnet/src/NativeResponseHandler.cs

@@ -22,10 +22,10 @@ public class NativeResponseHandler : IResponseHandler
         /// <summary>
         /// The error mappings for the response to use when deserializing failed responses bodies. Where an error code like 401 applies specifically to that status code, a class code like 4XX applies to all status codes within the range if an the specific error code is not present.
         /// </summary>
-        public Dictionary<string, Func<IParsable>> ErrorMappings { get; set; }
+        public Dictionary<string, ParsableFactory<IParsable>> ErrorMappings { get; set; }
 
         /// <inheritdoc />
-        public Task<ModelType> HandleResponseAsync<NativeResponseType, ModelType>(NativeResponseType response, Dictionary<string, Func<IParsable>> errorMappings)
+        public Task<ModelType> HandleResponseAsync<NativeResponseType, ModelType>(NativeResponseType response, Dictionary<string, ParsableFactory<IParsable>> errorMappings)
         {
             Value = response;
             ErrorMappings = errorMappings;

abstractions/dotnet/src/serialization/IParseNode.cs

@@ -91,8 +91,9 @@ public interface IParseNode
         /// <summary>
         /// Gets the collection of model objects values of the node.
         /// </summary>
+        /// <param name="factory">The factory to use to create the model object.</param>
         /// <returns>The collection of model objects values.</returns>
-        IEnumerable<T> GetCollectionOfObjectValues<T>() where T : IParsable;
+        IEnumerable<T> GetCollectionOfObjectValues<T>(ParsableFactory<T> factory) where T : IParsable;
         /// <summary>
         /// Gets the enum value of the node.
         /// </summary>
@@ -101,14 +102,9 @@ public interface IParseNode
         /// <summary>
         /// Gets the model object value of the node.
         /// </summary>
+        /// <param name="factory">The factory to use to create the model object.</param>
         /// <returns>The model object value of the node.</returns>
-        T GetObjectValue<T>() where T : IParsable;
-        /// <summary>
-        /// Gets the resulting error from the node.
-        /// </summary>
-        /// <returns>The error object value of the node.</returns>
-        /// <param name="factory">The error factory.</param>
-        IParsable GetErrorValue(Func<IParsable> factory);
+        T GetObjectValue<T>(ParsableFactory<T> factory) where T : IParsable;
         /// <summary>
         /// Callback called before the node is deserialized.
         /// </summary>

abstractions/dotnet/src/serialization/ParsableFactory.cs

@@ -0,0 +1,15 @@
+// ------------------------------------------------------------------------------
+//  Copyright (c) Microsoft Corporation.  All Rights Reserved.  Licensed under the MIT License.  See License in the project root for license information.
+// ------------------------------------------------------------------------------
+
+using System;
+
+namespace Microsoft.Kiota.Abstractions.Serialization;
+
+/// <summary>
+/// Defines the factory for creating parsable objects.
+/// </summary>
+/// <param name="node">The <see cref="IParseNode">node</see> to parse use to get the discriminator value from the payload.</param>
+/// <returns>The <see cref="IParsable">parsable</see> object.</returns>
+/// <typeparam name="T">The type of the parsable object.</typeparam>
+public delegate T ParsableFactory<T>(IParseNode node) where T : IParsable;

abstractions/go/serialization/parsable.go

@@ -15,4 +15,4 @@ type Parsable interface {
 }
 
 // ParsableFactory is a factory for creating Parsable.
-type ParsableFactory func() Parsable
+type ParsableFactory func(parseNode ParseNode) (Parsable, error)

abstractions/go/serialization/parse_node.go

@@ -11,13 +11,13 @@ type ParseNode interface {
 	// GetChildNode returns a new parse node for the given identifier.
 	GetChildNode(index string) (ParseNode, error)
 	// GetCollectionOfObjectValues returns the collection of Parsable values from the node.
-	GetCollectionOfObjectValues(ctor func() Parsable) ([]Parsable, error)
+	GetCollectionOfObjectValues(ctor ParsableFactory) ([]Parsable, error)
 	// GetCollectionOfPrimitiveValues returns the collection of primitive values from the node.
 	GetCollectionOfPrimitiveValues(targetType string) ([]interface{}, error)
 	// GetCollectionOfEnumValues returns the collection of Enum values from the node.
 	GetCollectionOfEnumValues(parser func(string) (interface{}, error)) ([]interface{}, error)
 	// GetObjectValue returns the Parsable value from the node.
-	GetObjectValue(ctor func() Parsable) (Parsable, error)
+	GetObjectValue(ctor ParsableFactory) (Parsable, error)
 	// GetStringValue returns a String value from the nodes.
 	GetStringValue() (*string, error)
 	// GetBoolValue returns a Bool value from the nodes.

abstractions/java/lib/build.gradle

@@ -48,7 +48,7 @@ publishing {
     publications {
         gpr(MavenPublication) {
             artifactId 'kiota-abstractions'
-            version '1.0.26'
+            version '1.0.27'
             from(components.java)
         }
     }

abstractions/java/lib/src/main/java/com/microsoft/kiota/NativeResponseHandler.java

@@ -7,6 +7,7 @@
 import javax.annotation.Nullable;
 
 import com.microsoft.kiota.serialization.Parsable;
+import com.microsoft.kiota.serialization.ParsableFactory;
 
 /** Default response handler to access the native response object. */
 public class NativeResponseHandler implements ResponseHandler {
@@ -16,14 +17,14 @@ public class NativeResponseHandler implements ResponseHandler {
 
     /** The error mappings for the response to use when deserializing failed responses bodies. Where an error code like 401 applies specifically to that status code, a class code like 4XX applies to all status codes within the range if an the specific error code is not present. */
     @Nullable
-    public HashMap<String, Class<? extends Parsable>> errorMappings;
+    public HashMap<String, ParsableFactory<? extends Parsable>> errorMappings;
 
     /** {@inheritdoc} */
     @Nonnull
     @Override
     public <NativeResponseType, ModelType> CompletableFuture<ModelType> handleResponseAsync(
             NativeResponseType response,
-            HashMap<String, Class<? extends Parsable>> errorMappings) {
+            HashMap<String, ParsableFactory<? extends Parsable>> errorMappings) {
         this.value = response;
         this.errorMappings = errorMappings;
         return CompletableFuture.completedFuture(null);

abstractions/java/lib/src/main/java/com/microsoft/kiota/RequestAdapter.java

@@ -7,6 +7,7 @@
 import javax.annotation.Nullable;
 
 import com.microsoft.kiota.serialization.Parsable;
+import com.microsoft.kiota.serialization.ParsableFactory;
 import com.microsoft.kiota.serialization.SerializationWriterFactory;
 import com.microsoft.kiota.store.BackingStoreFactory;
 
@@ -26,23 +27,23 @@ public interface RequestAdapter {
     /**
      * Executes the HTTP request specified by the given RequestInformation and returns the deserialized response model.
      * @param requestInfo the request info to execute.
+     * @param factory the factory to create the parsable object from the type discriminator.
      * @param responseHandler The response handler to use for the HTTP request instead of the default handler.
-     * @param targetClass the class of the response model to deserialize the response into.
      * @param errorMappings the error factories mapping to use in case of a failed request.
      * @param <ModelType> the type of the response model to deserialize the response into.
      * @return a {@link CompletableFuture} with the deserialized response model.
      */
-    <ModelType extends Parsable> CompletableFuture<ModelType> sendAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final Class<ModelType> targetClass, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, Class<? extends Parsable>> errorMappings);
+    <ModelType extends Parsable> CompletableFuture<ModelType> sendAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final ParsableFactory<ModelType> factory, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, ParsableFactory<? extends Parsable>> errorMappings);
     /**
      * Executes the HTTP request specified by the given RequestInformation and returns the deserialized response model collection.
      * @param requestInfo the request info to execute.
+     * @param factory the factory to create the parsable object from the type discriminator.
      * @param responseHandler The response handler to use for the HTTP request instead of the default handler.
-     * @param targetClass the class of the response model to deserialize the response into.
      * @param errorMappings the error factories mapping to use in case of a failed request.
      * @param <ModelType> the type of the response model to deserialize the response into.
      * @return a {@link CompletableFuture} with the deserialized response model collection.
      */
-    <ModelType extends Parsable> CompletableFuture<Iterable<ModelType>> sendCollectionAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final Class<ModelType> targetClass, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, Class<? extends Parsable>> errorMappings);
+    <ModelType extends Parsable> CompletableFuture<Iterable<ModelType>> sendCollectionAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final ParsableFactory<ModelType> factory, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, ParsableFactory<? extends Parsable>> errorMappings);
     /**
      * Executes the HTTP request specified by the given RequestInformation and returns the deserialized primitive response model.
      * @param requestInfo the request info to execute.
@@ -52,7 +53,7 @@ public interface RequestAdapter {
      * @param <ModelType> the type of the response model to deserialize the response into.
      * @return a {@link CompletableFuture} with the deserialized primitive response model.
      */
-    <ModelType> CompletableFuture<ModelType> sendPrimitiveAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final Class<ModelType> targetClass, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, Class<? extends Parsable>> errorMappings);
+    <ModelType> CompletableFuture<ModelType> sendPrimitiveAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final Class<ModelType> targetClass, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, ParsableFactory<? extends Parsable>> errorMappings);
     /**
      * Executes the HTTP request specified by the given RequestInformation and returns the deserialized primitive collection response model.
      * @param requestInfo the request info to execute.
@@ -62,7 +63,7 @@ public interface RequestAdapter {
      * @param <ModelType> the type of the response model to deserialize the response into.
      * @return a {@link CompletableFuture} with the deserialized primitive collection response model.
      */
-    <ModelType> CompletableFuture<Iterable<ModelType>> sendPrimitiveCollectionAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final Class<ModelType> targetClass, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, Class<? extends Parsable>> errorMappings);
+    <ModelType> CompletableFuture<Iterable<ModelType>> sendPrimitiveCollectionAsync(@Nonnull final RequestInformation requestInfo, @Nonnull final Class<ModelType> targetClass, @Nullable final ResponseHandler responseHandler, @Nullable final HashMap<String, ParsableFactory<? extends Parsable>> errorMappings);
     /**
      * Sets The base url for every request.
      * @param baseUrl The base url for every request.