Expose JsonSerializerSettings in ApiClient

Created by: davidyee

In this PR, I expose the JsonSerializerSettings in the ApiClient so that serialization customizations can be done. For example, in my specific use-case, I wanted to add additional Converters to change the way JSON was being deserialized back into the csharp classes.

Fixes #4241 (closed)

I reviewed the comments made on this related PR #4466 and incorporated the feedback into this PR.

@mandrean (2017/08) @frankyjuang (2019/09) @shibayan (2020/02)

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modules/openapi-generator/src/main/resources/csharp/ApiClient.mustache

@@ -30,7 +30,7 @@ namespace {{packageName}}.Client
     /// </summary>
     {{>visibility}} partial class ApiClient
     {
-        private JsonSerializerSettings serializerSettings = new JsonSerializerSettings
+        public JsonSerializerSettings serializerSettings = new JsonSerializerSettings
         {
             ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor
         };

modules/openapi-generator/src/main/resources/csharp-netcore/ApiClient.mustache

@@ -160,6 +160,23 @@ namespace {{packageName}}.Client
     {
         private readonly String _baseUrl;
 
+        /// <summary>
+        /// Specifies the settings on a <see cref="JsonSerializer" /> object. 
+        /// These settings can be adjusted to accomodate custom serialization rules.
+        /// </summary>
+        public JsonSerializerSettings SerializerSettings { get; set; } = new JsonSerializerSettings
+        {
+            // OpenAPI generated types generally hide default constructors.
+            ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor,
+            ContractResolver = new DefaultContractResolver
+            {
+                NamingStrategy = new CamelCaseNamingStrategy
+                {
+                    OverrideSpecifiedNames = false
+                }
+            }
+        };
+
         /// <summary>
         /// Allows for extending request processing for <see cref="ApiClient"/> generated code.
         /// </summary>
@@ -258,7 +275,7 @@ namespace {{packageName}}.Client
             RestRequest request = new RestRequest(Method(method))
             {
                 Resource = path,
-                JsonSerializer = new CustomJsonCodec(configuration)
+                JsonSerializer = new CustomJsonCodec(SerializerSettings, configuration)
             };
 
             if (options.PathParameters != null)
@@ -406,7 +423,7 @@ namespace {{packageName}}.Client
             }
             else
             {
-                var customDeserializer = new CustomJsonCodec(configuration);
+                var customDeserializer = new CustomJsonCodec(SerializerSettings, configuration);
                 client.AddHandler("application/json", () => customDeserializer);
                 client.AddHandler("text/json", () => customDeserializer);
                 client.AddHandler("text/x-json", () => customDeserializer);
@@ -435,7 +452,7 @@ namespace {{packageName}}.Client
             InterceptRequest(req);
 
             IRestResponse<T> response;
-            if (RetryConfiguration.RetryPolicy != null)	
+            if (RetryConfiguration.RetryPolicy != null)
             {
                 var policy = RetryConfiguration.RetryPolicy;
                 var policyResult = policy.ExecuteAndCapture(() => client.Execute(req));
@@ -513,7 +530,7 @@ namespace {{packageName}}.Client
             }
             else
             {
-                var customDeserializer = new CustomJsonCodec(configuration);
+                var customDeserializer = new CustomJsonCodec(SerializerSettings, configuration);
                 client.AddHandler("application/json", () => customDeserializer);
                 client.AddHandler("text/json", () => customDeserializer);
                 client.AddHandler("text/x-json", () => customDeserializer);

samples/client/petstore/csharp/OpenAPIClient/src/Org.OpenAPITools/Client/ApiClient.cs

@@ -29,7 +29,7 @@ namespace Org.OpenAPITools.Client
     /// </summary>
     public partial class ApiClient
     {
-        private JsonSerializerSettings serializerSettings = new JsonSerializerSettings
+        public JsonSerializerSettings serializerSettings = new JsonSerializerSettings
         {
             ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor
         };

samples/client/petstore/csharp/OpenAPIClientNetStandard/src/Org.OpenAPITools/Client/ApiClient.cs

@@ -29,7 +29,7 @@ namespace Org.OpenAPITools.Client
     /// </summary>
     public partial class ApiClient
     {
-        private JsonSerializerSettings serializerSettings = new JsonSerializerSettings
+        public JsonSerializerSettings serializerSettings = new JsonSerializerSettings
         {
             ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor
         };

samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Client/ApiClient.cs

@@ -164,6 +164,23 @@ namespace Org.OpenAPITools.Client
     {
         private readonly String _baseUrl;
 
+        /// <summary>
+        /// Specifies the settings on a <see cref="JsonSerializer" /> object. 
+        /// These settings can be adjusted to accomodate custom serialization rules.
+        /// </summary>
+        public JsonSerializerSettings SerializerSettings { get; set; } = new JsonSerializerSettings
+        {
+            // OpenAPI generated types generally hide default constructors.
+            ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor,
+            ContractResolver = new DefaultContractResolver
+            {
+                NamingStrategy = new CamelCaseNamingStrategy
+                {
+                    OverrideSpecifiedNames = false
+                }
+            }
+        };
+
         /// <summary>
         /// Allows for extending request processing for <see cref="ApiClient"/> generated code.
         /// </summary>
@@ -262,7 +279,7 @@ namespace Org.OpenAPITools.Client
             RestRequest request = new RestRequest(Method(method))
             {
                 Resource = path,
-                JsonSerializer = new CustomJsonCodec(configuration)
+                JsonSerializer = new CustomJsonCodec(SerializerSettings, configuration)
             };
 
             if (options.PathParameters != null)
@@ -410,7 +427,7 @@ namespace Org.OpenAPITools.Client
             }
             else
             {
-                var customDeserializer = new CustomJsonCodec(configuration);
+                var customDeserializer = new CustomJsonCodec(SerializerSettings, configuration);
                 client.AddHandler("application/json", () => customDeserializer);
                 client.AddHandler("text/json", () => customDeserializer);
                 client.AddHandler("text/x-json", () => customDeserializer);
@@ -439,7 +456,7 @@ namespace Org.OpenAPITools.Client
             InterceptRequest(req);
 
             IRestResponse<T> response;
-            if (RetryConfiguration.RetryPolicy != null)	
+            if (RetryConfiguration.RetryPolicy != null)
             {
                 var policy = RetryConfiguration.RetryPolicy;
                 var policyResult = policy.ExecuteAndCapture(() => client.Execute(req));
@@ -516,7 +533,7 @@ namespace Org.OpenAPITools.Client
             }
             else
             {
-                var customDeserializer = new CustomJsonCodec(configuration);
+                var customDeserializer = new CustomJsonCodec(SerializerSettings, configuration);
                 client.AddHandler("application/json", () => customDeserializer);
                 client.AddHandler("text/json", () => customDeserializer);
                 client.AddHandler("text/x-json", () => customDeserializer);