[chsarp-netcore]handle the exception to get correct error message.

Created by: Ghufz

Handled the exception for the response object which contains oneOf and anyOf relationship. For any type of error message received from target server it shows

"Exception has been thrown from target of an invocation." 

After Fix it throws following message which is as per the type of error received from target server.

1. Like for Auth related Error :

The JSON string `{"code":"AuthenticationFailure","message":"Cannot perform the operation. Invalid API key. Verify the API keyID, account and retry the operation.","messageId":"iam_api_key_is_invalid","messageParams":{},"}
` cannot be deserialized into any schema defined.

2. Target server not available

Error calling GetNtpPolicyList: No such host is known. (xyz.xyz12.com:443)

3. Invalid query :

The JSON string `{"code":"InvalidRequest","message":"The input query 'groupby(Health)' is invalid. The $apply query option must include both 'groupby' and 'aggregate' statements.","messageId":"odata_apply_query_must_include_groupby_and_aggregate_options","messageParams":{"1":"groupby(Health)"}}` cannot be deserialized into any schema defined.

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  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh

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

@@ -495,7 +495,14 @@ namespace {{packageName}}.Client
             // if the response type is oneOf/anyOf, call FromJSON to deserialize the data
             if (typeof({{{packageName}}}.{{modelPackage}}.AbstractOpenAPISchema).IsAssignableFrom(typeof(T)))
             {
-                response.Data = (T) typeof(T).GetMethod("FromJson").Invoke(null, new object[] { response.Content });
+                try
+                {
+                    response.Data = (T) typeof(T).GetMethod("FromJson").Invoke(null, new object[] { response.Content });
+                }
+                catch (Exception ex)
+                {
+                    throw ex.InnerException != null ? ex.InnerException : ex;
+                }
             }
             else if (typeof(T).Name == "Stream") // for binary response
             {

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

@@ -107,17 +107,25 @@
             {{#useOneOfDiscriminatorLookup}}
             {{#discriminator}}
 
-            string discriminatorValue = JObject.Parse(jsonString)["{{{propertyBaseName}}}"].ToString();
-            switch (discriminatorValue)
+            try
+            {
+                var discriminatorObj = JObject.Parse(jsonString)["{{{propertyBaseName}}}"];
+                string discriminatorValue =  discriminatorObj == null ?string.Empty :discriminatorObj.ToString();
+                switch (discriminatorValue)
+                {
+                    {{#mappedModels}}
+                    case "{{{mappingName}}}":
+                        new{{classname}} = new {{classname}}(JsonConvert.DeserializeObject<{{{modelName}}}>(jsonString, {{classname}}.AdditionalPropertiesSerializerSettings));
+                        return new{{classname}};
+                    {{/mappedModels}}
+                    default:
+                        System.Diagnostics.Debug.WriteLine(string.Format("Failed to lookup discriminator value `{0}` for {{classname}}. Possible values:{{#mappedModels}} {{{mappingName}}}{{/mappedModels}}", discriminatorValue));
+                        break;
+                }
+            }
+            catch (Exception ex)
             {
-                {{#mappedModels}}
-                case "{{{mappingName}}}":
-                    new{{classname}} = new {{classname}}(JsonConvert.DeserializeObject<{{{modelName}}}>(jsonString, {{classname}}.AdditionalPropertiesSerializerSettings));
-                    return new{{classname}};
-                {{/mappedModels}}
-                default:
-                    System.Diagnostics.Debug.WriteLine(string.Format("Failed to lookup discriminator value `{0}` for {{classname}}. Possible values:{{#mappedModels}} {{{mappingName}}}{{/mappedModels}}", discriminatorValue));
-                    break;
+                System.Diagnostics.Debug.WriteLine(string.Format("Failed to parse the json data : `{0}` {1}", jsonString, ex.ToString()));
             }
 
             {{/discriminator}}

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

@@ -494,7 +494,14 @@ namespace Org.OpenAPITools.Client
             // if the response type is oneOf/anyOf, call FromJSON to deserialize the data
             if (typeof(Org.OpenAPITools.Model.AbstractOpenAPISchema).IsAssignableFrom(typeof(T)))
             {
-                response.Data = (T) typeof(T).GetMethod("FromJson").Invoke(null, new object[] { response.Content });
+                try
+                {
+                    response.Data = (T) typeof(T).GetMethod("FromJson").Invoke(null, new object[] { response.Content });
+                }
+                catch (Exception ex)
+                {
+                    throw ex.InnerException != null ? ex.InnerException : ex;
+                }
             }
             else if (typeof(T).Name == "Stream") // for binary response
             {

samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/Mammal.cs

@@ -170,21 +170,29 @@ namespace Org.OpenAPITools.Model
                 return newMammal;
             }
 
-            string discriminatorValue = JObject.Parse(jsonString)["className"].ToString();
-            switch (discriminatorValue)
+            try
             {
-                case "Pig":
-                    newMammal = new Mammal(JsonConvert.DeserializeObject<Pig>(jsonString, Mammal.AdditionalPropertiesSerializerSettings));
-                    return newMammal;
-                case "whale":
-                    newMammal = new Mammal(JsonConvert.DeserializeObject<Whale>(jsonString, Mammal.AdditionalPropertiesSerializerSettings));
-                    return newMammal;
-                case "zebra":
-                    newMammal = new Mammal(JsonConvert.DeserializeObject<Zebra>(jsonString, Mammal.AdditionalPropertiesSerializerSettings));
-                    return newMammal;
-                default:
-                    System.Diagnostics.Debug.WriteLine(string.Format("Failed to lookup discriminator value `{0}` for Mammal. Possible values: Pig whale zebra", discriminatorValue));
-                    break;
+                var discriminatorObj = JObject.Parse(jsonString)["className"];
+                string discriminatorValue =  discriminatorObj == null ?string.Empty :discriminatorObj.ToString();
+                switch (discriminatorValue)
+                {
+                    case "Pig":
+                        newMammal = new Mammal(JsonConvert.DeserializeObject<Pig>(jsonString, Mammal.AdditionalPropertiesSerializerSettings));
+                        return newMammal;
+                    case "whale":
+                        newMammal = new Mammal(JsonConvert.DeserializeObject<Whale>(jsonString, Mammal.AdditionalPropertiesSerializerSettings));
+                        return newMammal;
+                    case "zebra":
+                        newMammal = new Mammal(JsonConvert.DeserializeObject<Zebra>(jsonString, Mammal.AdditionalPropertiesSerializerSettings));
+                        return newMammal;
+                    default:
+                        System.Diagnostics.Debug.WriteLine(string.Format("Failed to lookup discriminator value `{0}` for Mammal. Possible values: Pig whale zebra", discriminatorValue));
+                        break;
+                }
+            }
+            catch (Exception ex)
+            {
+                System.Diagnostics.Debug.WriteLine(string.Format("Failed to parse the json data : `{0}` {1}", jsonString, ex.ToString()));
             }
 
             int match = 0;

samples/client/petstore/csharp-netcore/OpenAPIClient/src/Org.OpenAPITools/Model/NullableShape.cs

@@ -153,18 +153,26 @@ namespace Org.OpenAPITools.Model
                 return newNullableShape;
             }
 
-            string discriminatorValue = JObject.Parse(jsonString)["shapeType"].ToString();
-            switch (discriminatorValue)
+            try
             {
-                case "Quadrilateral":
-                    newNullableShape = new NullableShape(JsonConvert.DeserializeObject<Quadrilateral>(jsonString, NullableShape.AdditionalPropertiesSerializerSettings));
-                    return newNullableShape;
-                case "Triangle":
-                    newNullableShape = new NullableShape(JsonConvert.DeserializeObject<Triangle>(jsonString, NullableShape.AdditionalPropertiesSerializerSettings));
-                    return newNullableShape;
-                default:
-                    System.Diagnostics.Debug.WriteLine(string.Format("Failed to lookup discriminator value `{0}` for NullableShape. Possible values: Quadrilateral Triangle", discriminatorValue));
-                    break;
+                var discriminatorObj = JObject.Parse(jsonString)["shapeType"];
+                string discriminatorValue =  discriminatorObj == null ?string.Empty :discriminatorObj.ToString();
+                switch (discriminatorValue)
+                {
+                    case "Quadrilateral":
+                        newNullableShape = new NullableShape(JsonConvert.DeserializeObject<Quadrilateral>(jsonString, NullableShape.AdditionalPropertiesSerializerSettings));
+                        return newNullableShape;
+                    case "Triangle":
+                        newNullableShape = new NullableShape(JsonConvert.DeserializeObject<Triangle>(jsonString, NullableShape.AdditionalPropertiesSerializerSettings));
+                        return newNullableShape;
+                    default:
+                        System.Diagnostics.Debug.WriteLine(string.Format("Failed to lookup discriminator value `{0}` for NullableShape. Possible values: Quadrilateral Triangle", discriminatorValue));
+                        break;
+                }
+            }
+            catch (Exception ex)
+            {
+                System.Diagnostics.Debug.WriteLine(string.Format("Failed to parse the json data : `{0}` {1}", jsonString, ex.ToString()));
             }
 
             int match = 0;