I am using NSwag Studio to generate a C# client for an external Swagger API that I need to interact with. One of the properties on an API call that I am attempting to execute is a typed array.
From the specification.json:
"segmentValues": {
"description": "The table >",
"type": "array",
"items": {
"$ref": "#/definitions/DtoSegmentValue"
}
},
The generated code correctly recognizes this as a typed ICollection. From the Client.cs:
/// <summary>
/// The table &gt;
/// </summary>
[Newtonsoft.Json.JsonProperty("segmentValues", Required = Newtonsoft.Json.Required.Default, NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore)]
public System.Collections.Generic.ICollection<DtoSegmentValue> SegmentValues { get; set; }
However, in the generated code for this API call, NSwag attempts to convert this array to a <string,string> Dictionary and throws an Exception:
var json_ = Newtonsoft.Json.JsonConvert.SerializeObject(update, _settings.Value);
var dictionary_ = Newtonsoft.Json.JsonConvert.DeserializeObject<System.Collections.Generic.Dictionary<string, string>>(json_, _settings.Value); <-- this line throws the Exception
var content_ = new System.Net.Http.FormUrlEncodedContent(dictionary_);
The Exception:
Newtonsoft.Json.JsonReaderException: Unexpected character encountered while parsing value: [. Path 'segmentValues', line 1, position 18.
at Newtonsoft.Json.JsonTextReader.ReadStringValue(ReadType readType)
at Newtonsoft.Json.JsonTextReader.ReadAsString()
at Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, Boolean hasConverter)
The Exception clearly states that it is the array ( '[' ) that cannot be deserialized. But I cannot find any settings in NSwag studio that effect this line of generated code. So how do I reconfigure it to correctly handle an array in a body? I am assuming this is possible because it seems like very standard API behaviour to me.
The current configuration in the nswag.json file:
{
"runtime": "Net60",
"defaultVariables": null,
"documentGenerator": {
"fromDocument": {
"url": null,
"output": null,
"newLineBehavior": "Auto"
}
},
"codeGenerators": {
"openApiToCSharpClient": {
"clientBaseClass": null,
"configurationClass": null,
"generateClientClasses": true,
"generateClientInterfaces": true,
"clientBaseInterface": null,
"injectHttpClient": true,
"disposeHttpClient": true,
"protectedMethods": [],
"generateExceptionClasses": true,
"exceptionClass": "ApiException",
"wrapDtoExceptions": true,
"useHttpClientCreationMethod": false,
"httpClientType": "System.Net.Http.HttpClient",
"useHttpRequestMessageCreationMethod": false,
"useBaseUrl": true,
"generateBaseUrlProperty": true,
"generateSyncMethods": false,
"generatePrepareRequestAndProcessResponseAsAsyncMethods": false,
"exposeJsonSerializerSettings": false,
"clientClassAccessModifier": "public",
"typeAccessModifier": "public",
"generateContractsOutput": false,
"contractsNamespace": null,
"contractsOutputFilePath": null,
"parameterDateTimeFormat": "s",
"parameterDateFormat": "yyyy-MM-dd",
"generateUpdateJsonSerializerSettingsMethod": true,
"useRequestAndResponseSerializationSettings": false,
"serializeTypeInformation": false,
"queryNullValue": "",
"className": "ApiClient",
"operationGenerationMode": "SingleClientFromOperationId",
"additionalNamespaceUsages": [],
"additionalContractNamespaceUsages": [],
"generateOptionalParameters": false,
"generateJsonMethods": false,
"enforceFlagEnums": false,
"parameterArrayType": "System.Collections.Generic.IEnumerable",
"parameterDictionaryType": "System.Collections.Generic.IDictionary",
"responseArrayType": "System.Collections.Generic.ICollection",
"responseDictionaryType": "System.Collections.Generic.IDictionary",
"wrapResponses": true,
"wrapResponseMethods": [],
"generateResponseClasses": true,
"responseClass": "Response",
"namespace": "My.Api",
"requiredPropertiesMustBeDefined": false,
"dateType": "System.DateTimeOffset",
"jsonConverters": null,
"anyType": "object",
"dateTimeType": "System.DateTimeOffset",
"timeType": "System.TimeSpan",
"timeSpanType": "System.TimeSpan",
"arrayType": "System.Collections.Generic.ICollection",
"arrayInstanceType": "System.Collections.ObjectModel.Collection",
"dictionaryType": "System.Collections.Generic.IDictionary",
"dictionaryInstanceType": "System.Collections.Generic.Dictionary",
"arrayBaseType": "System.Collections.ObjectModel.Collection",
"dictionaryBaseType": "System.Collections.Generic.Dictionary",
"classStyle": "Poco",
"jsonLibrary": "NewtonsoftJson",
"generateDefaultValues": true,
"generateDataAnnotations": true,
"excludedTypeNames": [],
"excludedParameterNames": [],
"handleReferences": false,
"generateImmutableArrayProperties": false,
"generateImmutableDictionaryProperties": false,
"jsonSerializerSettingsTransformationMethod": null,
"inlineNamedArrays": false,
"inlineNamedDictionaries": false,
"inlineNamedTuples": true,
"inlineNamedAny": false,
"generateDtoTypes": true,
"generateOptionalPropertiesAsNullable": true,
"generateNullableReferenceTypes": false,
"templateDirectory": null,
"typeNameGeneratorType": null,
"propertyNameGeneratorType": null,
"enumNameGeneratorType": null,
"serviceHost": null,
"serviceSchemes": null,
"output": "Client.cs",
"newLineBehavior": "Auto"
}
}
}
I generated the C# client using NSwag studio and various different configurations in the client generation settings. But nothing effects the line of code that requires deserialization to a Dictionary<string, string>. Changing the data contract on the API that I am generating code for is not an option, since it is an external system that I have no influence over. It should also not be necessary since this seems like a standard implementation to me.
