I am trying to pass a JSON array to a WCF service. But it doesn't seem to work. I actually pulled an array [GetStudents] out the service and sent the exact same array back to the service [SaveStudents] and nothing (empty array) was received.
The JSON array is of the format:
[
{"Name":"John","Age":12},
{"Name":"Jane","Age":11},
{"Name":"Bill","Age":12}
]
And the contracts are of the following format:
//Contracts
[DataContract]
public class Student{
[DataMember]public string Name { get; set; }
[DataMember]public int Age{ get; set; }
}
[CollectionDataContract(Namespace = "")]
public class Students : List<Student>
{
[DataMember]public Endorsements() { }
[DataMember]public Endorsements(IEnumerable<Student> source) : base(source) { }
}
//Operations
public Students GetStudents()
{
var result = new Students();
result.Add(new Student(){Name="John",12});
result.Add(new Student(){Name="Jane",11});
result.Add(new Student(){Name="Bill",12});
return result;
}
//Operations
public void SaveStudents(Students list)
{
Console.WriteLine(list.Count); //It always returns zero
}
It there a particular way to send an array to a WCF REST service?
I had similar issue.
I was calling the service from a browser and the problem was Firefox dynamically changing the request content-type from 'application/json' to 'application-json;charset=utf-8'.
If you are calling the service from a browser, test it with non-firefox browser and if that was the case you need to remove the charset from the request content-type header
Related
I have an ASP.NET Web API 2 project to which I have added Swagger - Swashbuckle v5.6.0. Everything works fine. Swagger UI renders test endpoints for my API as expected.
I added a new Controller to my API. There is a GET action with a complex type parameter. For complex types, Web API tries to read the value from the message body. This is the default behaviour.
Here is my GET action:
[HttpGet]
[Route("search")]
[ResponseType(typeof(List<SearchModel>))]
public IHttpActionResult Search(SearchModel searchOptions)
{
//....
return Ok();
}
And her is my complex type:
public class SearchModel
{
public string FirstName { get; set; }
public string LastName { get; set; }
[DataType(DataType.EmailAddress)]
[EmailAddress]
public string Email { get; set; }
public string AddressLine1 { get; set; }
public string City { get; set; }
public string Telephone { get; set; }
public string MobilePhone { get; set; }
}
The problem:
But Swagger UI doesn't render body parameter field for my complex type in the GET action. For POST and PUT actions Swagger UI renders body parameter fields as expected but not for the complex type in my GET action.
As can be seen in the screenshot Swagger UI renders query parameters fields for attributes in my complex type instead of rendering a body parameter field for my type as it does in the case of POST and PUT.
My GET action is working fine when testing from Postman and filling the json in the body of the request. By setting breakpoint in the action inside Visual Studio I can see the values are bound to my object in the action parameter.
I have tried to decorate the parameter in my action with [FromBody] (which is the default for complex type) but same result.
Is this a bug in Swagger? Or am I missing something?
Sadly, you can't do what you want with Swagger. You can't send a request model in an HTTP GET method. You can however change the swagger UI to look like this:
but you won't be able to receive the model in your controller.
This is a known issue within the Swagger developers and it was discussed in 2016 and the final decision is that swagger won't support a request body in an HTTP GET method. Here is the link to the already closed issue.
You have three options here:
Leave the method as it is, and test it in Postman, but not in Swagger.
Follow the below steps to achieve the picture above, but please note, that it will only fix the UI part and you will always end up with null SearchModel in the controller when you press Try it out! in swagger.
Make it a [HttpPost method instead of [HttpGet].
How to make swagger UI display GET method with request body:
First, create one Attribute class:
public class ModelInBodyAttribute : Attribute
{
public ModelInBodyAttribute(string modelName, string description, bool isRequired)
{
this.ModelName = modelName;
this.Description = description;
this.IsRequired = IsRequired;
}
public string ModelName { get; set; }
public bool IsRequired { get; set; }
public string Description { get; set; }
}
Then you can decorate your method in the controller:
[ModelInBody(modelName: nameof(SearchModel), description: "My model description", isRequired: true)]
[HttpGet]
[Route("search")]
[ResponseType(typeof(List<SearchModel>))]
public IHttpActionResult Search(SearchModel searchOptions)
{
//....
return Ok(new List<SearchModel>());
}
After that create IOperationFilter class (ModelInBodyOperationFilter):
public class ModelInBodyOperationFilter : IOperationFilter
{
public void Apply(Operation operation, SchemaRegistry schemaRegistry, ApiDescription apiDescription)
{
var attribute = apiDescription.GetControllerAndActionAttributes<ModelInBodyAttribute>().FirstOrDefault();
if (attribute == null)
{
return;
}
operation.parameters.Clear();
operation.parameters.Add(new Parameter
{
name = attribute.ModelName,
description = attribute.Description,
#in = "body",
required = attribute.IsRequired,
schema = new Schema { #ref = $"#/definitions/{attribute.ModelName}" }
});
}
}
Lastly, don't forget to register the IOperationFilter in SwaggerConfig:
c.OperationFilter<ModelInBodyOperationFilter>();
When you send the request via swagger, you will notice that the Curl part is absolutely correct, but still, in your controller there is nothing.
There are endless discussions on whether you should have a PAYLOAD "Body content" in a GET request. As you mentioned it's supported by HTTP but you will find in the internet that many people suggest not to do it. I guess that swagger team also expect you not to use it.
I'm trying to send a PUT request with JSON data using the following client code:
const url = new URL(`${process.env.REACT_APP_API}/datas/edit/${id}`);
axios.put(url, data);
And on the server side, when I'm trying to look at in the HttpRequest.Form, the Controller throws InvalidOperationException exception . The message is Incorrect Content-Type: application/json;charset=UTF-8.
[HttpPut("edit/{id}")]
public void Edit([FromRoute] int id, [FromBody] Data data)
...
I also tried axios.put(url, JSON.stringify(data)); but server returns 415.
EDIT: I tried with Postman instead of my front-end:
public class A { public int /*or string*/ A1 { get; set; } }
[HttpPut("edit/{id}")]
public void EditQuestion([FromRoute] int id, [FromBody] A a) ...
IMPORTANT:
I shouldn't have looked at HttpRequest.Form because I'm sending JSON data and it should be parsed into my model.
I see the json response from postman returns a string, instead your "A" class has an int property for A1.
Try changing the class to:
public class A { public string A1 { get; set; } }
I get always null value from body why ?
I have no problem with using fiddler but postman is fail.
I have a web api like that:
[Route("api/account/GetToken/")]
[System.Web.Http.HttpPost]
public HttpResponseBody GetToken([FromBody] string value)
{
string result = value;
}
My postman data:
and header:
WebAPI is working as expected because you're telling it that you're sending this json object:
{ "username":"admin", "password":"admin" }
Then you're asking it to deserialize it as a string which is impossible since it's not a valid JSON string.
Solution 1:
If you want to receive the actual JSON as in the value of value will be:
value = "{ \"username\":\"admin\", \"password\":\"admin\" }"
then the string you need to set the body of the request in postman to is:
"{ \"username\":\"admin\", \"password\":\"admin\" }"
Solution 2 (I'm assuming this is what you want):
Create a C# object that matches the JSON so that WebAPI can deserialize it properly.
First create a class that matches your JSON:
public class Credentials
{
[JsonProperty("username")]
public string Username { get; set; }
[JsonProperty("password")]
public string Password { get; set; }
}
Then in your method use this:
[Route("api/account/GetToken/")]
[System.Web.Http.HttpPost]
public HttpResponseBody GetToken([FromBody] Credentials credentials)
{
string username = credentials.Username;
string password = credentials.Password;
}
You are posting an object and trying to bind it to a string.
Instead, create a type to represent that data:
public class Credentials
{
public string Username { get; set; }
public string Password { get; set; }
}
[Route("api/account/GetToken/")]
[System.Web.Http.HttpPost]
public HttpResponseBody GetToken([FromBody] Credentials value)
{
string result = value.Username;
}
Say you've got a model that looks like
public class UserModel
{
public string UserName { get; set; }
public DateTime? DateOfBirth { get; set; }
}
The DateOfBirth field isn't required, but could be specified. You have a Web API POST endpoint that looks like
[Route("")]
[AcceptVerbs("POST")]
public async Task<IHttpActionResult> Create(UserModel user)
{
}
And we've set the JSON serializer in start up like so,
public static void Register(HttpConfiguration config)
{
var jsonFormatter = config.Formatters.OfType<JsonMediaTypeFormatter>().First();
var settings = jsonFormatter.SerializerSettings;
settings.Converters.Add(new IsoDateTimeConverter());
settings.Error += (sender, args) => Console.WriteLine("This event is fired ok");
}
If we send some JSON to the endpoint that looks like this
{
"userName": "User1",
"dateOfBirth": "jhdgjhjfg"
}
...the error event is fired in the Serializer settings and the endpoint is called. At this point, the DateOfBirth field is null and I don't have any context that a deserialization error has occurred
Reading the JSON.Net documentation, because Handled == false in the Error event arguments of the Settings object, an exception should be raised into the application code - this doesn't happen? Is there a setting I haven't configured correctly for this?
How can I get context within the action so that I know a value was specified for a field and couldn't be deserialized? Even global behaviour would be fine, as long as I know this has happened and can return a 400.
UPDATE:
We can use a filter to check the Model state, then check the Model State errors for exceptions of type JsonReaderException. This lets you return a 400 with a list of violating fields
public class CheckJsonExceptionModelStateAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(HttpActionContext actionContext)
{
if (actionContext.ModelState.IsValid)
{
return;
}
var fieldsInError = new List<string>();
foreach (var jsonException in
actionContext.ModelState.Keys.SelectMany(key => actionContext.ModelState[key].Errors)
.Select(error => error.Exception).OfType<JsonReaderException>())
{
Trace.TraceError(jsonException.Message);
fieldsInError.Add(jsonException.Path);
}
var apiError = new { ErrorMessages.BadRequestModel.Message, FieldsInError = new List<string>() };
foreach (var fieldError in fieldsInError)
{
apiError.FieldsInError.Add(fieldError);
}
actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.BadRequest, apiError);
}
}
You have multiple options. But first, you are getting no exception because the WebApi handles this exception. Bad news.
Good news, you can handle it in at least two ways; use the ModelState.IsValid property - in your case it will be false. You can access them in your post-method. When you remove the invalid dateOfBirth it is true ;-)
Or you can use an ActionFilterAttribute to put it on your methods for re-use purposes.
For example:
public async Task<IHttpActionResult> Create(UserModel user) {
if (!ModelState.IsValid) {
// ModelState.Keys // Get all error-keys
}
}
I am having some problems parsing my model in ASP.NET MVC API
This is my API controller:
public class UserController : ApiController
{
// Hent liste af personer
public IEnumerable<UserModel> Get()
{
return new UserModel[] { new UserModel(), new UserModel() };
}
// Hente enkelt person
public UserModel Get(int id)
{
return new UserModel();
}
// Opret person
[ValidationActionFilter]
public CreateUserRespose Post([FromBody]UserModel model)
{
CreateUserRespose rs = new CreateUserRespose();
return rs;
}
// Rediger person
public UserModel Put(int id, [FromBody]UserModel model)
{
return new UserModel();
}
// Slet person
public UserModel Delete(int id)
{
return new UserModel();
}
}
}
And the UserModel:
public class UserModel
{
[Required]
[StringLength(500)]
public String FristName { get; set; }
[Required]
[StringLength(500)]
public String LastName { get; set; }
[Required]
[StringLength(250)]
public String Email { get; set; }
[Required]
public String MatrikelId { get; set; }
}
When I call though Fiddler to the Post command with the following body
FirstName=Fistname MiddleName&LastName=SomeName&Email=email#email.us&MatrikelId=1234
Will the action Post be called, but the model is null, and ModelState.IsValid is true, the same happens if I send no data with the body!
What am I doing wrong here?
Update:
I have tryed sending the data as json instead
Fiddler:
User-Agent: Fiddler
Host: localhost:51268
Content-Length: 102
Content-type: application/json
{"FristName":"Kasper asdasd","LastName":"asdasdasd","Email":"asdaasd#asdasd.us","MatrikelId":"132456asd"}
But should the model state not be invalid when the model is null?
The ASP.NET Web API is using content negotiation process in order to decide which MediaTypeFormatter to use for deserializing the body of the request. For the typical POST request it will check for Accept and Content-Type headers. If none is present it will use the first MediaTypeFormatter on the list (by default it is JsonMediaTypeFormatter).
In your case Web API was unable to determine the proper MediaTypeFormatter. Adding a Content-Type header with value of application/x-www-form-urlencoded to the request should resolve the issue.
If you want to get more detailed knowledge regarding Formatters, Model Binding and Content Negotiation in ASP.NET Web API I would suggest following reading:
Designing Evolvable Web APIs with ASP.NET -> Chapter 8. Formatters and Model Binding (you should look very close at the entire book if you are interesed in learning ASP.NET Web API)
Everything you want to know about ASP.NET Web API content negotiation