I am posting an object to a WebApi method. I'm using PostAsJsonAsync to do this.
public async Task<HttpResponseMessage> PostAsync(string token, ServiceCall call)
{
var client = new HttpClient();
client.SetBearerToken(token);
var response = await client.PostAsJsonAsync(Uri + "id/nestedcall", call);
return response;
}
The object call that I'm passing is not null when I post it.
[HttpPost]
[Route("id/nestedcall")]
public async Task<IHttpActionResult> NestedCall([FromBody]ServiceCall call)
{
// call is null here
}
However it is null in my API method. I can't seem to work out why as all of the examples I've followed use this format.
Why isn't the call object being picked up by the web api?
Edit
Here is the ServiceCall object. It is in a separate class library and a reference is included in both the web application and the API.
public class ServiceCall
{
public ServiceCall(Service service, string grantType)
{
ClientId = service.Id;
ClientSecret = service.Secret;
Uri = service.Uri;
Scope = service.Scope;
GrantType = grantType;
}
public ServiceCall(string clientid, string clientsecret, string uri, string scope, string grantType)
{
ClientId = clientid;
ClientSecret = clientsecret;
Uri = uri;
Scope = scope;
GrantType = grantType;
}
public string ClientId { get; set; }
public string ClientSecret { get; set; }
public string Uri { get; set; }
public string Scope { get; set; }
public string GrantType { get; set; }
}
I have seen Object null in WebApi method after PostAsJsonAsync due to serialization.
Better to use PostAsync like below :
var obj = new MyClass()
{
MyProperty = 11
};
using (var client = new HttpClient())
{
string inputJson = Newtonsoft.Json.JsonConvert.SerializeObject(obj);
HttpContent inputContent = new StringContent(inputJson, Encoding.UTF8, "application/json");
HttpResponseMessage response1 = client.PostAsync("http://localhost:60909/api/home/Test", inputContent).Result;
if (response1.IsSuccessStatusCode)
{
}
}
Using Prefix Stackify I was able to diagnose that the serialiser was throwing an exception:
Newtonsoft.Json.JsonSerializationException: Unable to find a constructor to use for type Core.Models.ServiceCall. A class should either have a default constructor, one constructor with arguments or a constructor marked with the JsonConstructor attribute. Path 'ClientId', line 1, position 12.
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateNewObject
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize
However, very helpfully, rather than tell me that an exception occurred the controller simply gave me a null object.
As hinted by the exception the solution is to add a default constructor (or at least one the serialiser can understand).
public ServiceCall()
{
}
looks like the JSON serialization may be failing. BTW, remove that [FromBody] and try without it like below. PostAsJsonAsync method serializes the ServiceCall object to JSON and then sends the JSON payload in a POST request.
public async Task<IHttpActionResult> NestedCall(ServiceCall call)
{
// your code
}
I run into exactly the same problem and had to do this to solve it:
using (var client = new HttpClient())
{
client.SetBearerToken(token);
var content = new StringContent(JsonConvert.SerializeObject(call), Encoding.UTF8, "application/json");
var response = await client.PostAsJsonAsync(Uri + "id/nestedcall", content);
return response;
}
Related
Postman Post call Screenshot
Hi Below is my current code:
var url = "https://localhost:44332/token";
var login = new Login()
{
username = "test#gmail.com",
password = "Password#1",
grant_type = "password"
};
using (var client = new HttpClient())
{
httpResponseMessage = await client.PostAsJsonAsync(url, login);
if (httpResponseMessage.IsSuccessStatusCode)
{
var token = httpResponseMessage.Content.ReadAsStringAsync();
}
}
My error is that 400: Bad Request, whenever i make the API call.
If i use postman, its working,
The following is what i put in POSTMAN body:
"username=test#gmail.com&password=Password#1&grant_type=password"
Many Thanks in advance if anyone can correct me!
It looks like you're trying to get hte token from OAuth 2.0 authentications server. You shouldn't be posting JSON - it expects the data as form. It returns a JSON object with access token storen in property access_token - you probably will need to deserialize it as well.
using System.Net.Http.Json;
using System.Text.Json.Serialization;
var url = "https://localhost:44332/token";
var form = new Dictionary<string, string>
{
{"grant_type", "password"},
{"username","test#gmail.com#1"},
{"password", "Password#1"},
};
using (var client = new HttpClient())
{
var response = await client.PostAsync(url, new FormUrlEncodedContent(form));
if (response.IsSuccessStatusCode)
{
var token = await response.Content.ReadFromJsonAsync<Token>();
var accessToken = token.AccessToken;
}
}
class Token
{
[JsonPropertyName("access_token")]
public string AccessToken { get; set; }
[JsonPropertyName("token_type")]
public string TokenType { get; set; }
[JsonPropertyName("expires_in")]
public int ExpiresIn { get; set; }
[JsonPropertyName("refresh_token")]
public string RefreshToken { get; set; }
}
Do you pass these parameters by URL in postman? This form username=test#gmail.com&password=Password#1&grant_type=password looks like you use URL past parameters in postman.
Usually, in POST requests we pass parameters in the request body, not the URL.
Besides, a recommendation is not directly a HttpClient instance. If you use .NET Framework and create the HttpClient instance directly, cannot release the socket resource even if you disposable the HttpClient object. If you use .NET Core, you can inject an HttpClient or IHttpClientFactory.
Refers: Use IHttpClientFactory to implement resilient HTTP requests
I have a little program which should communicate with "Slack". In an older Version I used "Dictionary<string, string>" and then put them into UrlEncodedContent - which worked fine.
Now I am trying to create a Json-object, using Newtonsoft's Nuget-package and (in my opinion) formatting my object the way they say on their website.
Problem is, when I try to make a simple request, my program just runs to one specific line in the code(var response = await _httpClient.SendAsync(request);) and then it just ends. It doesn't throw an exception or display any kind of message, it simply ends on this line. I went through my code step by step while debugging, that's how I know it ends on exactly this line. And I just don't know why!
Now my code:
First, my object...
namespace BPS.Slack
{
public class JsonObject
{
//generally needed parameters
[JsonProperty("ok")]
public bool ok { get; set; }
[JsonProperty("error")]
public string error { get; set; }
[JsonProperty("channel")]
public string channel { get; set; }
[JsonProperty("token")]
private string token = "xoxp-MyToken";
[JsonProperty("as_user")]
public bool as_user = false;
[JsonProperty("username")]
public string username { get;set; }
//--------------------------------
//only needed for textmessages
[JsonProperty("text")]
public string text { get; set; }
//--------------------------------
//for posting messages with data attached
[JsonProperty("initial_comment")]
public string initial_comment { get; set; }
[JsonProperty("file")]
public string file { get; set; }
[JsonProperty("channels")]
public string channels { get; set; }
//--------------------------------
//for getting the latest message from a channel
[JsonProperty("count")]
public string count = "1";
[JsonProperty("unreads")]
public bool unreads = true;
}
}
now the client:
namespace BPS.Slack
{
public class BpsHttpClient
{
private readonly HttpClient _httpClient = new HttpClient { };
public Uri UriMethod { get; set; }
public BpsHttpClient(string webhookUrl)
{
UriMethod = new Uri(webhookUrl);
}
public async Task<HttpResponseMessage> UploadFileAsync(MultipartFormDataContent requestContent)
{
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, UriMethod);
request.Content = requestContent;
var response = await _httpClient.SendAsync(request);
return response;
}
}
}
and the main
namespace TestArea
{
class MainArea
{
public static void Main( string[] args)
{
try
{
Task.WhenAll(SendMessage());
}
catch(Exception ass)
{
Console.WriteLine(ass);
Console.ReadKey();
}
}
private static async Task SendMessage()
{
var client = new BpsHttpClient("https://slack.com/api/im.history");
JsonObject JO = new JsonObject();
JO.channel = "DCW21NBHD";
var Json = JsonConvert.SerializeObject(JO);
var StringJson = new StringContent(Json, Encoding.UTF8);
MultipartFormDataContent content = new MultipartFormDataContent();
content.Add(StringJson);
var Response = await client.UploadFileAsync(content);
string AnswerContent = await Response.Content.ReadAsStringAsync();
Console.WriteLine(AnswerContent);
Console.ReadKey();
}
}
}
I had the same problem in my older version, BUT only as I wanted to DEserialize an answer I got from Slack. It had to do with my object I tried do deserialize the answer into. But this time I can not figure out what's wrong. But, as I said, I do not have any experience with using serialized objects as Json-property to send requests... anyone has an idea what is wrong with my code?
EDIT: This problem is kinda solved. But there is a follow up problem.
Okay, I found out that the reason for the abprubt termination was the
Task.WhenAll(SendMessage());
it should be
Task.WaitAll(SendMessage()); Why??? Somebody said I should use WhenAll, but obviously it doesn't work properly in this case...
Now I get a response from Slack, but now a different problem has arisen. When I use this method:
public async Task<HttpResponseMessage> UploadFileAsync(MultipartFormDataContent requestContent)
{
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, UriMethod);
request.Content = requestContent;
var response = await _httpClient.SendAsync(request);
return response;
}
I allways get the answer:
{"ok":false,"error":"invalid_form_data"}
so I tried to explicitly tell it the 'mediaType', I tried "application/json" and others, but with all of them I get the same error. Here is the full method that calls the upper mehtod:
private static async Task SendMessage()
{
var client = new BpsHttpClient("https://slack.com/api/chat.postMessage");
JsonObject JO = new JsonObject();
JO.channel = "DCW21NBHD";
JO.text = "This is so much fun :D !";
var Json = JsonConvert.SerializeObject(JO, new JsonSerializerSettings { NullValueHandling = NullValueHandling.Ignore });
var StringJson = new StringContent(Json, Encoding.UTF8, "application/json");
var requestContent = new MultipartFormDataContent();
requestContent.Add(StringJson);
var Response = await client.UploadFileAsync(requestContent);
string AnswerContent = await Response.Content.ReadAsStringAsync();
}
When I use this method:
public async Task<HttpResponseMessage> SendMessageAsync(FormUrlEncodedContent content)
{
var response = await _httpClient.PostAsync(UriMethod, content);
return response;
}
so bascially I am passing "FormUrlEncodedContent" instead of "MultipartFormDataContent" in this, and then I get the response I want and can work wiht it. BUT this i of little use to me since I have to use "MultipartFormDataContent" to be able to send files with my requests.
Anyone have an idea what is failing here? Why does it not like the one content-type but the other one? I'd be gratefull for tipps and ideas!
You are serializing your object to Json and then adding it to a Multipart body, that's quite strange. Unless you're uploading binary data (eg Files), there is no need to use MultipartFormDataContent.
You are can directly post your JsonObject serialized as JSON:
public async Task<HttpResponseMessage> PostJsonAsync(StringContent content)
{
var response = await client.PostAsync(url, content);
return response;
}
var client = new BpsHttpClient("https://slack.com/api/im.history");
JsonObject JO = new JsonObject();
JO.channel = "DCW21NBHD";
var Json = JsonConvert.SerializeObject(JO);
var StringJson = new StringContent(Json, Encoding.UTF8);
var Response = await client.PostJsonAsync(content);
Also this is should be POST on the UploadFileAsync function.
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, UriMethod);
so I figured out that in the Main() the problem was this:
Task.WhenAll(SendMessage());
I should instead use:
Task.WaitAll(SendMessage());
Anyone who has more knowledge on this, please elaborate why!
I am doing an MVC 5 Application, and I am calling a API controller method that is in another Solution.
I am using HttpClient(). and I am calling PostAsJsonAsync with some parameters, an instance of a class.
It looks like this.
string apiUrl = "localhost:8080/api/";
ContactWF contactWF = new contactWF();
contactWF.contact_id=0;
contactWF.UserOrigin_id=20006
contactWF.ProcessState_id=2;
using (HttpClient client = new HttpClient())
{
client.BaseAddress = new Uri(apiUrl);
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.PostAsJsonAsync(apiUrl + "Contact/Method", contactWF);
if (response.IsSuccessStatusCode)
{
return response.Content.ReadAsAsync<int>().Result;
}
}
My API controller method is like this.
[ActionName("Method")]
[HttpGet]
public int Method([FromBody] ContactWF userwf)
{
return 10;
}
It Works fine...
My problem is when I try Serialized the parameter class instance
I replace line
HttpResponseMessage response = await client.PostAsJsonAsync(apiUrl + "Contact/Method", contactWF);
with this one
string jsonData = JsonConvert.SerializeObject(contactWF);
HttpResponseMessage response = client.PostAsJsonAsync("api/Contact/Method", jsonData).Result;
I've got an Error:405...
It looks like the Json string it is not recognize as a Parameter.
My Json string looks like this.
"{\"Contact_id\":0,\"Description\":null,\"ProcessState_id\":2,\"Type_id\":0,\"Object_id\":0,\"Parent_id\":null}"
that is ContactWD class converter to json.
What´s wrong?
Method PostAsJsonAsync serialize parameter object himself, so it serialized your json string again.
If you need serialize object himself for some reason, then use method HttpClient.PostAsync
string jsonData = JsonConvert.SerializeObject(contactWF);
var stringContent = new StringContent(jsonData, Encoding.UTF8, "application/json");
HttpResponseMessage response = await client.PostAsync("api/Filler/CountMensajeByUser", stringContent);
Change verb to HttpPost in your api controller
[ActionName("Method")]
[HttpPost]
public int Method([FromBody] ContactWF userwf)
{
return 10;
}
Update
You don't need to serialize object in PostAsJsonAsync
HttpResponseMessage response = client.PostAsJsonAsync("api/Contact/Method", contactWF).Result;
Take a look at sample code from microsoft
https://learn.microsoft.com/en-us/aspnet/core/mvc/controllers/testing
internal class NewIdeaDto
{
public NewIdeaDto(string name, string description, int sessionId)
{
Name = name;
Description = description;
SessionId = sessionId;
}
public string Name { get; set; }
public string Description { get; set; }
public int SessionId { get; set; }
}
//Arrange
var newIdea = new NewIdeaDto("Name", "", 1);
// Act
var response = await _client.PostAsJsonAsync("/api/ideas/create", newIdea);
// Assert
Assert.Equal(HttpStatusCode.BadRequest, response.StatusCode);
I have webforms asp and web api. In web forms I try send to web api object of class this way:
HttpClient client = HttpClientHeader("", login, ClassMd5Calc.CalculateMd5Hash(password));
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
UserTariff userTariff = new UserTariff();
userTariff.Login = "some value";
userTariff.Password = "some value";
userTariff.TariffName = "some value";
var json = new JavaScriptSerializer().Serialize(userTariff);
StringContent content = new StringContent(json);
content.Headers.ContentType = new MediaTypeHeaderValue("text/json");
HttpResponseMessage response = client.PostAsync("api/ChangeTariff/", content).Result;
This is my class (exist in data contract solution, so both project are use this class).
[Serializable]
public class UserTariff
{
public String Login { get; set; }
public String Password { get; set; }
public String TariffName { get; set; }
public decimal Balance { get; set; }
}
My web api receive package, but all field are null. What's wrong? How it's fix?
public class ChangeTariffController : ApiController
{
public void Post([FromBody] UserTariff mes)
{
//mes exist, but his property are null: mes.Login=null; mes.Password=null and e.t.c. but need value: "some value"
UPDATE 1.
I also tryed this code, but it show same error:
var content = new ObjectContent<UserTariff>(new UserTariff(), new JsonMediaTypeFormatter());
content.Headers.ContentType = new MediaTypeHeaderValue("text/json");
HttpResponseMessage response = client.PostAsync("api/ChangeTariff/", content).Result;
You can set the object content instead of the string content and should be using json media type formatter. This should fix the null bound variable in web api.
Also, use the newton soft json lib to convert the object to json.
Hello I would like to call Web Api method from C# client by my body variable in web api controller is null all the time.
How to set it correct ?
client side:
IFileService imgService = new ImageServiceBll();
var image = System.Drawing.Image.FromFile(serverFile);
var dataImage = imgService.ImageToBase64(image, System.Drawing.Imaging.ImageFormat.Png);
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("http://site.local/");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
// HTTP POST
var data = new
{
imageData = dataImage,
version = version
};
HttpResponseMessage response = await client.PostAsJsonAsync("api/contenttool/SaveImage", data);
if (response.IsSuccessStatusCode)
{
Uri gizmoUrl = response.Headers.Location;
}
}
Server Side:
public class ContentToolController : ApiController
{
public IFileService FileService { get; set; }
// POST api/contenttool
public string SaveImage([FromBody]string data)
{
JObject jObject = JObject.Parse(data);
JObject version = (JObject)jObject["version"];
return "-OK-" + version;
}
}
I think it has more to do with the fact that you technically aren't passing in a string. You are passing in a JSON serialized string representation of an anonymous type, so the deserialization process in the Web Api is working against you. By the time your request gets to the controller and that method, it isn't a string anymore. Try changing your type on the SavImage method to be dynamic. Like this:
public string SavImage([FromBody]dynamic data)
{
JObject jObject = JObject.Parse(data);
JObject version = (JObject)jObject["version"];
return "-OK-" + version;
}
Unfortunately at that point you won't be able to use intellisense to get your properties out. You will have to get the data out of the dynamic type via a dictionary.
Dictionary<string, object> obj = JsonConvert.DeserializeObject<Dictionary<string, object>>(Convert.ToString(data));
Of course your other option would be to use an actual type that is shared between the client and the server. That would make this a bit easier.
The string value passed in the body probably needs to be prefixed with the = sign.