Getting error while posting data to sql using .net Web API in xamarin.forms
StatusCode: 204, ReasonPhrase: 'No Content', Version: 1.1, Content: System.Net.Http.StreamContent, Headers:{Cache-Control: no-cache Pragma: no-cache Server: Microsoft-IIS/8.5 X-AspNet-Version: 4.0.30319 X-Powered-By: ASP.NET Access-Control-Allow-Headers: Content-Type Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS Date: Thu, 17 Mar 2016 08:32:28 GMT Expires: -1 }}
this is my code to post data
T returnResult = default(T);
HttpClient client = null;
try
{
client = new HttpClient();
client.BaseAddress = new Uri(HostName);
client.DefaultRequestHeaders.Add("Accept", "application/json");
client.Timeout = new TimeSpan(0, 0, 15);
HttpResponseMessage result = null;
StringContent data = null;
if (content != null)
// data = new StringContent(JsonConvert.SerializeObject(content), UTF8Encoding.UTF8, "application/json");
data = new StringContent(JsonConvert.SerializeObject(content), Encoding.UTF8, "application/json");
if (method == HttpMethod.Get)
result = await client.GetAsync(endpoint);
if (method == HttpMethod.Put)
result = await client.PutAsync(endpoint, data);
if (method == HttpMethod.Delete)
result = await client.DeleteAsync(endpoint);
if (method == HttpMethod.Post)
result = await client.PostAsync(endpoint, data);
if (result != null)
{
if (result.IsSuccessStatusCode
&& result.StatusCode == System.Net.HttpStatusCode.OK)
{
var json = result.Content.ReadAsStringAsync().Result;
returnResult = JsonConvert.DeserializeObject<T>(json);
}
}
where should be the problem ?. My API is working fine and it is enabled CORS
Here is an example of how I am using PostAsync in my code, I think the error 'No Content' is referring on you are not sending anything to the server maybe? I hope this example helps:
public async Task<bool> PostAppointmet(AppointmentEntity anAppointment)
{
try{
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Add("Authorization", "Bearer " + App.apiToken);
const string resourceUri = ApiBaseAddress + "/citas";
string postBody = JsonConvert.SerializeObject(anAppointment);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.PostAsync (resourceUri, new StringContent (postBody, Encoding.UTF8, "application/json"));
if (response.IsSuccessStatusCode) {
return true;
}
return false;
}
catch{
return false;
}
}
Where AppointmentEntity is my Model:
public class AppointmentEntity
{
public int doctor { get; set; }
public PatientEntity paciente { get; set; }
public DateEntity cita { get; set; }...
}
Try to use like this
var task = client.PostAsync(endpoint,content:data);
Related
I am trying to implement jwt token authentication in my web api. I have a front end app which is in angular 8. i want to save the token in cookie.how can i achieve this?? what will be the syntax for the subsequent call from the angular,if i save the token in cookie after login.
TokenValidationHandler
internal class TokenValidationHandler : DelegatingHandler
{
private static bool TryRetrieveToken(HttpRequestMessage request, out string token)
{
token = null;
IEnumerable<string> authzHeaders;
if (!request.Headers.TryGetValues("Authorization", out authzHeaders) || authzHeaders.Count() > 1)
{
return false;
}
var bearerToken = authzHeaders.ElementAt(0);
token = bearerToken.StartsWith("Bearer ") ? bearerToken.Substring(7) : bearerToken;
return true;
}
protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
HttpStatusCode statusCode;
string token;
//determine whether a jwt exists or not
if (!TryRetrieveToken(request, out token))
{
statusCode = HttpStatusCode.Unauthorized;
//allow requests with no token - whether a action method needs an authentication can be set with the claimsauthorization attribute
return base.SendAsync(request, cancellationToken);
}
try
{
const string sec = "401b09eab3c013d4ca54922bb802bec8fd5318192b0a75f201d8b3727429090fb337591abd3e44453b954555b7a0812e1081c39b740293f765eae731f5a65ed1";
var now = DateTime.UtcNow;
var securityKey = new Microsoft.IdentityModel.Tokens.SymmetricSecurityKey(System.Text.Encoding.Default.GetBytes(sec));
SecurityToken securityToken;
JwtSecurityTokenHandler handler = new JwtSecurityTokenHandler();
TokenValidationParameters validationParameters = new TokenValidationParameters()
{
ValidAudience = "http://localhost:50191",
ValidIssuer = "http://localhost:50191",
ValidateLifetime = true,
ValidateIssuerSigningKey = true,
LifetimeValidator = this.LifetimeValidator,
IssuerSigningKey = securityKey
};
//extract and assign the user of the jwt
Thread.CurrentPrincipal = handler.ValidateToken(token, validationParameters, out securityToken);
HttpContext.Current.User = handler.ValidateToken(token, validationParameters, out securityToken);
return base.SendAsync(request, cancellationToken);
}
catch (SecurityTokenValidationException e)
{
statusCode = HttpStatusCode.Unauthorized;
}
catch (Exception ex)
{
statusCode = HttpStatusCode.InternalServerError;
}
return Task<HttpResponseMessage>.Factory.StartNew(() => new HttpResponseMessage(statusCode){ });
}
public bool LifetimeValidator(DateTime? notBefore, DateTime? expires, SecurityToken securityToken, TokenValidationParameters validationParameters)
{
if (expires != null)
{
if (DateTime.UtcNow < expires) return true;
}
return false;
}
}
LoginController(will generate the token)
public class LoginController : ApiController
{
[HttpPost]
public IHttpActionResult Authenticate([FromBody] LoginRequest login)
{
var loginResponse = new LoginResponse { };
LoginRequest loginrequest = new LoginRequest { };
loginrequest.Username = login.Username.ToLower();
loginrequest.Password = login.Password;
IHttpActionResult response;
HttpResponseMessage responseMsg = new HttpResponseMessage();
bool isUsernamePasswordValid = false;
if(login != null)
isUsernamePasswordValid=loginrequest.Password=="pass" ? true:false;
// if credentials are valid
if (isUsernamePasswordValid)
{
string token = createToken(loginrequest.Username);
//return the token
return Ok<string>(token);
}
else
{
// if credentials are not valid send unauthorized status code in response
loginResponse.responseMsg.StatusCode = HttpStatusCode.Unauthorized;
response = ResponseMessage(loginResponse.responseMsg);
return response;
}
}
private string createToken(string username)
{
//Set issued at date
DateTime issuedAt = DateTime.UtcNow;
//set the time when it expires
DateTime expires = DateTime.UtcNow.AddSeconds(30);
//http://stackoverflow.com/questions/18223868/how-to-encrypt-jwt-security-token
var tokenHandler = new JwtSecurityTokenHandler();
//create a identity and add claims to the user which we want to log in
ClaimsIdentity claimsIdentity = new ClaimsIdentity(new[]
{
new Claim(ClaimTypes.Name, username)
});
const string sec = "401b09eab3c013d4ca54922bb802bec8fd5318192b0a75f201d8b3727429090fb337591abd3e44453b954555b7a0812e1081c39b740293f765eae731f5a65ed1";
var now = DateTime.UtcNow;
var securityKey = new Microsoft.IdentityModel.Tokens.SymmetricSecurityKey(System.Text.Encoding.Default.GetBytes(sec));
var signingCredentials = new Microsoft.IdentityModel.Tokens.SigningCredentials(securityKey,Microsoft.IdentityModel.Tokens.SecurityAlgorithms.HmacSha256Signature);
//create the jwt
var token =
(JwtSecurityToken)
tokenHandler.CreateJwtSecurityToken(issuer:"http://localhost:50191",audience:"http://localhost:50191",
subject: claimsIdentity, notBefore: issuedAt, expires: expires, signingCredentials: signingCredentials);
var tokenString = tokenHandler.WriteToken(token);
return tokenString;
}
}
Firstly, the httponly cookie cannot be accessed from JavaScript.
Secondly, please refer to the code below to return the cookie along with the response.
private HttpResponseMessage setTokenCookie(LoginResponse response)
{
var responseMessage = Request.CreateResponse(HttpStatusCode.OK, response);
var cookie = new CookieHeaderValue("token", response.Token)
{
Expires = DateTimeOffset.Now.AddDays(7),
HttpOnly = true
};
responseMessage.Headers.AddCookies(new CookieHeaderValue[] { cookie });
return responseMessage;
}
You can use the function mentioned above in your controller action method as shown below to return the cookie.
var responseWithCookie = setTokenCookie(response);
return ResponseMessage(responseWithCookie);
I've assumed that LoginResponse class has Token property.
I have a xamarin app that pull data from a webAPI. I check api address so many times and i am sure it is correct. When i debug my code i have 404 not found error from server. However when i copy and paste the URL to browser i have expected result. I couldn't figure out why my app return 404.
My Method:
public async Task<ICustomerType> GetById(int id)
{
string _token;
if (App.Current.Properties.ContainsKey("token"))
{
_token = (string)App.Current.Properties["token"];
}
else
{ _token = null; }
var webApiResponse =
_connector.PostAsync(
"api/Customer/get/id/" + id,
string.Empty, _token).Result;
var response = webApiResponse.Result.ToString();
var jObjectResponse = JObject.Parse(response);
ICustomerType customerTypeObj = null;
return customerTypeObj;
}
My bridge method to HttpClient's PostAsync method:
private async Task<TResponse> PostAsync(string requestPath, string
jsonContent, bool getToken, string token)
{
HttpClient client = new HttpClient();
client.BaseAddress = new Uri(_apiUrl);
client.DefaultRequestHeaders.Accept.Clear();
var contentType = new MediaTypeWithQualityHeaderValue("application/json");
client.DefaultRequestHeaders.Accept.Add(contentType);
if (getToken)
{
token = GetApiTokenAsync().Result;
}
if (!string.IsNullOrEmpty(token))
{
client.DefaultRequestHeaders.Add("Authorization", "Bearer " + token);
}
var httpContent = new StringContent(jsonContent, Encoding.UTF8, "application/json");
var response = client.PostAsync(requestPath, httpContent).Result;
var jsonData = await response.Content.ReadAsStringAsync();
return JsonConvert.DeserializeObject<TResponse>(jsonData);
}
Token: Correct
API Url: Correct(I check "/" signs from debug output.They are well placed. My Api like:
https://MyApi.net/api/Personel/get/id/1)
My Error:
response {StatusCode: 404, ReasonPhrase: 'Not Found', Version: 1.1, Content: System.Net.Http.StreamContent, Headers: { Request-Context:
appId=cid-v1:Some_String Server: Kestrel
Strict-Transport-Security: max-age=Some_Int Set-Cookie:
ARRAffinity=Some_String;Path=/;HttpOnly;Domain=MyDomain Date: Mon,
09 Jul 2018 07:54:19 GMT X-Powered-By: ASP.NET Content-Length: 0
}} System.Net.Http.HttpResponseMessage
your method verb in API is "GET" but you used "POST" in the client So in browser works because browser call "GET", but in the client doesn't work.
instead of :
var webApiResponse =
_connector.PostAsync(
"api/Customer/get/id/" + id,
string.Empty, _token).Result;
use :
var webApiResponse =
_connector.GetAsync(
"api/Customer/get/id/" + id,
string.Empty, _token).Result;
Hi I am just learning Xamarin android development and I just want to CRUD operation but I am stuck that I am unable to get any response from webapi. I have tested my api using SOAPUI and response is ok from that.
[HttpPost]
public HttpResponseMessage CreateEmpAttandance(string value)
{
if (value != "1234")
{
string json = #"{ data: 'Emp Code is not valid.'}";
var jObject = JObject.Parse(json);
var response = Request.CreateResponse(HttpStatusCode.OK);
response.Content = new StringContent(jObject.ToString(), System.Text.Encoding.UTF8, "application/json");
return response;
}
else
{
string json = #"{ data: 'data save sucessfully.'}";
var jObject = JObject.Parse(json);
var response = Request.CreateResponse(HttpStatusCode.OK);
response.Content = new StringContent(jObject.ToString(), System.Text.Encoding.UTF8, "application/json");
return response;
}
}
this is api code and below is my android application code but I am getting null response exception.
public async Task SaveTodoItemAsync(string EmpCode)
{
try
{
string url = "http://192.168.1.9/attandanceapi/api/attandance?value=12132";
var uri = new Uri(string.Format(url));
var json = JsonConvert.SerializeObject(EmpCode);
var content = new StringContent(EmpCode, Encoding.UTF8, "application/json");
HttpResponseMessage response = null;
response = await client.PostAsync(url, content);
var responses = response;
}
catch (Exception ex)
{
var w = ex.ToString();
}
}
I think we have problem here. You are trying to create content from string not from Json.
var content = new StringContent(EmpCode, Encoding.UTF8, "application/json");
try this:
var content = new StringContent(json, Encoding.UTF8, "application/json");
Edit:
I cannot see your default headers so if you don't have them - just add.
client.DefaultRequestHeaders.Add("Accept", "application/json");
I have an APIController Method as below. Basically I need to validate an API response. So it's an API call within an API call.
public class DCController : ApiController
{
[HttpPost]
public HttpResponseMessage SampleMethod(string url)
{
var uri = new Uri(url);
var baseAddress = uri.GetLeftPart(System.UriPartial.Authority);
var apiAddress = url.Replace(baseAddress + "/", "");
var responseString = string.Empty;
using (var client = new HttpClient())
{
client.BaseAddress = new Uri(baseAddress);
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var response = client.GetAsync(apiAddress).Result;
if (response.IsSuccessStatusCode)
{
responseString = response.Content.ReadAsStringAsync().Result;
}
}
if (!string.IsNullOrEmpty(responseString) && responseString.ToString().Validate())
{
return Request.CreateResponse(HttpStatusCode.OK, "Validated");
}
else
{
return Request.CreateErrorResponse(HttpStatusCode.BadRequest, "Invalid");
}
}
Issue:
1. Request object is null in the return lines.
2. If i try creating a request object -
var request = new HttpRequestMessage();
It throws below error:
An exception of type 'System.InvalidOperationException' occurred in
System.Web.Http.dll but was not handled in user code
Additional information: The request does not have an associated
configuration object or the provided configuration was null.
Not sure what settings I need to add. I am relatively new to working with APIs. Any help is appreciated.
I could get it working by below code -
[HttpPost]
public HttpResponseMessage Get(string url)
{
string responseString = GetWebApiData(url); //Extracted the method
HttpResponseMessage response = new HttpResponseMessage();
if (!string.IsNullOrEmpty(responseString) && responseString.ToString().Validate())
{
response.ReasonPhrase = "Valid";
response.StatusCode = HttpStatusCode.OK;
}
else
{
response.ReasonPhrase = "Invalid";
response.StatusCode = HttpStatusCode.BadRequest;
}
return response;
}
I want to send one pre request to my server before send every request. From that pre request I will receive the token from my server and than I have to add that token into all the request. This is the process.
I have try with some methods to achieve this. But I am facing one problem. That is, When I try to send pre request, it is processing with the current request. That mean both request going parallel.
I want to send pre request first and parse the response. After parsing the pre request response only I want to send that another request. But first request not waiting for the pre request response. Please let me any way to send pre request before all the request.
This is my code:
ViewModel:
`public class ListExampleViewModel
{
SecurityToken sToken = null;
public ListExampleViewModel()
{
GlobalConstants.isGetToken = true;
var listResults = REQ_RESP.postAndGetResponse((new ListService().GetList("xx","xxx")));
listResults.Subscribe(x =>
{
Console.WriteLine("\n\n..................................2");
Console.WriteLine("Received Response==>" + x);
});
}
}`
Constant Class for Request and Response:
`public class REQ_RESP
{
private static string receivedAction = "";
private static string receivedPostDate = "";
public static IObservable<string> postAndGetResponse(String postData)
{
if (GlobalConstants.isGetToken)
{
//Pre Request for every reusest
receivedPostDate = postData;
GlobalConstants.isGetToken = false;
getServerTokenMethod();
postData = receivedPostDate;
}
HttpWebRequest serviceRequest =
(HttpWebRequest)WebRequest.Create(new Uri(Constants.SERVICE_URI));
var fetchRequestStream =
Observable.FromAsyncPattern<Stream>(serviceRequest.BeginGetRequestStream,
serviceRequest.EndGetRequestStream);
var fetchResponse =
Observable.FromAsyncPattern<WebResponse>(serviceRequest.BeginGetResponse,
serviceRequest.EndGetResponse);
Func<Stream, IObservable<HttpWebResponse>> postDataAndFetchResponse = st =>
{
using (var writer = new StreamWriter(st) as StreamWriter)
{
writer.Write(postData);
writer.Close();
}
return fetchResponse().Select(rp => (HttpWebResponse)rp);
};
Func<HttpWebResponse, IObservable<string>> fetchResult = rp =>
{
if (rp.StatusCode == HttpStatusCode.OK)
{
using (var reader = new StreamReader(rp.GetResponseStream()))
{
string result = reader.ReadToEnd();
reader.Close();
rp.GetResponseStream().Close();
XDocument xdoc = XDocument.Parse(result);
Console.WriteLine(xdoc);
return Observable.Return<string>(result);
}
}
else
{
var msg = "HttpStatusCode == " + rp.StatusCode.ToString();
var ex = new System.Net.WebException(msg,
WebExceptionStatus.ReceiveFailure);
return Observable.Throw<string>(ex);
}
};
return
from st in fetchRequestStream()
from rp in postDataAndFetchResponse(st)
from str in fetchResult(rp)
select str;
}
public static void getServerTokenMethod()
{
SecurityToken token = new SecurityToken();
var getTokenResults = REQ_RESP.postAndGetResponse((new ServerToken().GetServerToken()));
getTokenResults.Subscribe(x =>
{
ServerToken serverToken = new ServerToken();
ServiceModel sm = new ServiceModel();
//Parsing Response
serverToken = extract(x, sm);
if (!(string.IsNullOrEmpty(sm.NetErrorCode)))
{
MessageBox.Show("Show Error Message");
}
else
{
Console.WriteLine("\n\n..................................1");
Console.WriteLine("\n\nserverToken.token==>" + serverToken.token);
Console.WriteLine("\n\nserverToken.pk==>" + serverToken.pk);
}
},
ex =>
{
MessageBox.Show("Exception = " + ex.Message);
},
() =>
{
Console.WriteLine("End of Process.. Releaseing all Resources used.");
});
}
}`
Here's couple options:
You could replace the Reactive Extensions model with a simpler async/await -model for the web requests using HttpClient (you also need Microsoft.Bcl.Async in WP7). With HttpClient your code would end up looking like this:
Request and Response:
public static async Task<string> postAndGetResponse(String postData)
{
if (GlobalConstants.isGetToken)
{
//Pre Request for every reusest
await getServerTokenMethod();
}
var client = new HttpClient();
var postMessage = new HttpRequestMessage(HttpMethod.Post, new Uri(Constants.SERVICE_URI));
var postResult = await client.SendAsync(postMessage);
var stringResult = await postResult.Content.ReadAsStringAsync();
return stringResult;
}
Viewmodel:
public class ListExampleViewModel
{
SecurityToken sToken = null;
public ListExampleViewModel()
{
GetData();
}
public async void GetData()
{
GlobalConstants.isGetToken = true;
var listResults = await REQ_RESP.postAndGetResponse("postData");
}
}
Another option is, if you want to continue using Reactive Extensions, to look at RX's Concat-method. With it you could chain the token request and the actual web request: https://stackoverflow.com/a/6754558/66988