title: Validation of HTTPClient and HTTPRequest Code
body: <p>I am trying to send a request to Identity verification company. They are asking to send three headers. I added the headers like so:</p>
  
  <pre><code>                HttpClient client = new HttpClient();
                  client.BaseAddress = new Uri("https://api.test");
                  client.DefaultRequestHeaders.Accept.Add(new 
                  MediaTypeWithQualityHeaderValue("application/json"));//ACCEPT header
                  client.DefaultRequestHeaders.TryAddWithoutValidation("hmac-signature", Hmackey);
                  HttpRequestMessage request = new HttpRequestMessage();
                  request.Method = HttpMethod.Post;
  
                  request.Content = new StringContent(JSONFile, Encoding.UTF8,
                                      "application/json");
                  HttpResponseMessage response = client.SendAsync(request).Result;
                  string responseContent = await response.Content.ReadAsStringAsync();
  </code></pre>
  
  <p>I posted the same JSON file in SOAP UI and I got the response back, but when I send the same JSON file using my code above, I get below error:</p>
  
  <pre><code>{
      "responseHeader": {
          "tenantID": "V2321",
          "requestType": "PreciseIdOnly",
          "clientReferenceId": "PIDInitial-2312313",
          "expRequestId": "",
          "messageTime": "2020-06-09T17:17:49Z",
          "responseCode": "R0302",
          "responseType": "ERROR",
          "responseMessage": "The HMAC validation failed : Invalid Signature or no matching alias found."
      },
      "originalRequestData": null
  }
  </code></pre>
  
  <p>The only difference is that in my code, I have "/r/n" and "/". I can remove "/r/n", but cannot remove "/" because double codes are preceded by forward slash.</p>
  
  <p>Instead of calculating HMAC key, I got the HMAC key from SOAP UI from HTTP logs and put that in my code .  I still get the same error saying  "HMAC validation failed". I just want to make sure that does my code above looks right? I am supposed to add three headers like so:</p>
  
  <pre><code>Accept:application/json
  Content-Type:application/json
  hmac-signature:&lt;TheCalculatedHMACSignature&gt;
  </code></pre>
  
  <p>Does my code look right with these three headers. This is my first application where I am sending a request and I am thinking may be something in my code that is causing this error. I am not calculating HMAC key anymore. I am getting that key from SOAP UI Http logs and my  response from SOAP UI looks good.</p>
  
  <p>Any help in validating my code will be highly appreciated.</p>