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Need help to find where does API takes data from in ASP.NET MVC

I am a begginer and i work in a MVC project which I cant understand it well yet.
I can't understand where does the API takes data from when I try to connect in Login Screen.
It doesn't use Entity Framework and there isn't a json with the data.
When I enter Id and Pass it calls an API (GetAPIResponse) which somehow finds that is correct.
Need help to understand the code and the logic behind it.
LoginBL class contains:
public bool IsAuthenticated(LoginEntity user)
{
string url = string.Empty;
string callType = string.Empty;
string server = string.Empty;
try
{
// get URL, Call type, Server from config file
url = ConfigurationManager.AppSettings["login_url"].ToString();
callType = ConfigurationManager.AppSettings["calltype"].ToString();
server = ConfigurationManager.AppSettings["server"].ToString();
// Encrypt password
string password = Scrambler.GenerateMD5Hash(user.Password);
// Prepare content for the POST request
string content = #"calltype=" + callType + "&server=" + server + "&user=" + user.UserName + "&pass=" + password + "";
Debug.WriteLine("Callcenter login url: " + content);
HttpResponseMessage json_list = ApiCallBL.GetAPIResponse(url, content);
LoginResponseEntity obj = new LoginResponseEntity();
obj = JsonConvert.DeserializeObject<LoginResponseEntity>(json_list.Content.ReadAsStringAsync().Result);
Debug.WriteLine(callType + " Response: " + json_list.Content.ReadAsStringAsync().Result);
//if API resultCode return 0 then user details and token save in session for further use
if (obj.ResultCode == 0)
{
int restrict = obj.UserInfo.RestrictCallType.HasValue ?
obj.UserInfo.RestrictCallType.Value : 0;
HttpContext.Current.Session["user_id"] = obj.UserInfo.usr_id;
HttpContext.Current.Session["user_name"] = obj.UserInfo.usr_username;
HttpContext.Current.Session["user_group_id"] = obj.UserInfo.UserGroupID;
HttpContext.Current.Session["groupid"] = obj.UserInfo.groupid;
HttpContext.Current.Session["token"] = obj.Token;
HttpContext.Current.Session["web_server_url"] = obj.ServerInfo.web_server_url;
HttpContext.Current.Session["centerX"] = obj.ServerInfo.DefaultGeoX;
HttpContext.Current.Session["centerY"] = obj.ServerInfo.DefaultGeoY;
HttpContext.Current.Session["dateFormat"] = obj.ServerInfo.dateFormat;
HttpContext.Current.Session["currency"] = obj.ServerInfo.currency;
HttpContext.Current.Session["customer_img"] = obj.ServerInfo.customer_img;
HttpContext.Current.Session["groups"] = obj.groups;
HttpContext.Current.Session["restrict_call_type"] = restrict ;
Debug.WriteLine("obj.UserInfo.UserGroupID " + obj.UserInfo.UserGroupID);
Debug.WriteLine("obj.UserInfo.groups " + obj.groups);
//HttpContext.Current.Session["defaultLanguage"] = obj.ServerInfo.defaultLanguage;
HttpCookie cookie = new HttpCookie("Login");
// if remember me checked then user name and password stored in cookie else cookes is expired
if (user.RememberMe)
{
cookie.Values.Add("user_name", obj.UserInfo.usr_username);
cookie.Values.Add("pwd", user.Password);
cookie.Expires = DateTime.Now.AddDays(15);
HttpContext.Current.Response.Cookies.Add(cookie);
}
else
{
cookie.Expires = DateTime.Now.AddDays(-1);
HttpContext.Current.Response.Cookies.Add(cookie);
}
return true;
}
else
{
//ResultCode -5 :Invalid Login ,-1:Database Error ,-2:Server Error ,-3:Invalid Parameter specified ,-4:Invalid Token
return false;
}
}
catch
{
throw;
}
finally
{
url = string.Empty;
callType = string.Empty;
server = string.Empty;
}
}
Okay here after converts pass to MD5 creates a "string content" with the information given.
Then in next line (HttpResponseMessage json_list = ApiCallBL.GetAPIResponse(url, content);) calls the API with the url and content as parameters where it finds if the data exists.
API code:
public static HttpResponseMessage GetAPIResponse(string url, string content)
{
StringBuilder traceLog = null;
HttpContent httpContent = null;
try
{
traceLog = new StringBuilder();
traceLog.AppendLine("Start: BusinessLayer getAPIResponse() Request Data:- " + DateTime.Now + "URL = " + url + "&content = " + httpContent);
using (HttpClient client = new HttpClient())
{
httpContent = new StringContent(content);
httpContent.Headers.ContentType = new MediaTypeHeaderValue("application/x-www-form-urlencoded");
var resp = client.PostAsync(url, httpContent).Result;
Debug.WriteLine("resp: " + resp.Content.ReadAsStringAsync().Result);
traceLog.AppendLine("End: BusinessLayer getAPIResponse() call completed HttpResponseMessage received");
return resp;
}
}
catch
{
throw;
}
finally
{
traceLog = null;
httpContent.Dispose();
url = string.Empty;
content = string.Empty;
}
}
In the following line, console prints the result that I cant understand where it cames from (Debug.WriteLine("resp: " + resp.Content.ReadAsStringAsync().Result);)
Sorry for the confusion , I am in my first job with zero work experience and I am called to learn how this works alone without proper education on ASP.NET from them.

You will not go very far without debbugger. Learn how to debug in Visual Studio (YouTube tutorials might be fastest way). Place debug points along critical points in code (for example moment when client sends and receives response is line var resp = client.PostAsync...) and check variables.
Url for API server is actually defined in the line
url = ConfigurationManager.AppSettings["login_url"].ToString();
ConfigurationManager means Web.config file, check it's appSettings section for login_url entry, there is your url.
Btw, using (HttpClient client = new HttpClient()) is not a good way to use a HttpClient and will lead to port exhaustion. It's ok for small number of requests, but for larger ones you must reuse it, or use HttpClientFactory (for .NET Core).

C# Sending Cookies with Post Request

I want to sign in to youtube with post request. I used xNet for HttpRequest.
I wrote following codes:
static void Main(string[] args)
{
string url = "https://accounts.google.com/_/signin/sl/lookup?hl=en&_reqid=55174&rt=j";
HttpClass httpClass = new HttpClass();;
httpClass.PostRequestAsync(url, "username", "password");
}
class HttpClass {
public async Task PostRequestAsync(string url, string account, string pass)
{
xNet.HttpRequest http = new xNet.HttpRequest();
http.Cookies = new CookieDictionary();
string type = "application/x-www-form-urlencoded;charset=utf-8";
string query =
"continue=https%3A%2F%2Fwww.youtube.com%2Fsignin%3Ffeature%3Dsign_in_button%26action_handle_signin%3Dtrue%26app%3Ddesktop%26next%3D%252F%26hl%3Den&service=youtube&hl=en&f.req=%5B%22" + account + "%22%2C%22AEThLlxFJqXTI-dLw8jxU_Lw8c4Qtpc4DAAeEE1rpkbEUFqwwK1U86bZEzsWmZKM5IjRccPvbYTLgb0yonB3vputyMTNm-8YcGqbe_GeaB6RHFJImp_gZ-y0jFv4nduPGxM-zpJX8BahbDlIyeY2sP8-puVe3W1iwKX3rGcSFGMevHHK-ByNEUY%22%2C%5B%5D%2Cnull%2C%22TR%22%2Cnull%2Cnull%2C2%2Cfalse%2Ctrue%2C%5Bnull%2Cnull%2C%5B2%2C1%2Cnull%2C1%2C%22https%3A%2F%2Faccounts.google.com%2FServiceLogin%3Fuilel%3D3%26passive%3Dtrue%26service%3Dyoutube%26continue%3Dhttps%253A%252F%252Fwww.youtube.com%252Fsignin%253Ffeature%253Dsign_in_button%2526action_handle_signin%253Dtrue%2526app%253Ddesktop%2526next%253D%25252F%2526hl%253Den%26hl%3Den%22%2Cnull%2C%5B%5D%2C4%2C%5B%5D%2C%22GlifWebSignIn%22%5D%2C1%2C%5Bnull%2Cnull%2C%5B%5D%5D%2Cnull%2Cnull%2Cnull%2Ctrue%5D%2C%22" + account + "%22%5D&bgRequest=%5B%22identifier%22%2C%22!Pj2lPRxCiup4YICaVSxEHyFXdsNE5lECAAAAQ1IAAAAbCgAW9I8p8C1f10xg_NjCyA99rybP30APm5kBCr5B19mb-UkpwTj1ZsyybospA0TSjuUTuJeCHmkiRqKfhHxRE1CV0Yd7nifpK8VCTMNnmUMrl4-anneYlV-Bs3NQESEmJTEcxBOjvbo_tXSasO8KbZopdTxzUHm-qBGOQRTUZM4Hw6x-1HJdLoCQ2bi4FoAhbsWEt6paR0K4neYHS1kdxewjDKefWWCQ__O3C71yOjm6p0S1rjNUEM0ak9V8N2CcnIFYQ77b1B98nHCZmgMr81YtgAOF8ClSb4ZV8AiUc96rC1rvMV2RIvW54RUgsJwWHXBx0nid8tRMdUmzCTymoa-_at7qE1nJL8SMAU9WEnGOs0u2xKlBKGsjNgnqhligTDBDPnp7%22%5D&azt=AFoagUUuZ6teJ3APaa8f6ly_olQZHdGWBg%3A1525177142108&cookiesDisabled=false&deviceinfo=%5Bnull%2Cnull%2Cnull%2C%5B%5D%2Cnull%2C%22TR%22%2Cnull%2Cnull%2C%5B%5D%2C%22GlifWebSignIn%22%2Cnull%2C%5Bnull%2Cnull%2C%5B%5D%5D%5D&gmscoreversion=undefined&checkConnection=youtube%3A288%3A1&checkedDomains=youtube&pstMsg=1&";
string html;
html = http.Post(url, query, type).ToString();
htmlTest(html);
type = "application/x-www-form-urlencoded";
query =
account +
"&continue=https%3A%2F%2Fwww.youtube.com%2Fsignin%3Ffeature%3Dsign_in_button%26action_handle_signin%3Dtrue%26app%3Ddesktop%26next%3D%252F%26hl%3Den&password=" +
pass + "&ca=&ct=";
http.Cookies = new CookieDictionary();
html = http.Post(url, query, type).ToString();
htmlTest(html);
}
public void htmlTest(string html)
{
File.WriteAllText("a.html", html);
Process.Start("a.html");
}
}
Response is:
)]}' [[["er",null,null,null,["gf.rrerr",1,"https://support.google.com/accounts/answer/61416?hl\u003den"] ,null,"gf.rrerr"] ,["e",2,null,null,149] ]]
The given link "https://support.google.com/accounts/answer/61416?hl\u003den" is says you must to open your cache data. I think I need to pass cookies with post but How can I pass cookies with post request?

Try to use cookíe with code
request.Cookies = new CookieDictionary()
{
{"ggg", "hhh"}
};

Send Push Notification from a device via Azure NotificationHub REST Api

I am trying to send a push notification from an iOS device (iPhone) via Azure NotificationHub REST Api. I am attempting this from a Xamarin.iOS solution following the Azure documentation I found online.
Response returns following info:
Error: '50002: Provider Internal Error'
Status code: 500
Code used to invoke NotificationHub REST Api (from iOS client app):
var hubUtil = new NotificationHubUtility("Endpoint=sb://company-name.servicebus.windows.net/;SharedAccessKeyName=DefaultFullSharedAccessSignature;SharedAccessKey=00000000000000011111111111111122222222222222");
hubUtil.SendNotificationMessage("This is a TEST Notification!").ConfigureAwait(false);
public class NotificationHubUtility
{
public string Endpoint { get; private set; }
public string SasKeyName { get; private set; }
public string SasKeyValue { get; private set; }
public string HubName { get; private set; }
public string ApiVersion { get; private set; }
public NotificationHubUtility(string connectionString)
{
//Parse Connectionstring
string[] parts = connectionString.Split(new char[] {';'});
for (int i = 0; i < parts.Length; i++)
{
if (parts[i].StartsWith("Endpoint", StringComparison.CurrentCulture))
Endpoint = "https" + parts[i].Substring(11);
if (parts[i].StartsWith("SharedAccessKeyName", StringComparison.CurrentCulture))
SasKeyName = parts[i].Substring(20);
if (parts[i].StartsWith("SharedAccessKey", StringComparison.CurrentCulture))
SasKeyValue = parts[i].Substring(16);
}
HubName = "my-hub";
ApiVersion = "?api-version=2014-09-01";
}
public string GetSaSToken(string uri, int minUntilExpire)
{
string targetUri = Uri.EscapeDataString(uri.ToLower()).ToLower();
// Add an expiration in seconds to it.
long expiresOnDate = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
expiresOnDate += minUntilExpire * 60 * 1000;
long expires_seconds = expiresOnDate / 1000;
var toSign = targetUri + "\n" + expires_seconds;
// Generate a HMAC-SHA256 hash or the uri and expiration using your secret key.
IMacAlgorithmProvider hasher = WinRTCrypto.MacAlgorithmProvider.OpenAlgorithm(MacAlgorithm.HmacSha256);
var messageBuffer = WinRTCrypto.CryptographicBuffer.ConvertStringToBinary(toSign, Encoding.UTF8);
var keyBuffer = WinRTCrypto.CryptographicBuffer.ConvertStringToBinary(SasKeyValue, Encoding.UTF8);
var hmacKey = hasher.CreateKey(keyBuffer);
var signedMessage = WinRTCrypto.CryptographicEngine.Sign(hmacKey, messageBuffer);
string signature = Uri.EscapeDataString(WinRTCrypto.CryptographicBuffer.EncodeToBase64String(signedMessage));
var token = "SharedAccessSignature sig=" + signature + "&se=" + expires_seconds + "&skn=" + SasKeyName + "&sr=" + targetUri;
return token;
}
public async Task SendNotificationMessage(string message)
{
try
{
// basic http client (if needed)
var httpClient = new HttpClient();
httpClient.MaxResponseContentBufferSize = 1024000;
var notificationPayload = "{\"aps\":{\"alert\":\"" + message + "\"}}";
var notificationHubUrl = $"{Endpoint}{HubName}/messages/{ApiVersion}";
var authToken = GetSaSToken(notificationHubUrl, 10);
var request = new HttpRequestMessage(HttpMethod.Post, notificationHubUrl);
//request.Headers.Add("Content-Type", "application/json;charset=utf-8");
request.Headers.Add("ServiceBusNotification-Format", "apple");
request.Headers.Add("ServiceBusNotification-Apns-Expiry", DateTime.UtcNow.AddYears(1).ToString("YYYY-MM-DDThh:mmTZD"));
request.Headers.Add("Authorization", authToken);
var requestBody = new StringContent(notificationPayload, Encoding.UTF8, "application/json");
request.Content = requestBody;
var response = await httpClient.SendAsync(request, HttpCompletionOption.ResponseContentRead);
}
catch (Exception ex)
{
Console.Error.WriteLine(#"ERROR - Sending Notification {0}", ex.Message);
}
}
}
Example of Connection String:
Endpoint=sb://company-name.servicebus.windows.net/;SharedAccessKeyName=DefaultFullSharedAccessSignature;SharedAccessKey=00000000000000011111111111111122222222222222
Environment and Assumptions:
Xamarin.iOS solution using C#
Using PCLCrypto library for encryption
I am attempting to recreate the solution demonstrated in an Example in Azure examples github repo but using Xamarin.iOS
The connection string is taken directly from Azure portal
The code for generating SaS token is adapted from Azure NotificationHub REST Api Documentation
Notification hub works, I am able to send a test push notification through the hub UI and i see it come in on the device
What am I missing here? I wasn't able to find much relevant documentation for this error online. Any help would be greatly appreciated.
Update with Fix:
The following 2 changes to the code above fixed the issue for me:
Changed
ApiVersion = "?api-version=2014-09-01";
to
ApiVersion = "?api-version=2016-07";
Changed
request.Headers.Add("ServiceBusNotification-Apns-Expiry", DateTime.UtcNow.AddYears(1).ToString("YYYY-MM-DDThh:mmTZD"));
to
request.Headers.Add("ServiceBusNotification-Apns-Expiry", DateTime.UtcNow.AddYears(1).ToString("yyyy-MM-ddTHH:mm:sszzz"));

The Api Version 2014-09-01 is not correct. Please use 2016-07 as the Api version and you should be good.
Thanks
Sohrab

I've figured out the issue(s):
+1 to Sohrab for pointing out the Api Version, I updated it to ApiVersion = "?api-version=2016-07";
There was an error in the ServiceBusNotification-Apns-Expiry header value format, the date was not being correctly formatted to string. Corrected format string is this ToString("yyyy-MM-ddTHH:mm:sszzz")

ASP.NET Web APi - Passing an object as parameter

MakeUser method in the User controller for creating a username and password.
[HttpGet]
public string MakeUser(UserParameters p)
{
const string chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
string pass = "";
Random r = new Random();
for (int i = 0; i < p.Number; i++)
{
pass += chars[r.Next(0, 62)];
}
string firstTwoo = p.Name.Substring(0, 2);
string firstThree = p.Surname.Substring(0, 3);
return "Your username is: " + firstTwoo + firstThree + "\nYour password is: " + pass;
}
UserParameter class for sending the parameters as an object.
public class UserParameters
{
public int Number { get; set; }
public string Name { get; set; }
public string Surname { get; set; }
}
RunAsync method in console client. Can i pass an object with Get method? If yes what is my mistake here? Thank you!
static async Task RunAsync()
{
using (var client = new HttpClient())
{
var p = new UserParameters();
Console.Write("Your username: ");
p.Name = Console.ReadLine();
Console.Write("Your surname: ");
p.Surname = Console.ReadLine();
Console.Write("Please type a number between 5 and 10: ");
p.Number = int.Parse(Console.ReadLine());
client.BaseAddress = new Uri("http://localhost:4688/");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
//HTTP GET
HttpResponseMessage response = await client.GetAsync("api/user?p=" + p);
if (response.IsSuccessStatusCode)
{
var result = await response.Content.ReadAsAsync<UserParameters>();
Console.WriteLine("\n*****************************\n\n" + result);
}
}
}

GET requests don't support you passing objects in this way. The only option is to do it as a query string param as others have already demonstrated. From a design perspective, since you are creating a new resource it makes much more sense for this to be a POST or PUT request which both allow for an actual payload to be sent along with the request.
[HttpPost]
public string MakeUser([FromBody]UserParameters p)
{
...
}
var client = new HttpClient();
client.DefaultRequestHeaders.Accept.Clear();
var response = await client.PostAsJsonAsync(new Uri("http://localhost:4688/"), p);
// do something with response

Your variable p cannot be passed as query string parameter like how you have it. To populate the url and query strings the way you prefer, you would have to write out the rest of the query string and access the object's properties while building the string up.
string queryString = "api/user?name="+p.Name+"&surname="+p.Surname+"&number="+p.Number;
HttpResponseMessage response = await client.GetAsync(queryString);
The MakeUser() method will need to look similar to something below:
[HttpGet]
public string MakeUser(string name, string surname, int number)
{
}
I am not seeing however where you are calling the MakeUser() method. Perhaps in the query string parameter you need to make it 'api/makeuser?'.

You CAN pass the p parameter like you want to, it's perfectly fine, take a look at the FromUri paragraph here where an object is used as a parameter:
https://learn.microsoft.com/en-us/aspnet/web-api/overview/formats-and-model-binding/parameter-binding-in-aspnet-web-api
The method takes an object as a parameter, not the indivudual members. You call it by specifying the members though.

C# paypal IPN communication

I've set up the IPN to communicate with my website within Paypal, but for some reason paypal does not seem to call it. Below is the method that is listening, but its does not seem to get anything.
Could someone please point me in the write direction?
Thanks
[HttpPost]
public void paypalipn(string receiver_email, string receiver_id, string test_ipn, string txn_id, string payer_id, string payer_status, string payment_date, string payment_status, string payment_type)
{
string subject = "Audit - Paypal IPN ";
string buildemail = "receiver_email: " + receiver_email;
buildemail += "receiver_id: "+receiver_id;
buildemail += "<br>test_ipn: "+test_ipn;
buildemail += "<br>txn_id: " + txn_id;
buildemail += "<br>payer_id: " + payer_id;
buildemail += "<br>payer_status: " + payer_status;
buildemail += "<br>payment_date: " + payment_date;
buildemail += "<br>payment_status: " + payment_status;
buildemail += "<br>payment_type: " + payment_type;
Libraries.Email.Product.SendAudit(subject, buildemail);
}

If you are setting your IPN in your PayPal account, make sure that it is enabled and that the URL is correct. Also, if you are setting it in your account you can check your IPN history to see if the IPN POSTs are being sent out. They will either be marked as sent, retrying, or failed. If they are in a failed or retrying status you can click the message and if your server is sending back any error code it should be listed here. Also, check your error logs on your server to make sure the script is not erroring out.

I did something like this:
public class IPNData
{
public string Response { get; set; }
public NameValueCollection Args { get; set; }
}
Then a method for collecting data from the request, and sends the data to Paypal for verification.
IPNData GetIPNData()
{
var ipnData = new IPNData();
var param = Request.BinaryRead(HttpContext.Request.ContentLength);
var ipnStr = Encoding.ASCII.GetString(param);
ipnData.Args = HttpUtility.ParseQueryString(ipnStr);
// Return the ipn string to paypal for validation
ipnStr += "&cmd=_notify-validate";
var request = (HttpWebRequest)WebRequest.Create("https://www.paypal.com/cgi-bin/webscr");
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = strRequest.Length;
using (var sw = new StreamWriter(request.GetRequestStream(), Encoding.ASCII))
{
sw.Write(ipnStr);
}
using (var sr = new StreamReader(request.GetResponse().GetResponseStream()))
{
// Response should be "VERIFIED"
ipnData.Response = sr.ReadToEnd();
}
return ipnData;
}
PaymentController.cs example for a subscriptionpayment, or if a user cancel a subscription.
public ActionResult PaypalIPNExample()
{
var ipn = GetIPNData();
if (ipn.Response != "VERIFIED")
{
// Do some logging
return null;
}
var type = ipn.Args["txn_type"];
var email = ipn.Args["payer_email"];
var transactionId = ipn.Args["txn_id"];
switch (type)
{
case "subscr_cancel":
UserService.CancelSubscription(email);
break;
case "subscr_payment":
if (ipn.Args["payment_status"].Equals("Completed"))
{
LogPayment(email, transactionId);
UserService.ExtendMembership(email);
}
break;
default:
// Do some logging?
break;
}
return Json("ok");
}

When I was debugging PayPal IPN responses, I did something like this:
string keysReceived = "";
foreach (string key in Request.Params.AllKeys)
keysReceived += "\r\nKey: " + key + ", Val: " + Request.Params[key];
string debugLogPath = HttpContext.Server.MapPath("/") + "debug_PayPalNotify.log";
System.IO.File.AppendAllText(debugLogPath, keysReceived);
Note the use of the global object Request. You can do a lot with that for debugging.