Develop Reference

POST Json web API C#

I am trying post api through HTTP client in C#, For authorization ,we send Bearer token.
But it is not getting inserted in the client side. It throws an error.
My code here:
ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;
string result = "";
using (var client = new HttpClient(new HttpClientHandler() { UseDefaultCredentials = true }))
{
client.BaseAddress = new Uri(baseURL);
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Add("Cookie", "ebpPermHash=-396055074);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.Add("Authorization", "Bearer " + authtoken);
client.DefaultRequestHeaders.Add("Accept-Encoding", "gzip, deflate");
client.DefaultRequestHeaders.Add("Accept-Language", "en-GB,en-US;q=0.9,en;q=0.8");
client.DefaultRequestHeaders.Add("Cache-Control", "no-cache")
client.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36");
client.DefaultRequestHeaders.Add("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8");
HttpResponseMessage response = client.PostAsJsonAsync("/v2/bb/sa", payModel).Result;
var responseString = response.Content.ReadAsStringAsync();
result = responseString.Result;
dynamic data = JObject.Parse(result);
string throwresult = Convert.ToString(data);
result = data.authToken;
logErr.ControlLog(throwresult);
}
return result;
But I am getting error like:
exceptionType": "com.ebpsource.exception.AuthenticationFailedException",
"name": "AUTHENTICATION_REQUIRED",
"message": "Authentication is required to call 'Resource.execute'",
"address": "/service/Resource.execute",
"httpRequestBody": {
"header": {
"config": {
"action": "insert",
"resourceName": "sa"
}
Thanks in advance.

I suggest you check your backend with Postman first, to verify if it is a backend issue or a client issue

you have a bug, a wrong syntax to add a token. And plus to many headers. Try this
using (var client = new HttpClient())
{
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
var contentType = new MediaTypeWithQualityHeaderValue("application/json");
client.DefaultRequestHeaders.Accept.Add(contentType);
client.BaseAddress = new Uri(baseAddress);
var jsonData = JsonConvert.SerializeObject(payModel);
var contentData = new StringContent(jsonData, Encoding.UTF8, "application/json");
var response = client.PostAsync("/v2/bb/sa", contentData).Result;
if (response.IsSuccessStatusCode)
{
var stringData = response.Content.ReadAsStringAsync().Result;
var result = JsonConvert.DeserializeObject<object>(stringData);
}
}
UPDATE
if you need to add cookies you can do it this way
var cookieContainer = new CookieContainer();
using (var handler = new HttpClientHandler() { CookieContainer = cookieContainer })
using (var client = new HttpClient(handler))
{
....
cookieContainer.Add(baseAddress, new Cookie("CookieName", "cookie_value"));
.....
}

Unable to fetch data using HttpWebRequest or HtmlAgilityPack

I am trying to make web scraper in C# for NSE. The code works with other sites but when ran on https://www.nseindia.com/ it gives error - An error occurred while sending the request. Unable to read data from the transport connection: Operation timed out.
I have tried with two different approaches Try1() & Try2().
Can anyone please tell what I am missing in my code?
class Program
{
public void Try1() {
HtmlWeb web = new HtmlWeb();
HttpStatusCode statusCode = HttpStatusCode.OK;
web.UserAgent = GetUserAgent();
web.PostResponse = (request, response) =>
{
if (response != null)
{
statusCode = response.StatusCode;
Console.WriteLine("Status Code: " + statusCode);
}
};
Task<HtmlDocument> task = web.LoadFromWebAsync(GetURL());
HtmlDocument document = task.Result;
}
public void Try2() {
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(GetURL());
request.UserAgent = GetUserAgent();
request.Accept= "*/*;";
using (var response = (HttpWebResponse)(request.GetResponse()))
{
HttpStatusCode code = response.StatusCode;
if (code == HttpStatusCode.OK)
{
using (StreamReader streamReader = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
{
HtmlDocument htmlDoc = new HtmlDocument();
htmlDoc.OptionFixNestedTags = true;
htmlDoc.Load(streamReader);
Console.WriteLine("Document Loaded.");
}
}
}
}
private string GetURL() {
// return "https://html-agility-pack.net/";
return "https://www.nseindia.com/";
}
private string GetUserAgent() {
return "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.106 Safari/537.36";
}
}

Your are lack of headers towards Accept and others so it couldn't response back.
Besides that, I would recommend you using HttpClient instead of HttpWebRequest
public static async Task GetHtmlData(string url)
{
HttpClient httpClient = new HttpClient();
using (var request = new HttpRequestMessage(HttpMethod.Get, new Uri(url)))
{
request.Headers.TryAddWithoutValidation("Accept", "text/html,application/xhtml+xml,application/xml, charset=UTF-8, text/javascript, */*; q=0.01");
request.Headers.TryAddWithoutValidation("Accept-Encoding", "gzip, deflate, br");
request.Headers.TryAddWithoutValidation("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.163 Safari/537.36 OPR/67.0.3575.137");
request.Headers.TryAddWithoutValidation("Accept-Charset", "ISO-8859-1");
request.Headers.TryAddWithoutValidation("X-Requested-With", "XMLHttpRequest");
using (var response = await httpClient.SendAsync(request).ConfigureAwait(false))
{
response.EnsureSuccessStatusCode();
using (var responseStream = await response.Content.ReadAsStreamAsync().ConfigureAwait(false))
using (var decompressedStream = new GZipStream(responseStream, CompressionMode.Decompress))
using (var streamReader = new StreamReader(decompressedStream))
{
var result = await streamReader.ReadToEndAsync().ConfigureAwait(false);
HtmlDocument htmlDoc = new HtmlDocument();
htmlDoc.OptionFixNestedTags = true;
htmlDoc.LoadHtml(result);
Console.WriteLine(result);
Console.WriteLine("Document Loaded.");
}
}
}
Use it by
await GetHtmlData("https://www.nseindia.com/");

x-www-form-urlencoded in Xamarin

I'm working on Xamarin.Android App. I have to consume rest API of content type x-www-form-urlencoded. I'm unable to call the Rest API Successfully, before this, I consumed many web services but I'm working on this type of API first time. I'm stuck in this.
I tried two ways to consume it:
public static string makePostEncodedRequest(string url, string jsonparams)
{
string ret = "";
var httpwebrequest = (HttpWebRequest)WebRequest.Create(url);
httpwebrequest.ContentType = "application/x-www-form-urlencoded";
//httpwebrequest.Accept = Config.JsonHeaderAJ;
httpwebrequest.Method = Methods.Post.ToString();
byte[] bytearray = Encoding.UTF8.GetBytes(jsonparams);
using (var streamWriter = new StreamWriter(httpwebrequest.GetRequestStream(), Encoding.ASCII))
{
streamWriter.Write(bytearray);
streamWriter.Flush();
streamWriter.Close();
}
var httpResponse = (HttpWebResponse)httpwebrequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
ret = streamReader.ReadToEnd();
}
return ret;
}
the next one is:
Dictionary<string, string> requestParams = new Dictionary<string, string ();
requestParams.Add("value=", data1);
requestParams.Add("&value=", data2);
using (HttpClient client = new HttpClient())
{
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/x-www-form-urlencoded"));
HttpResponseMessage response = client.PostAsync(Config.DomainURl + Config.StudentLoginUrl, new FormUrlEncodedContent(requestParams)).Result;
var tokne = response.Content.ReadAsStringAsync().Result;
}

i have used the following code for authenticating user in my project might help you.
public static async Task<UserData> GetUserAuth(UserAuth userauth)
{
bool asd= CheckNetWorkStatus().Result;
if (asd)
{
var client = new HttpClient(new NativeMessageHandler());
client.BaseAddress = new Uri(UrlAdd);// ("http://192.168.101.119:8475/");
var postData = new List<KeyValuePair<string, string>>();
var dto = new UserAuth { grant_type = userauth.grant_type, password = userauth.password, username = userauth.username };
var nvc = new List<KeyValuePair<string, string>>();
nvc.Add(new KeyValuePair<string, string>("grant_type", userauth.grant_type));
nvc.Add(new KeyValuePair<string, string>("password", userauth.password));
nvc.Add(new KeyValuePair<string, string>("username", userauth.username));
var req = new HttpRequestMessage(HttpMethod.Post, UrlAdd + "token") { Content = new FormUrlEncodedContent(nvc) };
var res = await client.SendAsync(req);
if (res.IsSuccessStatusCode)
{
string result = await res.Content.ReadAsStringAsync();
var userData = JsonConvert.DeserializeObject<UserData>(result);
userData.ErrorMessage = "true";
return userData;
}
else
{
UserData ud = new UserData();
ud.ErrorMessage = "Incorrect Password";
return ud;
}
}
else
{
UserData ud = new UserData();
ud.ErrorMessage = "Check Ur Connectivity";
return ud;
}
}

httpclient header + content joined PostAsyn

I am trying to make a PostAsync request with c#. The following is my code.
static void Main(string[] args)
{
CookieContainer cookies = new CookieContainer();
HttpClientHandler handler = new HttpClientHandler();
handler.CookieContainer = cookies;
using (var client = new HttpClient(handler))
{
using (HttpResponseMessage getResponse = client.GetAsync("http://google.com").Result)
{
CheckStatusCode(getResponse);
String header = getResponse.Headers.ToString();
var content = CreateCollection(getResponse.Content);
var _stringHeaderContent = header + "\r" + content;
HttpContent _content = new StringContent(_stringHeaderContent, Encoding.UTF8);
Console.WriteLine(_content);
using (HttpResponseMessage postResponse = client.PostAsync("http://google.com",_content).Result)
{
Console.WriteLine(postResponse.Headers);
CheckStatusCode(postResponse);
Console.WriteLine(postResponse.Headers);
}
}
}
}
methods:
public static void CheckStatusCode(HttpResponseMessage response)
{
if (response.StatusCode != HttpStatusCode.OK)
throw new Exception(String.Format(
"Server error (HTTP {0}: {1}).",
response.StatusCode,
response.ReasonPhrase));
else
Console.WriteLine("200");
}
public static String CreateCollection(HttpContent content)
{
var myContent = content.ReadAsStringAsync().Result;
HtmlNode.ElementsFlags.Remove("form");
string html = myContent;
var doc = new HtmlAgilityPack.HtmlDocument();
doc.LoadHtml(html);
var input = doc.DocumentNode.SelectSingleNode("//*[#name='__Token']");
var token = input.Attributes["value"].Value;
//add all necessary component to collection
NameValueCollection collection = new NameValueCollection();
collection.Add("__Token", token);
collection.Add("returnURL", "");
collection.Add("Email", "11111111#hotmail.com");
collection.Add("Password", "1234");
String queryString = GenerateQueryString(collection);
return queryString;
}
public static string GenerateQueryString(NameValueCollection collection)
{
var array = (from key in collection.AllKeys
from value in collection.GetValues(key)
select string.Format("{0}={1}", WebUtility.UrlEncode(key), WebUtility.UrlEncode(value))).ToArray();
return string.Join("&", array);
}
The problem I am having with this code is nothing gets stored in _content. I am trying to make a postAsync request with the header and a part of the content joined. however when I make the postAsync request nothing is stored in _content. Therefore the request fails.
Can anyone explain to me how I can make a postAsync request with _stringHeaderContent?
Regards

This is the way how to use PostAsync:
...
var httpClient = new HttpClient();
var postData = new List<KeyValuePair<string, string>>();
postData.Add(new KeyValuePair<string, string>("a", "1"));
postData.Add(new KeyValuePair<string, string>("b", "2"));
var content = new FormUrlEncodedContent(postData);
var result = httpClient.PostAsync("http://127.0.0.1/a.php", content).Result;
...

Calling a rest api with username and password - how to

I am new to rest api's and calling them via .NET
I have an api: https://sub.domain.com/api/operations?param=value&param2=value
The notes for the api say that to authorize I need to use the basic access authentication - how do I do that?
I currently have this code:
WebRequest req = WebRequest.Create(#"https://sub.domain.com/api/operations?param=value&param2=value");
req.Method = "GET";
//req.Credentials = new NetworkCredential("username", "password");
HttpWebResponse resp = req.GetResponse() as HttpWebResponse;
However I get a 401 unauthorized error.
What am I missing, how do I form api calls using the basic access auth?

If the API says to use HTTP Basic authentication, then you need to add an Authorization header to your request. I'd alter your code to look like this:
WebRequest req = WebRequest.Create(#"https://sub.domain.com/api/operations?param=value&param2=value");
req.Method = "GET";
req.Headers["Authorization"] = "Basic " + Convert.ToBase64String(Encoding.Default.GetBytes("username:password"));
//req.Credentials = new NetworkCredential("username", "password");
HttpWebResponse resp = req.GetResponse() as HttpWebResponse;
Replacing "username" and "password" with the correct values, of course.

You can also use the RestSharp library
for example
var userName = "myuser";
var password = "mypassword";
var host = "170.170.170.170:333";
var client = new RestClient("https://" + host + "/method1");
client.Authenticator = new HttpBasicAuthenticator(userName, password);
var request = new RestRequest(Method.POST);
request.AddHeader("Accept", "application/json");
request.AddHeader("Cache-Control", "no-cache");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json","{}",ParameterType.RequestBody);
IRestResponse response = client.Execute(request);

Here is the solution for Rest API
class Program
{
static void Main(string[] args)
{
BaseClient clientbase = new BaseClient("https://website.com/api/v2/", "username", "password");
BaseResponse response = new BaseResponse();
BaseResponse response = clientbase.GetCallV2Async("Candidate").Result;
}
public async Task<BaseResponse> GetCallAsync(string endpoint)
{
try
{
HttpResponseMessage response = await client.GetAsync(endpoint + "/").ConfigureAwait(false);
if (response.IsSuccessStatusCode)
{
baseresponse.ResponseMessage = await response.Content.ReadAsStringAsync();
baseresponse.StatusCode = (int)response.StatusCode;
}
else
{
baseresponse.ResponseMessage = await response.Content.ReadAsStringAsync();
baseresponse.StatusCode = (int)response.StatusCode;
}
return baseresponse;
}
catch (Exception ex)
{
baseresponse.StatusCode = 0;
baseresponse.ResponseMessage = (ex.Message ?? ex.InnerException.ToString());
}
return baseresponse;
}
}
public class BaseResponse
{
public int StatusCode { get; set; }
public string ResponseMessage { get; set; }
}
public class BaseClient
{
readonly HttpClient client;
readonly BaseResponse baseresponse;
public BaseClient(string baseAddress, string username, string password)
{
HttpClientHandler handler = new HttpClientHandler()
{
Proxy = new WebProxy("http://127.0.0.1:8888"),
UseProxy = false,
};
client = new HttpClient(handler);
client.BaseAddress = new Uri(baseAddress);
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var byteArray = Encoding.ASCII.GetBytes(username + ":" + password);
client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", Convert.ToBase64String(byteArray));
baseresponse = new BaseResponse();
}
}