Develop Reference

C# Using CloudProxySharp gone wrong

I want to download the code of a web page but it sends me to a captcha when I am in the presence of a proxy, without it it works fine. I tested with HttpClientHandler and I assigned a proxy. So I searched on the net how to achieve this? I found the CloudProxySharp, which can manage to fill the captcha while being connected to a proxy but either I misunderstood its use or it does not work. By the way, it is my IP that is used during the request and not the one of the proxy. I checked using a simple IP API. I would like to know, you who surely have more experience, why it is my IP that is used and not that of the proxy?
If you need more infos, tell me please.
private async void button2_Click(object sender, EventArgs e)
{
var handler2 = new ClearanceHandler("http://139.99.74.79:8080")
{
UserAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:88.0) Gecko/20100101 Firefox/88.0",
MaxTimeout = 60000,
};
var client = new HttpClient(handler2);
HttpResponseMessage response = await client.GetAsync("https://v4.ident.me/");
var s = await response.Content.ReadAsStringAsync();
MessageBox.Show(s);
}

How to get json from Secured API

I did an api, for the exemple i will call it: https://testapp.azurewebsites.net.
I did the Authentication / Authorization in Azure for google Facebook and Miscrosoft account.
Then i want to consume it in xamarin for my Android/iOS app, so i did the login button etc but when I'm authentify i can't get the json of my api URL: "https://testapp.azurewebsites.net/api/Test/allCoordinates".
It work's perfectly in my browser and in postman... This is my code in C#:
var requestCoord = new OAuth2Request("GET", new Uri(URL),null , e.Account);
var responseCoord = await requestCoord.GetResponseAsync(); //it works for google userinfo but not for my Api...
string coordJson = await responseCoord.GetResponseTextAsync();
var mapTest = JsonConvert.DeserializeObject<List<CustomPin>>(coordJson);
In Postman it works and i can see this code for C# from postman:
var client = new RestClient("https://testapp.azurewebsites.net/api/Test/allCoordinates?access_token=ya29.a0AfH6SMCEGy4tP_zngNEhAcpf31d3O_ZYl7NE9QJjbKrW0KPh-dC7PjNmz-KOCbkySRtuwDJdg2ckhiTaTdIEsONxVhFhK3NpnUk9iITyCB1BnwpWJwNEEivxg0pL93UPP9r4UYf1dHEiTVd63eydfV7HoKlxExMFtS8");
client.Timeout = -1;
var request = new RestRequest(Method.GET);
request.AddHeader("User-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36");
request.AddHeader("Cookie", "ARRAffinity=d2e047f134af60dd8e0802593ad5206002e99e56a6231fee0e85747cfa96ea6f; AppServiceAuthSession=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");
IRestResponse response = client.Execute(request);
Console.WriteLine(response.Content);
But how to find the cookie data in Xamarin ? and call this url ?
If you have any idea to make this Http Get from protected webapi i will help me so much !!!
Thanks a lot
If you need more precision let me know;)

HttpClient returns html from API

Trying to use the HttpClient to get a json response from an API but keep getting html response. In the browser and in Postman I get the result in json just by typing in the url. When using RestSharp I also get the response in json. What do I need to add to get the response in json? The variable responseString in a html string, not a json string.
I use .net core 3.1.
Here's the code:
class Program
{
static async Task Main(string[] args)
{
var response = await GetResponse();
System.Console.ReadKey();
}
public static async Task<string> GetResponse()
{
var client = new HttpClient();
client.BaseAddress = new Uri("https://musicbrainz.org/ws/2/");
client.DefaultRequestHeaders.Add("Accept",
"application/json");
using var response = await client.GetAsync((
"/artist/5b11f4ce-a62d-471e-81fc-a69a8278c7da?fmt=json&inc=url-rels+release-groups"));
response.EnsureSuccessStatusCode();
var responseString = await response.Content.ReadAsStringAsync();
return responseString;
}
}

I think the API is looking for a User-Agent.
Try to Add
client.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36")

As a side note, you might want to consider declaring your HttpClient as static. It is recommended in its documentation. Also if you want json, you need to use DeserializeObject method:
var result = JsonConvert.DeserializeObject<RootObject>(responseString);
You just need to make sure that you have already installed the Newtonsoft.Json from Nuget packages and also added the following to your using directives:
using Newtonsoft.Json;

JSON Deserialization in C# error

I'm trying to deserialize some JSON in C#, but when I run my program I'm getting this error message:
I've looked through all my code, and I can't find a "<" anywhere there shouldn't be one, and I went to the web address that the json is coming from:
http://forecast.weather.gov/MapClick.php?lat=47.1211&lon=-88.5694&FcstType=json,
and there isn't a "<" character. I used json2csharp.com to translate to C# classes, and everything there seems fine as well. Any thoughts? Here is the part of my code where I try to do all of this:
var http = new HttpClient();
var url = "http://forecast.weather.gov/MapClick.php?lat=47.1211&lon=-88.5694&FcstType=json";
var response = await http.GetAsync(url);
var result = await response.Content.ReadAsStringAsync();
var serializer = new DataContractJsonSerializer(typeof(RootObject2));
var ms = new MemoryStream(Encoding.UTF8.GetBytes(result));
var data = (RootObject2)serializer.ReadObject(ms);
return data;

Your call is failing because you are not setting a header the API is expecting. Add a user agent and check for success prior to attempting to read the response.
var http = new HttpClient();
var url = "http://forecast.weather.gov/MapClick.php?lat=47.1211&lon=-88.5694&FcstType=json";
//Supply the same header as chrome
http.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.84 Safari/537.36");
var response = await http.GetAsync(url);
if (response.IsSuccessStatusCode)
{
var result = await response.Content.ReadAsStringAsync();
var ms = new MemoryStream(Encoding.UTF8.GetBytes(result));
var serializer = new DataContractJsonSerializer(typeof(RootObject2));
var data = (RootObject2)serializer.ReadObject(ms);
}

check that answer, it says some issue with the connection, that he was not receiving the full response from the API
Unexpected character encountered while parsing value:

C# HttpClient.SendAsync always returns 404 but URL works in browser

I am developing an C# console application for testing whether a URL is valid or not. It works well for most of URLs. But we found that there are some cases the application always got 404 response from target site but the URLs actually work in the browser. And those URLs also works when I tried them in the tools such as DHC (Dev HTTP Client).
In the beginning, I though that this could be the reason of not adding right headers. But after tried using Fiddler to compose a http request with same headers, it works in Fiddler.
So what's wrong with my code? Is there any bug in .NET HttpClient?
Here are the simplified code of my test application:
class Program
{
static void Main(string[] args)
{
var urlTester = new UrlTester("http://www.hffa.it/short-master-programs/fashion-photography");
Console.WriteLine("Test is started");
Task.WhenAll(urlTester.RunTestAsync());
Console.WriteLine("Test is stoped");
Console.ReadKey();
}
public class UrlTester
{
private HttpClient _httpClient;
private string _url;
public UrlTester(string url)
{
_httpClient = new HttpClient
{
Timeout = TimeSpan.FromMinutes(1)
};
// Add headers
_httpClient.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.80 Safari/537.36");
_httpClient.DefaultRequestHeaders.Add("Accept-Encoding", "gzip,deflate,sdch");
_httpClient.DefaultRequestHeaders.Add("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8");
_httpClient.DefaultRequestHeaders.Add("Accept-Language", "sv-SE,sv;q=0.8,en-US;q=0.6,en;q=0.4");
_url = url;
}
public async Task RunTestAsync()
{
var httpRequestMsg = new HttpRequestMessage(HttpMethod.Get, _url);
try
{
using (var response = await _httpClient.SendAsync(httpRequestMsg, HttpCompletionOption.ResponseHeadersRead))
{
Console.WriteLine("Response: {0}", response.StatusCode);
}
}
catch (HttpRequestException e)
{
Console.WriteLine(e.InnerException.Message);
}
}
}
}

This appears to be an issue with the accepted languages. I got a 200 response when using the following Accept-Language header value
_httpClient.DefaultRequestHeaders.Add("Accept-Language", "en-GB,en-US;q=0.8,en;q=0.6,ru;q=0.4");
p.s. I assume you know in your example _client should read _httpClient in the urlTester constructor or it wont build.

Another possible cause of this problem is if the url you are sending is over approx 2048 bytes long. At that point the content (almost certainly the query string) can become truncated and this in turn means that it may not be matched correctly with a server side route.
Although these urls were processed correctly in the browser, they also failed using the get command in power shell.
This issue was resolved by using a POST with key value pairs instead of using a GET with a long query string.