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401 (Unauthorized) error on Azure

See original GitHub issue

I am getting the following error on Azure: Flurl.Http.FlurlHttpException: Request to failed with status code 401 (Unauthorized). at Flurl.Http.Configuration.FlurlMessageHandler.d__1.MoveNext() in C:\projects\flurl\src\Flurl.Http.Shared\Configuration\FlurlMessageHandler.cs:line 59 --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Net.Http.HttpClient.d__58.MoveNext()

It works flawlessly for a day or two with requests made every few hours, then the above exception starts being thrown. It looks like the crumb parameter is empty? What could cause that?

Issue Analytics

  • State:closed
  • Created 6 years ago
  • Comments:5 (2 by maintainers)

github_iconTop GitHub Comments

pljanotcommented, Jul 14, 2017

Hello guys, I will just share some of my slim version of flurlClient with repeat logic for generic FlurlHttpException. Maybe you will find it usefull:

` public class YahooFlurlClient { private static string _crumb;

    private const string QueryUrl = "";
    private const string CrumbUrl = "";

    private const string Period1Tag = "period1";
    private const string Period2Tag = "period2";
    private const string IntervalTag = "interval";
    private const string EventsTag = "events";
    private const string CrumbTag = "crumb";

    private static readonly IDictionary<Period, string> PeriodMap = new Dictionary<Period, string>
        {Period.Daily, "d"},
        {Period.Weekly, "w"},
        {Period.Monthly, "m"}

    public static async Task<Stream> GetResponseStreamAsync(string symbol, DateTime? startTime, DateTime? endTime,
        Period period = Period.Daily, string events= "history")
        var yahooClient = YahooClientFactory.GetYahooClient;

        //Example URI
        var url = QueryUrl
            .SetQueryParam(Period1Tag, (startTime ?? new DateTime(1970, 1, 1)).ToUnixTimestamp())
            .SetQueryParam(Period2Tag, (endTime ?? DateTime.Now).ToUnixTimestamp())
            .SetQueryParam(IntervalTag, $"1{PeriodMap[period]}")
            .SetQueryParam(EventsTag, events)
            .SetQueryParam(CrumbTag, YahooClientFactory.Crumb);

            return await yahooClient.EnableCookies()
        catch (Exception ex) when (!(ex is FlurlHttpException))
            return await yahooClient.EnableCookies()

public static class YahooClientFactory
    public static IFlurlClient GetYahooClient => yahooClientInstance;
    public static string Crumb { get; }

    private static readonly IFlurlClient yahooClientInstance;
    private const string CookieUrl = "";

    private static string userAgent = "User-Agent";
    private static string headerString =
        "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36";
    private const string CrumbUrl = "";

    static YahooClientFactory()
        yahooClientInstance =
            new FlurlClient()
                .WithHeader(userAgent, headerString)


        Crumb = yahooClientInstance

public enum Period

public static class UtilsExtension

    private static readonly DateTime DefaultUnixDateTime = new DateTime(1970, 1, 1);

    public static string Name<T>(this T @enum)
        string name = @enum.ToString();
        if (typeof(T).GetMember(name).First().GetCustomAttribute(typeof(EnumMemberAttribute))
                is EnumMemberAttribute attr && attr.IsValueSetExplicitly)
            name = attr.Value;
        return name;

    public static T GetValue<T>(this string str)
        => (T)Convert.ChangeType(str, typeof(T));

    public static string ToUnixTimestamp(this DateTime dateTime)
        => ((DateTimeOffset)dateTime).ToUnixTimeSeconds().ToString();


} `

mayerwincommented, Jul 14, 2017

Thanks a lot! It seems to work much better already, I’ll let you know if I still encounter issues.

Read more comments on GitHub >

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