Null reference error when trying to Decode

[BernieJ]

I am getting a null reference error when trying to decode a jwt token without adding a key paramater. In the example code it is shown. I am Using package JWT v 10.1.1

Code generating the token:

public string CreateJWT(Type claims)
{
  var payload = new Dictionary<string, object>
  {
  ...
  { "exp", DateTimeOffset.UtcNow.Add(TokenExpiry).ToUnixTimeSeconds() }
  };

  IJwtAlgorithm algorithm = new HMACSHA256Algorithm();
  IJsonSerializer serializer = new JsonNetSerializer();
  IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
  IJwtEncoder encoder = new JwtEncoder(algorithm, serializer, urlEncoder);
  string key = string.Empty; // cant encode without a key

  var token = encoder.Encode(payload, key);
  return token;
}

Test code:

 [Test]
 public void TestExpiredToken()
 {
   var expiry = new TimeSpan(0, 0, -10, 0);
   var tokenManager = new TokenManagement(expiry);
   var token = tokenManager.CreateJWT(response);

   Assert.Throws<TokenExpiredException>(() =>
   {
     IJsonSerializer serializer = new JsonNetSerializer();
     IDateTimeProvider provider = new UtcDateTimeProvider();

     IJwtValidator validator = new JwtValidator(serializer, provider);
     IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
     IJwtAlgorithm algorithm = new HMACSHA256Algorithm();
     IJwtDecoder decoder = new JwtDecoder(serializer, validator, urlEncoder, algorithm);

    // NullReference error gets thrown
     var decodedClaims = decoder.DecodeToObject<IDictionary<string, object>>(token);
   });
 }

[abatishchev]

Thanks for reporting the issue!
Can you please post the resulting exception stack trace too?

[BernieJ]

Stack trace

System.NullReferenceException: Object reference not set to an instance of an object.
   at JWT.JwtDecoder.<>c.<AllKeysHaveValues>b__20_0(Byte[] key)
   at System.Array.TrueForAll[T](T[] array, Predicate`1 match)
   at JWT.JwtDecoder.AllKeysHaveValues(Byte[][] keys)
   at JWT.JwtDecoder.ValidSymmetricAlgorithm(Byte[][] keys, String decodedPayload, IJwtAlgorithm algorithm, Byte[] bytesToSign, Byte[] decodedSignature)
   at JWT.JwtDecoder.Validate(JwtParts jwt, Byte[][] keys)
   at JWT.JwtDecoder.Decode(JwtParts jwt, Byte[][] keys, Boolean verify)
   at JWT.JwtDecoder.Decode(JwtParts jwt, Byte[] key, Boolean verify)
   at JWT.JwtDecoder.Decode(JwtParts jwt, Boolean verify)
   at JWT.JwtDecoder.DecodeToObject(Type type, JwtParts jwt, Boolean verify)
   at JWT.JwtDecoderExtensions.DecodeToObject[T](IJwtDecoder decoder, JwtParts jwt, Boolean verify)
   at JWT.JwtDecoderExtensions.DecodeToObject[T](IJwtDecoder decoder, String token)
   at POC.Tests.Tests.<>c__DisplayClass2_0.<TestExpiredToken>b__0() in C:\Projects\.net 8 Rest POC\Tests\TokenManagementTests.cs:line 98
   at NUnit.Framework.Assert.Throws(IResolveConstraint expression, TestDelegate code, String message, Object[] args)>