feature: Handle error 429 when connecting websocket (#213)

* feature: Handle error 429 when connecting websocket

* Add preprocessor directive for NET6_0_OR_GREATER when checking for connection rate limit

CryptoExchange.Net/RateLimiting/Guards/RetryAfterGuard.cs

@@ -21,25 +21,35 @@ namespace CryptoExchange.Net.RateLimiting.Guards
         public string Name => "RetryAfterGuard";
 
         /// <inheritdoc />
-        public string Description => $"Pause requests until after {After}";
+        public string Description => $"Pause {Type} until after {After}";
 
         /// <summary>
         /// The timestamp after which requests are allowed again
         /// </summary>
         public DateTime After { get; private set; }
 
+        /// <summary>
+        /// The type of rate limit item this guard is for
+        /// </summary>
+        public RateLimitItemType Type { get; private set; }
+
         /// <summary>
         /// ctor
         /// </summary>
         /// <param name="after"></param>
-        public RetryAfterGuard(DateTime after)
+        /// <param name="type"></param>
+        public RetryAfterGuard(DateTime after, RateLimitItemType type)
         {
             After = after;
+            Type = type;
         }
 
         /// <inheritdoc />
         public LimitCheck Check(RateLimitItemType type, RequestDefinition definition, string host, string? apiKey, int requestWeight)
         {
+            if (type != Type)
+                return LimitCheck.NotApplicable;
+
             var dif = (After + _windowBuffer) - DateTime.UtcNow;
             if (dif <= TimeSpan.Zero)
                 return LimitCheck.NotApplicable;

CryptoExchange.Net/RateLimiting/Interfaces/IRateLimitGate.cs

@@ -29,8 +29,9 @@ namespace CryptoExchange.Net.RateLimiting.Interfaces
         /// Set a RetryAfter guard, can be used when a server rate limit is hit and a RetryAfter header is specified
         /// </summary>
         /// <param name="retryAfter">The time after which requests can be send again</param>
+        /// <param name="type">RateLimitType</param>
         /// <returns></returns>
-        Task SetRetryAfterGuardAsync(DateTime retryAfter);
+        Task SetRetryAfterGuardAsync(DateTime retryAfter, RateLimitItemType type = RateLimitItemType.Request);
 
         /// <summary>
         /// Returns the 'retry after' timestamp if set

CryptoExchange.Net/RateLimiting/RateLimitGate.cs

@@ -152,7 +152,7 @@ namespace CryptoExchange.Net.RateLimiting
         }
 
         /// <inheritdoc />
-        public async Task SetRetryAfterGuardAsync(DateTime retryAfter)
+        public async Task SetRetryAfterGuardAsync(DateTime retryAfter, RateLimitItemType type)
         {
             await _semaphore.WaitAsync().ConfigureAwait(false);
 
@@ -160,7 +160,7 @@ namespace CryptoExchange.Net.RateLimiting
             {
                 var retryAfterGuard = _guards.OfType<RetryAfterGuard>().SingleOrDefault();
                 if (retryAfterGuard == null)
-                    _guards.Add(new RetryAfterGuard(retryAfter));
+                    _guards.Add(new RetryAfterGuard(retryAfter, type));
                 else
                     retryAfterGuard.UpdateAfter(retryAfter);
             }