Implement new error code and more error fields.

See discord/discord-api-docs#5574.

Backend/Remora.Discord.API.Abstractions/API/Objects/Errors/IRestError.cs

@@ -31,13 +31,16 @@ namespace Remora.Discord.API.Abstractions.Objects;
 /// <summary>
 /// Represents an error reported by the REST API.
 /// </summary>
+/// <remarks>
+/// This is a combination of the "normal" REST error and the rate limiting error.
+/// </remarks>
 [PublicAPI]
 public interface IRestError
 {
     /// <summary>
     /// Gets the error code.
     /// </summary>
-    DiscordError Code { get; }
+    Optional<DiscordError> Code { get; }
 
     /// <summary>
     /// Gets the per-property error details.
@@ -48,4 +51,14 @@ public interface IRestError
     /// Gets a descriptive error message.
     /// </summary>
     string Message { get; }
+
+    /// <summary>
+    /// Gets a value indicating whether you are globally rate limited.
+    /// </summary>
+    Optional<bool> IsGlobal { get; }
+
+    /// <summary>
+    /// Gets the time (in seconds) after which the request should be retried.
+    /// </summary>
+    Optional<float> RetryAfter { get; }
 }

Backend/Remora.Discord.API.Abstractions/Results/DiscordError.cs

@@ -531,6 +531,11 @@ public enum DiscordError
     /// </summary>
     TagNamesMustBeUnique = 40061,
 
+    /// <summary>
+    /// A service resource is being rate limited.
+    /// </summary>
+    ServiceResourceIsBeingRateLimited = 40062,
+
     /// <summary>
     /// There are no tags available that can be set by non-moderators.
     /// </summary>

Backend/Remora.Discord.API/API/Objects/Errors/RestError.cs

@@ -35,7 +35,9 @@ namespace Remora.Discord.API.Objects;
 [PublicAPI]
 public record RestError
 (
-    DiscordError Code,
+    Optional<DiscordError> Code,
     Optional<IReadOnlyDictionary<string, OneOf<IPropertyErrorDetails, IReadOnlyList<IErrorDetails>>>> Errors,
-    string Message
+    string Message,
+    Optional<bool> IsGlobal,
+    Optional<float> RetryAfter
 ) : IRestError;

Backend/Remora.Discord.API/Extensions/ServiceCollectionExtensions.cs

@@ -939,7 +939,8 @@ private static JsonSerializerOptions AddWebhookObjectConverters(this JsonSeriali
     /// <returns>The options, with the converters added.</returns>
     private static JsonSerializerOptions AddErrorObjectConverters(this JsonSerializerOptions options)
     {
-        options.AddDataObjectConverter<IRestError, RestError>();
+        options.AddDataObjectConverter<IRestError, RestError>()
+            .WithPropertyName(e => e.IsGlobal, "global");
         options.AddDataObjectConverter<IErrorDetails, ErrorDetails>();
 
         return options;

Backend/Remora.Discord.Rest/Polly/DiscordRateLimitPolicy.cs

@@ -138,10 +138,12 @@ bool continueOnCapturedContext
             bucketIdentifier = endpoint;
         }
 
-        var getValue = await cache.RetrieveAsync<RateLimitBucket>(
+        var getValue = await cache.RetrieveAsync<RateLimitBucket>
+        (
             CacheKey.LocalizedStringKey(nameof(Polly), bucketIdentifier),
             cancellationToken
         );
+
         if (getValue.IsDefined(out var rateLimitBucket))
         {
             // We don't reset route-specific rate limits ourselves; that's the responsibility of the returned headers

Tests/Remora.Discord.Tests/Samples/Objects/REST_ERROR/REST_ERROR.json

@@ -30,5 +30,7 @@
             ]
         }
     },
-    "message": "Invalid Form Body"
+    "message": "Invalid Form Body",
+    "global": true,
+    "retry_after": 1
 }

Tests/Remora.Discord.Tests/Samples/Objects/REST_ERROR/REST_ERROR.optionals.json

@@ -0,0 +1,3 @@
+{
+    "message": "Invalid Form Body"
+}