Server errors get reported as BadRequest

[ivankom82]

When a server response does not contain json, it is failed to parse inside Forge.AI and gets translated into BadRequest which it isn't.
Is it possible to retain the original response code at least? See the attached snippet for 504 on gateway timeout.

2025/06/10 13:15:06.351|0059|Info| [System.Net.Http.HttpClient.Forge.OpenAI.ClientHandler] Received HTTP response headers after 900479.5136ms - 504 2025/06/10 13:15:06.351|0059|Info| [System.Net.Http.HttpClient.Forge.OpenAI.LogicalHandler] End processing HTTP request after 900479.5991ms - 504 2025/06/10 13:15:06.352|0059|Debg| [Forge.OpenAI.Infrastructure.ApiHttpService] ApiCall, response arrived from baseAddress: https://api.openai.com/, uri: https://api.openai.com/v1/audio/transcriptions, method: POST 2025/06/10 13:15:06.352|0059|Debg| [Forge.OpenAI.Infrastructure.ApiHttpService] ApiCall, response indicates an unsuccessful operation from https://api.openai.com/https://api.openai.com/v1/audio/transcriptions, method: POST 2025/06/10 13:15:06.369|0059|Erro| [Forge.OpenAI.Infrastructure.ApiHttpService] 'e' is an invalid start of a value. Path: $ | LineNumber: 0 | BytePositionInLine: 0. System.Text.Json.JsonException: 'e' is an invalid start of a value. Path: $ | LineNumber: 0 | BytePositionInLine: 0. ---> System.Text.Json.JsonReaderException: 'e' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0. at System.Text.Json.ThrowHelper.ThrowJsonReaderException(Utf8JsonReader& json, ExceptionResource resource, Byte nextByte, ReadOnlySpan1 bytes)
at System.Text.Json.Utf8JsonReader.ConsumeValue(Byte marker)
at System.Text.Json.Utf8JsonReader.ReadFirstToken(Byte first)
at System.Text.Json.Utf8JsonReader.ReadSingleSegment()
at System.Text.Json.Serialization.JsonConverter1.ReadCore(Utf8JsonReader& reader, T& value, JsonSerializerOptions options, ReadStack& state) --- End of inner exception stack trace --- at System.Text.Json.ThrowHelper.ReThrowWithPath(ReadStack& state, JsonReaderException ex) at System.Text.Json.Serialization.JsonConverter1.ReadCore(Utf8JsonReader& reader, T& value, JsonSerializerOptions options, ReadStack& state)
at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan1 json, JsonTypeInfo1 jsonTypeInfo)
at Forge.OpenAI.Models.Common.HttpOperationResult..ctor(Exception exception, HttpStatusCode httpStatusCode, String errorMessage)
at Forge.OpenAI.Infrastructure.ApiHttpService.<>c__DisplayClass27_02.<<ApiCall>b__0>d.MoveNext() --- End of stack trace from previous location --- at Forge.OpenAI.Infrastructure.ApiHttpService.ErrorHandlerContextAsync[TResult](Func2 func, CancellationToken cancellationToken)`

[JZO001]

@ivankom82 help me a bit please, send me an example (prompt, data, etc), which helps me to reproduce this scenario. Thanks.

[ivankom82]

It's a simple transcription request using Forge.OpenAI.Interfaces.Services.ITranscriptionService which very infrequently fails with this error code. The TranscriptionRequest itself and the recording are both valid.
You don't need to reproduce this, it's clear what happens from the given above stack trace.

ApiHttpService.cs: 232
result = new HttpOperationResult<Stream>(new Exception(response.StatusCode.ToString(), new Exception(errorResponse)), response.StatusCode, errorResponse);

The problem is that HttpOperationResult(HttpOperationResult(Exception exception, HttpStatusCode httpStatusCode, string errorMessage = null) expects json for the last parameter and throws an exception when it's not (HttpOperationResult.cs, lines 39-47):

if (!string.IsNullOrWhiteSpace(errorMessage))
{
    var serializeOptions = new JsonSerializerOptions
    {
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase
    };

    ErrorResponse = JsonSerializer.Deserialize<ErrorResponse>(errorMessage, serializeOptions);
}

So it seems you just need to expect this case and skip populating ErrorResponse when this happens (i.e. just catch the exception here).