public static async ValueTask <RemoteJSDataStream> CreateRemoteJSDataStreamAsync(
RemoteJSRuntime runtime,
IJSStreamReference jsStreamReference,
long totalLength,
long signalRMaximumIncomingBytes,
TimeSpan jsInteropDefaultCallTimeout,
CancellationToken cancellationToken = default)
{
// Enforce minimum 1 kb, maximum 50 kb, SignalR message size.
// We budget 512 bytes overhead for the transfer, thus leaving at least 512 bytes for data
// transfer per chunk with a 1 kb message size.
// Additionally, to maintain interactivity, we put an upper limit of 50 kb on the message size.
var chunkSize = signalRMaximumIncomingBytes > 1024 ?
(int)Math.Min(signalRMaximumIncomingBytes, 50 * 1024) - 512 :
throw new ArgumentException($"SignalR MaximumIncomingBytes must be at least 1 kb.");
var streamId = runtime.RemoteJSDataStreamNextInstanceId++;
var remoteJSDataStream = new RemoteJSDataStream(runtime, streamId, totalLength, chunkSize, jsInteropDefaultCallTimeout, cancellationToken);
await runtime.InvokeVoidAsync("Blazor._internal.sendJSDataStream", jsStreamReference, streamId, chunkSize);
return(remoteJSDataStream);
}
// ReceiveJSDataChunk is used in a fire-and-forget context, so it's responsible for its own
// error handling.
internal async Task <bool> ReceiveJSDataChunk(long streamId, long chunkId, byte[] chunk, string error)
{
AssertInitialized();
AssertNotDisposed();
try
{
return(await Renderer.Dispatcher.InvokeAsync(() =>
{
return RemoteJSDataStream.ReceiveData(JSRuntime, streamId, chunkId, chunk, error);
}));
}
catch (Exception ex)
{
// An error completing JS interop means that the user sent invalid data, a well-behaved
// client won't do this.
Log.ReceiveJSDataChunkException(_logger, streamId, ex);
await TryNotifyClientErrorAsync(Client, GetClientErrorMessage(ex, "Invalid chunk supplied to stream."));
UnhandledException?.Invoke(this, new UnhandledExceptionEventArgs(ex, isTerminating: false));
return(false);
}
}
