private static Subscriber DefaultCreateRemoteSubscriber(ExecutionResultLink link)
{
return(async(context, unsubscribe) =>
{
var document = CreateDocument(context);
var variables = context.ExecutionContext.CoercedVariableValues;
var result = await link(document, variables, unsubscribe);
var stream = new EventChannel <ExecutionResult>();
var _ = Task.Run(async() =>
{
while (await result.WaitToReadAsync(unsubscribe))
{
if (result.TryRead(out var executionResult))
{
await stream.WriteAsync(
executionResult);
}
}
await result.Completion;
}, unsubscribe);
return Resolve.Subscribe(stream, unsubscribe);
});
GraphQLDocument CreateDocument(ResolverContext context)
{
return(context.ExecutionContext.Document);
}
}
public async Task Should_stream_a_lot()
{
/* Given */
const int count = 10_000;
var unsubscribe = new CancellationTokenSource(TimeSpan.FromMinutes(3));
var query = @"
subscription MessageAdded {
messageAdded {
content
}
}
";
/* When */
var result = await Executor.SubscribeAsync(new ExecutionOptions
{
Document = Parser.ParseDocument(query),
Schema = _executable
}, unsubscribe.Token).ConfigureAwait(false);
for (var i = 0; i < count; i++)
{
var expected = new Message {
Content = i.ToString()
};
await _messagesChannel.WriteAsync(expected);
}
/* Then */
for (var i = 0; i < count; i++)
{
var actualResult = await result.Source.Reader.ReadAsync(unsubscribe.Token).ConfigureAwait(false);
actualResult.ShouldMatchJson(@"{
""data"":{
""messageAdded"": {
""content"": ""{counter}""
}
}
}".Replace("{counter}", i.ToString()));
}
unsubscribe.Cancel();
}
public async Task <Message> AddMessageAsync(
string fromId,
string content)
{
var from = await GetFromAsync(fromId);
var message = new Message
{
Id = $"{++_lastId}",
Content = content,
Timestamp = DateTimeOffset.UtcNow,
From = from
};
_messages.Enqueue(message);
await _messageStream.WriteAsync(message);
return(message);
}