public async Task <Response> GetPage(ReadStreamOptions options, CancellationToken cancellationToken)
{
var operation = options.GetReadOperation();
var page = await operation.Invoke(_streamStore, cancellationToken);
var payloads = await Task.WhenAll(page.Messages
.Select(message => options.EmbedPayload
? message.GetJsonData(cancellationToken)
: Task.FromResult <string>(null))
.ToArray());
return(new Response(
new HALResponse(new object())
.AddLinks(StreamLinks.Self(options))
.AddLinks(StreamLinks.Navigation(page, options.Self))
.AddLinks(StreamLinks.Feed(page))
.AddEmbeddedCollection(
Relations.Message,
page.Messages.Zip(payloads,
(message, payload) => new HALResponse(new
{
message.MessageId,
message.CreatedUtc,
message.Position,
message.StreamId,
message.StreamVersion,
message.Type,
payload
}).AddLinks(StreamMessageLinks.Self(message))))));
}
private static MidFunc GetStream(StreamResource stream) => next => async env =>
{
var context = new OwinContext(env);
var options = new ReadStreamOptions(context.Request);
var response = await stream.GetPage(options, context.Request.CallCancelled);
await context.WriteHalResponse(response);
};
public static Link Self(ReadStreamOptions options) => new Link(
Relations.Self,
options.Self);
