internal void RegisterGlue(Glue42 glue)
{
_glue = glue;
UpdateUI(true);
_glue.Interop.ConnectionStatusChanged += InteropConnectionStatusChanged;
// register a streaming endpoint (Glue stream) called GlueDemoTickStream
stream_ = _glue.Interop.RegisterStreamingEndpoint(smb => smb.SetMethodName("GlueDemoTickStream")
.SetParameterSignature("bool reject, string symbol"),
new ServerEventStreamHandler(false)
{
// in each of the stream handler events we have the optional cookie parameter
// that is optionally supplied while registering the stream
// this lambda is invoked when a new subscription request is received
SubscriptionRequestHandler = SubscriptionRequestHandler,
// this lambda is invoked when new subscriber has been connected to a branch
SubscriberHandler = SubscriberHandler,
//this lambda is invoked when a subscriber cancels its subscription or has been kicked (banned) by the publisher
UnsubscribeHandler = UnsubscribeHandler
});
}
public IEventStreamBranch HandleSubscriptionRequest(
IServerEventStream serverEventStream,
IEventStreamSubscriptionRequest subscriptionRequest,
object streamCookie = null)
{
string message = null;
try
{
if (!acceptor_(subscriptionRequest, ref message))
{
subscriptionRequest.Reject(
reply => reply.SetIsFailed(true).SetMessage(message).Build());
return(null);
}
return(subscriptionRequest.Accept(
reply => reply.SetMessage(message ?? "Subscribed").Build()));
}
catch (Exception e)
{
subscriptionRequest.Reject(
reply => reply.SetIsFailed(true)
.SetMessage(string.Format("Unexpected error: {0}", e.Message))
.Build());
return(null);
}
}
private IEventStreamBranch SubscriptionRequestHandler(IServerEventStream stream, IEventStreamSubscriptionRequest request, object cookie)
{
// validate the request
// for demo purposes we have a reject argument sent by the subscriber
bool shouldReject = request.SubscriptionContext.Arguments.GetValueByName("reject", v => v.AsBool);
string symbol = request.SubscriptionContext.Arguments.GetValueByName("symbol", v => v.AsString());
LogMessage($"Subscription request from {request.Caller} for symbol {symbol} - {request.SubscriptionContext.Arguments.AsString()}");
if (shouldReject || string.IsNullOrEmpty(symbol))
{
string rejectionReason = shouldReject ? "rejected as requested" : "rejected because symbol is empty";
string rejectionMsg = $"Subscription request from {request.Caller} {rejectionReason}";
LogMessage(rejectionMsg);
// if we cannot validate the subscription request we can reject it
request.Reject(smrb =>
smrb.SetMessage(rejectionMsg)
.SetContext(cb =>
cb.AddValue("RejectionArgument", new[] { 5, 3, 2, 1, 2 })
.AddValue("MoreRejectionArguments", "sdfgsdfg")).Build());
return(null);
}
// when we validate the subscription request, we can assign the subscriber to a branch
// in this demo we will use the tickMode as a branch (https://docs.glue42.com/glue42-concepts/data-sharing-between-apps/interop/net/index.html#streaming)
// branches are an optional grouping of multiple subscribers to ease data category segregation - the branches are keyed by
// 'any' object supplied by the publisher
// if we don't need a branching mechanism, we then use the 'main' branch by *not* supplying value for branch key.
return(request.Accept(smrb => smrb.Build(), branchKey: symbol));
}
public void HandleSubscriber(
IServerEventStream serverEventStream,
IEventStreamSubscriber subscriber,
IEventStreamBranch branch,
object streamCookie = null)
{
if (subscriberAdded_ != null)
{
subscriberAdded_(subscriber);
}
}
public void HandleSubscriberRemoved(
IServerEventStream serverEventStream,
IEventStreamSubscriber subscriber,
EventStreamSubscriberRemovedContext subscriberRemovedContext,
IEventStreamBranch branch = null,
object streamCookie = null)
{
if (subscriberRemoved_ != null)
{
subscriberRemoved_(subscriber);
}
}
private void UnsubscribeHandler(
IServerEventStream stream,
IEventStreamSubscriber subscriber,
EventStreamSubscriberRemovedContext context,
IEventStreamBranch branch,
object cookie)
{
IEventStreamSubscriptionRequest request = subscriber.Subscription;
// log the subscription cancellation
LogMessage($"Removed subscriber {request.Caller} {request.SubscriptionContext.Arguments.AsString()}");
// remove subscriptions when cancelled
var subscriptionItem = $"{request.Caller.ApplicationName} {request.SubscriptionContext.Arguments.AsString()}";
DispatchAction(() => ListViewSubscriptions.Items.Remove(subscriptionItem));
}
private void SubscriberHandler(IServerEventStream stream, IEventStreamSubscriber subscriber, IEventStreamBranch branch, object cookie)
{
IEventStreamSubscriptionRequest request = subscriber.Subscription;
// log the subscriber
LogMessage($"New subscriber {request.Caller} {request.SubscriptionContext.Arguments.AsString()}");
// push an 'image' to that subscriber which is received *only* by it (last image pattern)
// this will be received as an OOB data - see the demo subscriber code
subscriber.Push(cb =>
cb.AddValue("SubscribersAsImage", _glue.AGMObjectSerializer.Serialize(stream.GetBranches()
.SelectMany(b =>
b.GetSubscribers().Select(sb => sb.Subscription.Caller)))));
// e.g. keep the subscriptions in a list
var subscriptionItem = $"{request.Caller.ApplicationName} {request.SubscriptionContext.Arguments.AsString()}";
DispatchAction(() =>
{
ListViewSubscriptions.Items.Add(subscriptionItem);
ListViewSubscriptions.ScrollIntoView(subscriptionItem);
});
}
public MainWindow()
{
InitializeComponent();
// create a timer for each of the StoreDepartments (branches)
// each timer will push to the relevant branch
timer_.Add(StoreDepartment.Books, new Timer(OnTimerTick, StoreDepartment.Books, 0, 1000));
timer_.Add(StoreDepartment.Apparel, new Timer(OnTimerTick, StoreDepartment.Apparel, 0, 2500));
timer_.Add(StoreDepartment.Food, new Timer(OnTimerTick, StoreDepartment.Food, 0, 5000));
// initialize Glue
glue_ = new Glue42();
// give the publisher an application name
// explicitly turn off Glue Window management, Glue contexts, Glue AppManager, Glue metrics and Glue notifications
// as they're not used in this example
glue_.Initialize("GlueStreamsPublisher", useAppManager: false, useStickyWindows: false,
useContexts: false, useMetrics: false, useNotifications: false);
// detect connection status change and log it to the UI
glue_.Interop.ConnectionStatusChanged += (sender, args) => LogMessage($"Glue is now {args.Status}");
// register a streaming endpoint (Glue stream) called GlueDemoStoreStream
stream_ = glue_.Interop.RegisterStreamingEndpoint(smb => smb.SetMethodName("GlueDemoStoreStream")
.SetParameterSignature("bool reject, int storeDepartment"),
new ServerEventStreamHandler(false)
{
// in each of the stream handler events we have the optional cookie parameter
// that is optionally supplied while registering the stream
// this lambda is invoked when a new subscription request is received
SubscriptionRequestHandler = (stream, request, cookie) =>
{
// validate the request
// for demo purposes we have a reject argument sent by the subscriber
bool reject = request.SubscriptionContext.Arguments.GetValueByName("reject", v => v.AsBool);
StoreDepartment department = request.SubscriptionContext.Arguments.GetValueByName("StoreDepartment",
v => Enum.TryParse(v, true, out StoreDepartment sd) ? sd : StoreDepartment.None);
LogMessage($@"Subscription request from {request.Caller} for StoreDepartment {department}: {request.SubscriptionContext.Arguments.AsString()}");
if (reject || department == StoreDepartment.None)
{
var rejectionMsg = new StringBuilder($"Subscription request from {request.Caller} rejected. Reason(s): ");
if (reject)
{
rejectionMsg.Append("Reject requested;");
}
if (department == StoreDepartment.None)
{
rejectionMsg.Append("StoreDepartment invalid");
}
LogMessage(rejectionMsg.ToString());
// if we cannot validate the subscription request we can reject it
request.Reject(smrb =>
smrb.SetMessage(rejectionMsg.ToString())
.SetContext(cb =>
cb.AddValue("RejectionArgument", new[] { 5, 3, 2, 1, 2 })
.AddValue("MoreRejectionArguments", "sdfgsdfg")).Build());
return(null);
}
// when we validate the subscription request, we can assign the subscriber to a branch
// in this demo we will use the StoreDepartment as a branch (https://docs.glue42.com/g4e/net-interop/index.html#interop-streaming)
// branches are an optional grouping of multiple subscribers to ease data category segregation - the branches are keyed by
// 'any' object supplied by the publisher
// if we don't need a branching mechanism, we then use the 'main' branch by *not* supplying value for branch key.
return(request.Accept(smrb => smrb.Build(), branchKey: department));
},
// this lambda is invoked when new subscriber has been connected to a branch
SubscriberHandler = (stream, subscriber, branch, cookie) =>
{
IEventStreamSubscriptionRequest request = subscriber.Subscription;
// log the subscriber
LogMessage(
$"New subscriber {request.Caller} {request.SubscriptionContext.Arguments.AsString()}");
// push an 'image' to that subscriber which is received *only* by it (last image pattern)
// this will be received as an OOB data - see the demo subscriber code
subscriber.Push(cb =>
cb.AddValue("SubscribersAsImage", glue_.AGMObjectSerializer.Serialize(stream.GetBranches()
.SelectMany(b =>
b.GetSubscribers().Select(sb => sb.Subscription.Caller)))));
// e.g. keep the subscriptions in a list
DispatchAction(() => Subscriptions.Items.Add(request.Caller.ApplicationName +
" " +
request.SubscriptionContext
.Arguments
.AsString()));
},
//this lambda is invoked when a subscriber cancels its subscription or has been kicked (banned) by the publisher
UnsubscribeHandler = (stream, subscriber, unsubscribeCxt, branch, cookie) =>
{
IEventStreamSubscriptionRequest request = subscriber.Subscription;
// log the subscription cancellation
LogMessage(
$"Removed subscriber {request.Caller} {request.SubscriptionContext.Arguments.AsString()}");
// remove subscriptions when cancelled
DispatchAction(() =>
Subscriptions.Items.Remove(request.Caller.ApplicationName + " " +
request.SubscriptionContext.Arguments.AsString()));
}
});
public void HandleStreamClosed(
IServerEventStream serverEventStream,
object streamCookie = null)
{
}
public void HandleStreamBranchClosed(
IServerEventStream serverEventStream,
IEventStreamBranch branch,
object streamCookie = null)
{
}