Modules/GUIs.ClientSuite/Workers/HeartbeatWorker.vb
2019-06-03 14:18:43 +02:00

64 lines
2.1 KiB
VB.net

Imports System.Timers
Imports DigitalData.GUIs.ClientSuite
Imports DigitalData.GUIs.ClientSuite.Base
Imports DigitalData.Modules.EDMIAPI.IDBServiceReference
Imports DigitalData.Modules.Logging
Namespace Workers
Public Class HeartbeatWorker
Inherits BaseClass
Implements IWorker
Private _Channel As IIDBServiceChannel
Public Event OnlineChanged As OnlineChangedEventHandler
Public Delegate Sub OnlineChangedEventHandler(sender As Object, Online As Boolean)
Public ReadOnly Property Interval As Integer = 4000 Implements IWorker.Interval
Public Sub New(LogConfig As LogConfig)
MyBase.New(LogConfig)
End Sub
Public Sub Setup() Implements IWorker.Setup
_Channel = My.ChannelFactory.CreateChannel()
_Channel.Open()
End Sub
Public Async Sub Callback(manager As WorkerManager, e As ElapsedEventArgs) Implements IWorker.Callback
Try
Logger.Debug("Checking if Service is up...")
If _Channel.State = ServiceModel.CommunicationState.Faulted Then
_Channel = My.ChannelFactory.CreateChannel()
End If
' Connect to service and send hearbeat request
Dim oResult = Await _Channel.HeartbeatAsync()
Logger.Debug("Service is online")
SetOnlineState(True)
Catch ex As Exception
Logger.Debug("Service is offline!")
Logger.Error(ex)
SetOnlineState(False)
Finally
My.Application.Service.LastChecked = DateTime.Now
End Try
End Sub
Public Sub Teardown() Implements IWorker.Teardown
' TODO: Close channel gracefully
End Sub
Private Sub SetOnlineState(NewState As Boolean)
If My.Application.Service.Online <> NewState Then
My.Application.Service.Online = NewState
RaiseEvent OnlineChanged(Me, NewState)
End If
End Sub
End Class
End Namespace