EDMIAPI: Add more database methods

Modules.EDMIAPI/DatabaseWithFallback.vb

@@ -53,6 +53,26 @@ Public Class DatabaseWithFallback
         _DatabaseIDB = DatabaseIDB
     End Sub
 
+    Public Function GetDatatableECM(pSQL As String, Optional pConnectionId As Integer = 0) As DataTable
+        Return GetDatatable(New GetDatatableOptions(pSQL, Constants.DatabaseType.ECM) With {
+            .ConnectionId = pConnectionId
+        })
+    End Function
+
+    Public Function GetDatatableIDB(pSQL As String, Optional pConnectionId As Integer = 0) As DataTable
+        Return GetDatatable(New GetDatatableOptions(pSQL, Constants.DatabaseType.IDB) With {
+            .ConnectionId = pConnectionId
+        })
+    End Function
+
+    Public Function GetScalarValueECM(pSQL As String, Optional pConnectionId As Integer = 0) As Object
+        Return GetScalarValue(pSQL, Constants.DatabaseType.ECM, pForceFallback:=False, pConnectionId)
+    End Function
+
+    Public Function GetScalarValueIDB(pSQL As String, Optional pConnectionId As Integer = 0) As Object
+        Return GetScalarValue(pSQL, Constants.DatabaseType.IDB, pForceFallback:=False, pConnectionId)
+    End Function
+
     ''' <summary>
     ''' Returns a Datatable by trying to fetch a cached version from the service, then querying the database through the service and querying the database directly as fallback. 
     ''' </summary>
@@ -96,14 +116,14 @@ Public Class DatabaseWithFallback
                 Return GetDatatableFromDatabase(pFallbackSQL, pFallbackType, pConnectionId)
             End If
 
-            ' If the table is not cached, we go to database immediately
+            ' If the table is not cached, we try going through the service
             If Not IsTableCached(pDataTableName) Then
-                Return GetDatatableFromDatabase(pFallbackSQL, pFallbackType, pConnectionId)
+                Return GetDatatableFromService(pFallbackSQL, pFallbackType, pConnectionId)
             End If
 
-            ' If there is a proper ConnectionId, we go to database immediately
+            ' If there is a proper ConnectionId, we try going through the service
             If pConnectionId > 0 Then
-                Return GetDatatableFromDatabase(pFallbackSQL, pFallbackType, pConnectionId)
+                Return GetDatatableFromService(pFallbackSQL, pFallbackType, pConnectionId)
             End If
 
             Try
@@ -127,6 +147,37 @@ Public Class DatabaseWithFallback
         End Try
     End Function
 
+    ''' <summary>
+    ''' Returns a Scalar Value by querying the database through the service and querying the database directly as fallback.
+    ''' </summary>
+    ''' <param name="pSQL">SQL Command to execute as fallback</param>
+    ''' <param name="pDatabaseType">Named Database to use for the fallback SQL Command</param>
+    ''' <param name="pForceFallback">Force the fallback, skipping the service completely</param>
+    ''' <param name="pConnectionId">Connection Id to use, references TBDD_CONNECTION</param>
+    Public Function GetScalarValue(pSQL As String, pDatabaseType As Constants.DatabaseType, Optional pForceFallback As Boolean = False, Optional pConnectionId As Integer = 0) As DataTable
+        Try
+            Dim oResult As DataTable = Nothing
+            Dim oTableResult As TableResult = Nothing
+
+            ' If there is no client, we assume there is no service (configured)
+            If _Client Is Nothing Then
+                Return GetScalarValueFromDatabase(pSQL, pDatabaseType, pConnectionId)
+            End If
+
+            ' If ForceFallback flag is set, we go to database immediately
+            If pForceFallback Then
+                Return GetScalarValueFromDatabase(pSQL, pDatabaseType, pConnectionId)
+            End If
+
+            Return GetScalarValueFromService(pSQL, pDatabaseType, pConnectionId)
+
+        Catch ex As Exception
+            _Logger.Error(ex)
+            Return Nothing
+
+        End Try
+    End Function
+
     Private Function IsTableCached(pName As String) As Boolean
         If _Client Is Nothing Then
             Return False
@@ -135,14 +186,76 @@ Public Class DatabaseWithFallback
         Return _Client.CachedTables.Contains(pName.ToUpper)
     End Function
 
-    Private Function GetDatatableFromDatabase(SQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer)
+    Private Function GetDatatableFromService(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer)
         Try
             Select Case DatabaseType
                 Case Constants.DatabaseType.ECM
-                    Return _DatabaseEDM.GetDatatable(SQLCommand)
+                    Return _Client.GetDatatableFromECM(pSQLCommand, pConnectionId)
 
                 Case Constants.DatabaseType.IDB
-                    Return _DatabaseIDB.GetDatatable(SQLCommand)
+                    Return _Client.GetDatatableFromIDB(pSQLCommand, pConnectionId)
+
+                Case Else
+                    Return Nothing
+
+            End Select
+        Catch ex As Exception
+            _Logger.Warn("GetDatatableFromService failed. Falling back to direct database access.")
+            _Logger.Error(ex)
+            Return GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
+
+        End Try
+    End Function
+
+    Private Function GetScalarValueFromService(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer)
+        Try
+            Select Case DatabaseType
+                Case Constants.DatabaseType.ECM
+                    Return _Client.GetScalarValueFromECM(pSQLCommand, pConnectionId)
+
+                Case Constants.DatabaseType.IDB
+                    Return _Client.GetScalarValueFromIDB(pSQLCommand, pConnectionId)
+
+                Case Else
+                    Return Nothing
+
+            End Select
+        Catch ex As Exception
+            _Logger.Warn("GetScalarValueFromService failed. Falling back to direct database access.")
+            _Logger.Error(ex)
+            Return GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
+
+        End Try
+    End Function
+
+    Private Function GetDatatableFromDatabase(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer)
+        Try
+            Select Case DatabaseType
+                Case Constants.DatabaseType.ECM
+                    Return _DatabaseEDM.GetDatatable(pSQLCommand)
+
+                Case Constants.DatabaseType.IDB
+                    Return _DatabaseIDB.GetDatatable(pSQLCommand)
+
+                Case Else
+                    Return Nothing
+
+            End Select
+        Catch ex As Exception
+            _Logger.Error(ex)
+            Return Nothing
+
+        End Try
+    End Function
+
+    Private Function GetScalarValueFromDatabase(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer)
+        Try
+            Select Case DatabaseType
+                Case Constants.DatabaseType.ECM
+                    Return _DatabaseEDM.GetScalarValue(pSQLCommand)
+
+                Case Constants.DatabaseType.IDB
+                    Return _DatabaseIDB.GetScalarValue(pSQLCommand)
 
                 Case Else
                     Return Nothing