ConnectionStringsStorage.vb

Imports Microsoft.VisualBasic
Imports DevExpress.DashboardCommon
Imports DevExpress.DashboardWeb
Imports DevExpress.DataAccess.ConnectionParameters
Imports DevExpress.DataAccess.Json
Imports DevExpress.DataAccess.Web
Imports System
Imports System.Collections.Generic
Imports System.Configuration
Imports System.Data
Imports System.Data.Entity
Imports System.Linq

Namespace DXWebApplication26
    Public Class ConnectionStringsStorage
        Implements IDataSourceWizardConnectionStringsStorage
        Private Shared storage_Renamed As Dictionary(Of String, DataConnectionParametersBase)
        Private connectionString As String
        Private Shared ReadOnly Property Storage() As Dictionary(Of String, DataConnectionParametersBase)
            Get
                If storage_Renamed Is Nothing Then
                    storage_Renamed = New Dictionary(Of String, DataConnectionParametersBase)()
                End If
                Return storage_Renamed
            End Get
        End Property
        Public Sub New(ByVal connectionString As String)
            storage_Renamed = CreateNewStorage()
            Me.connectionString = connectionString
        End Sub

        Private Function CreateNewStorage() As Dictionary(Of String, DataConnectionParametersBase)
            Dim dictionary = New Dictionary(Of String, DataConnectionParametersBase)()

            ' Load existing SQL Connection Strings from Web.config
            For Each connectionStringSettings As ConnectionStringSettings In ConfigurationManager.ConnectionStrings
                dictionary.Add(connectionStringSettings.Name, New CustomStringConnectionParameters(connectionStringSettings.ConnectionString))
            Next connectionStringSettings

            ' Add predefined JSON connections
            Dim jsonConnectionParams = New JsonSourceConnectionParameters()
            jsonConnectionParams.JsonSource = New UriJsonSource(New Uri("https://raw.githubusercontent.com/DevExpress-Examples/DataSources/master/JSON/customers.json"))
            dictionary.Add("Customers_JSON", jsonConnectionParams)

            ' Load JSON connections from a DB
            Dim context As New JsonConnectionContext()
            context.Connections.ToList().ForEach(Sub(c)
                                                     If ((Not dictionary.ContainsKey(c.Name))) Then
                                                         dictionary.Add(c.Name, New CustomStringConnectionParameters(c.ConnectionString))
                                                     Else
                                                         dictionary(c.Name) = New CustomStringConnectionParameters(c.ConnectionString)
                                                     End If
                                                 End Sub)
            Return dictionary
        End Function

        Private Function GetConnectionDescriptions() As Dictionary(Of String, String) Implements IDataSourceWizardConnectionStringsProvider.GetConnectionDescriptions
            Return Storage.Keys.ToDictionary(Function(key) key, Function(value) value)
        End Function

        Private Function GetDataConnectionParameters(ByVal name As String) As DataConnectionParametersBase Implements IDataSourceWizardConnectionStringsProvider.GetDataConnectionParameters
            Return Storage(name)
        End Function

        ' Save JSON connections to a DB
        Private Sub SaveDataConnectionParameters(ByVal name As String, ByVal connectionParameters As DataConnectionParametersBase, ByVal saveCredentials As Boolean) Implements IDataSourceWizardConnectionStringsStorage.SaveDataConnectionParameters
            Dim jsonParams As JsonSourceConnectionParameters = TryCast(connectionParameters, JsonSourceConnectionParameters)
            If jsonParams IsNot Nothing Then
                Dim context As New JsonConnectionContext()
                Dim dataConnection As New JsonDataConnection(jsonParams.JsonSource)

                Dim existingConnection = context.Connections.Where(Function(c) c.Name = name).FirstOrDefault()
                If existingConnection Is Nothing Then
                    Dim jsonConnection As New MyJsonConnection()
                    jsonConnection.Name = name
                    jsonConnection.ConnectionString = dataConnection.CreateConnectionString()
                    context.Connections.Add(jsonConnection)
                Else
                    existingConnection.ConnectionString = dataConnection.CreateConnectionString()
                End If
                context.SaveChanges()

                Storage(name) = New CustomStringConnectionParameters(connectionString)
            End If
        End Sub
    End Class
End Namespace