Programming Microsoft Visual Basic .NET/Programming Microsoft Visual Basic .NET (Microsoft Press)(X08-78517)(2002).bin/setup/vbnet/26 web services/advancedws/sampleservice.asmx.vb

Text File | 2002-03-19 | 8.8 KB | 263 lines

' This web service contains a number of do-nothing methods
' whose purpose is to test advanced web service techniques,
' such as caching and soap extensions.

Imports System.Web.Services
Imports System.Web.Services.Protocols
Imports System.Net
Imports System.Threading
Imports System.Web.Security
Imports System.Xml.Serialization

<WebService(Description:="A web service with methods for doing tests", _
    Namespace:="http://www.vb2themax.com/")> _
Public Class SampleService
    Inherits System.Web.Services.WebService

#Region " Web Services Designer Generated Code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Web Services Designer.
        InitializeComponent()

        'Add your own initialization code after the InitializeComponent() call

    End Sub

    'Required by the Web Services Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Web Services Designer
    'It can be modified using the Web Services Designer.
    'Do not modify it using the code editor.
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        components = New System.ComponentModel.Container()
    End Sub

    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        'CODEGEN: This procedure is required by the Web Services Designer
        'Do not modify it using the code editor.
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

#End Region

    ' This method is useful to test cache behavior.

    <WebMethod(CacheDuration:=10)> _
    Function GetTime(ByVal arg As Integer) As Date
        Me.Application("GetTimeCounter") = GetTimeCounter() + 1
        Return Date.Now
    End Function

    ' this method returns the number of times the GetTime
    ' method has actually executed, so that you can check that
    ' if the method is cached, it isn't even reached by ASP.NET

    <WebMethod(Description:="The number of times GetTime has been called")> _
    Function GetTimeCounter() As Integer
        Dim o As Object = Me.Application("GetTimeCounter")
        If o Is Nothing Then
            Return 0
        Else
            Return CInt(o)
        End If
    End Function

    ' These two methods are used to test session state persistence.

    <WebMethod(Enablesession:=True)> _
    Function IncrementCounter() As Integer
        Dim o As Object = Session("counter")
        If o Is Nothing Then
            Session.Add("counter", 1)
        Else
            Session("counter") = CInt(o) + 1
        End If
        Return CInt(Session("counter"))
    End Function

    <WebMethod(Enablesession:=True)> _
    Function GetSessionID() As String
        Return Session.SessionID
    End Function

    ' this method is used to simulate a length method call

    <WebMethod(Description:="A lengthy method")> _
    Function LengthyMethodCall(ByVal seconds As Integer) As Integer
        ' wait for the specified number of seconds.
        System.Threading.Thread.Sleep(seconds * 1000)
        ' return the argument multiplied by 1000.
        Return seconds * 1000
    End Function

    ' this method is marked with the OneWay attribute

    <WebMethod(), SoapDocumentMethod(OneWay:=True)> _
    Sub OneWayLengthyMethodCall(ByVal seconds As Integer)
        ' wait for the specified number of seconds.
        System.Threading.Thread.Sleep(seconds * 1000)
    End Sub

    ' this method shows how you can have a method that returns
    ' an object that can be one of many concrete classes

    <WebMethod(), SoapRpcMethod(), SoapInclude(GetType(Invoice)), SoapInclude(GetType(PurchaseOrder))> _
    Function GetDocument(ByVal docname As String) As Document
        Select Case docname.ToLower
            Case "invoice"
                Return New Invoice()
            Case "purchaseorder"
                Return New PurchaseOrder()
        End Select
    End Function

    ' this method can be used to test Soap Exceptions

    <WebMethod()> _
    Sub ThrowAnException()
        Throw New NullReferenceException()
    End Sub

    ' This is the Public variable that will receive the userInfo header.
    Public userInfo As UserInfoHeader

    <WebMethod(), SoapHeader("userInfo", Required:=False)> _
    Function GetClientTime() As String
        ' Provide a default userInfo object if necessary.
        If userInfo Is Nothing Then
            userInfo = New UserInfoHeader()
        End If

        Dim serverTime As Date = Date.Now.ToUniversalTime
        Dim clientTime As Date = serverTime.AddHours(userInfo.TimeOffset)
        ' Creates a CultureInfo object with proper locale information.
        Dim ci As New System.Globalization.CultureInfo(userInfo.Culture)
        ' Return the time formatted using client's formatting rules.
        Return clientTime.ToString(ci)
    End Function

    Public accountInfo As AccountInfoHeader

    <WebMethod(), SoapHeader("accountInfo")> _
    Function ProtectedMethod() As Boolean
        ' Check that credentials are ok, throw exception if not.
        ValidateAccount()
        ' Return a value.
        Return True
    End Function

    <WebMethod(), SoapHeader("accountInfo")> _
    Function AnotherProtectedMethod() As Boolean
        ' Check that credentials are ok, throw exception if not.
        ValidateAccount()
        ' Return a value.
        Return True
    End Function

    ' validate username and password.
    Private Sub ValidateAccount()
        ' Throw exception if missing header.
        If accountInfo Is Nothing Then
            Throw New SoapException("Missing account header", SoapException.ClientFaultCode)
        End If

        ' Throw exception if header members aren't set.
        If accountInfo.UserName = "" Or accountInfo.Password = "" Then
            Throw New SoapException("Missing account info", SoapException.ClientFaultCode)
        End If

        ' Retrieve the subscription level of this user.
        Dim thisUserSubscriptionLevel As Integer
        thisUserSubscriptionLevel = GetUserSubscriptionLevel(accountInfo.UserName, accountInfo.Password)
        ' exit if credentials were invalid.
        If thisUserSubscriptionLevel < 0 Then
            Throw New SoapException("Unknown user", SoapException.ClientFaultCode)
        End If

        ' Retrieve the name of the method that called this procedure.
        Dim st As New System.Diagnostics.StackTrace(False)
        Dim sf As System.Diagnostics.StackFrame = st.GetFrame(1)
        Dim mb As System.Reflection.MethodBase = sf.GetMethod

        ' Retrieve the required subscription level for the calling method.
        Dim requiredSubscriptionLevel As Integer
        Select Case mb.Name
            Case "ProtectedMethod"
                requiredSubscriptionLevel = 1
            Case "AnotherProtectedMethod"
                requiredSubscriptionLevel = 2
        End Select

        ' Throw exception if subscription level isn't sufficient.
        If thisUserSubscriptionLevel < requiredSubscriptionLevel Then
            Throw New SoapException("Insufficient subscription level", SoapException.ClientFaultCode)
        End If
        ' Exit regularly if everything is ok.
    End Sub

    <WebMethod(), SoapCustomAuthentication(2), SoapHeader("accountInfo")> _
    Function YetAnotherProtectedMethod() As Boolean
        ' return a dummy value in this demo
        Return True
    End Function

End Class

Public Class Document
    Public [Date] As Date
    Public Number As Integer
End Class

Public Class Invoice
    Inherits Document
    Public Total As Decimal
End Class

Public Class PurchaseOrder
    Inherits Document
    Public AuthorizedBy As String
End Class

Public Class UserInfoHeader
    Inherits SoapHeader

    ' This object contains culture info for the user.
    Public Culture As String = ""
    ' this object contains the time difference from UTC time.
    Public TimeOffset As Single = 0

End Class

Public Class AccountInfoHeader
    Inherits SoapHeader

    Public UserName As String
    Public Password As String
End Class

Module AuthenticationFunctions

    ' Get user subscription level, or -1 if credentials are invalid.
    Function GetUserSubscriptionLevel(ByVal username As String, ByVal password As String) As Integer
        ' (A real application would use a database instead.)
        If username = "JoeDoe" And password = "jdpwd" Then
            Return 1
        ElseIf username = "AnnSmith" And password = "aspwd" Then
            Return 2
        Else
            ' unknown user or invalid credentials
            Return -1
        End If
    End Function
End Module