BizTalk 2006 : Dealing with Compressed Files (part 1) - Sending Simple Zipped Files

A common problem that most BizTalk projects encounter is having to either send or receive compressed data in the formof a ZIP file. Often, the incoming ZIP file has multiple entries, each of which need to be submitted to BizTalk. In most cases, these files are XML files, but in some situations, they can be either flat files or binary files instead. The examples in the following sections outline a potential simplified solution for sending and receiving zipped information. Additionally, you'll get a chance to explore ways to augment the solution using new functionality within BizTalk.

Sending Simple Zipped Files

In order to send a ZIP file from BizTalk, you will need to create a custom send pipeline and a custom encoding pipeline component. The pipeline component will be responsible for examining the incoming message, getting access to the message's data, compressing it, and returning it to BizTalk. The simplest scenario is the "single message in/single message out" scenario. Here, a message is sent to the send pipeline, it is compressed, and a single message is sent out. The pipeline component required for this is documented in the following class:

Imports Microsoft.VisualBasic
Imports System
Imports System.ComponentModel
Imports System.Collections
Imports System.Diagnostics
Imports System.Drawing
Imports System.IO
Imports System.Reflection
Imports Microsoft.BizTalk.Component.Interop
Imports Microsoft.Utility.PipelinePropertyAttribute
Imports ICSharpCode.SharpZipLib.Zip

Namespace ABC.BizTalk.PipelineComponents
    <ComponentCategory(CategoryTypes.CATID_PipelineComponent),_
ComponentCategory(CategoryTypes.CATID_Encoder),_
System.Runtime.InteropServices.Guid("56C7B68B-F288-4f78-A67F-20043CA4943E")> _

    Public Class ZipEncodingComponent
        Implements IBaseComponent, Microsoft.BizTalk.Component.Interop.IComponent,_
Microsoft.BizTalk.Component.Interop.IPersistPropertyBag, IComponentUI
        Private resourceManager As System.Resources.ResourceManager = New_
System.Resources.ResourceManager("ABC.BizTalk.PipelineComponents",_
System.Reflection.Assembly.GetExecutingAssembly())
        Private _compressionlevel As String
        Private _filename As String
        Private _password As String

					  

Private Const DEFAULT_COMPRESSIONLEVEL_TEXT As String = "5"
        Private Const DEFAULT_COMPRESSIONLEVEL As Integer = 5
        Private Const DEFAULT_FILENAME As String = "ABCBizTalkSendFile"


#Region "IBaseComponent"
        <Browsable(False)> _
        Public ReadOnly Property Name() As String
            Get
               Return "ZIP encoding component"
            End Get
        End Property
        <Browsable(False)> _
        Public ReadOnly Property Version() As String
            Get
                Return "1.0"
            End Get
        End Property
        <Browsable(False)> _
        Public ReadOnly Property Description() As String
            Get
                Return "Pipeline Component which will encode an outgoing_
                message as a ZIP file."
            End Get
        End Property
        <Browsable(False)> _
        Public ReadOnly Property Icon() As System.IntPtr
            Get
                Return (CType(resourceManager.GetObject("IconBitmap"),_
Bitmap)).GetHicon()
            End Get
        End Property
#End Region

        Public Property Password() As String
            Get
                Return _password
            End Get
            Set(ByVal value As String)
                _password = value
            End Set
        End Property

					  

Public Property Filename() As String
            Get
                Return _filename
            End Get
            Set(ByVal value As String)
                _filename = value
            End Set
        End Property


        Public Property CompressionLevel() As String
            Get
                Return _compressionlevel
            End Get
            Set(ByVal value As String)
                _compressionlevel = value
            End Set
        End Property

        Private Function Encode(ByVal inStream As Stream) As Stream
            Dim outStream As Stream = inStream
            Dim inFile As String = Path.GetTempFileName()
            Dim outFile As String = Path.ChangeExtension(inFile, "zip")

            Try
                 Dim zipStream As ZipOutputStream = New_
 ZipOutputStream(File.Create(outFile))

                 ' get password, if supplied
                 If _password.IsNullOrEmpty Then
                     zipStream.Password = _password
                 End If

                 ' get compression level, if supplied
                 Dim compressionlevel As Integer = DEFAULT_COMPRESSIONLEVEL
                 If (Not _compressionlevel Is Nothing) AndAlso (_compressionlevel <>_
"") Then
                     compressionlevel = Convert.ToInt32(_compressionlevel)
                 End If
                 If (compressionlevel < 0) OrElse (compressionlevel > 9) Then
                     compressionlevel = DEFAULT_COMPRESSIONLEVEL
                 End If
                 zipStream.SetLevel(compressionlevel)

					  

' get message filename, if supplied
                 Dim filename As String
                 If ((Not _filename Is Nothing) AndAlso (_filename <> "")) Then
                     filename = (_filename)
                 Else
                     filename = (DEFAULT_FILENAME)
                 End If
                 Dim entry As ZipEntry = New ZipEntry(filename)
                 zipStream.PutNextEntry(entry)

                 ' copy the input into the compressed output stream
                 Dim buffer As Byte() = New Byte(4095) {}
                 Dim count As Integer = inStream.Read(buffer, 0, buffer.Length 0)
                 Do While (count <> 0)
                      zipStream.Write(buffer, 0, count)
                      count = inStream.Read(buffer, 0, buffer.Length 0)

                 Loop
                 zipStream.Finish()
                 zipStream.Close()

                 outStream = ReadFileToMemoryStream(outFile)
             Catch ex As Exception
                 System.Diagnostics.Debug.WriteLine(ex)
             Finally
                 If File.Exists(inFile) Then
                     File.Delete(inFile)
                 End If

                 If File.Exists(outFile) Then
                     File.Delete(outFile)
                 End If
             End Try

             Return outStream
         End Function

#Region "IPersistPropertyBag Members"

         Public Sub InitNew()
         End Sub

         Public Sub GetClassID(<System.Runtime.InteropServices.Out()> ByRef_
         classID As Guid)
             classID =  New Guid("0F94CF83-0B04-49a6-B73C-70473E0CF96F")
         End Sub

					  

Public Sub Load(ByVal propertyBag As IPropertyBag, ByVal errorLog_
         As Integer)

            Dim value As String

            value = Convert.ToString((ReadPropertyBag(propertyBag, "Password")))
            If Not value Is Nothing Then
                _password = value
            End If
            value = Convert.ToString((ReadPropertyBag(propertyBag, "Filename")))
            If Not value Is Nothing Then
                _filename = value
            End If
            value = Convert.ToString(ReadPropertyBag(propertyBag,_
            "CompressionLevel"))

            If Not value Is Nothing Then
                _compressionlevel = value
            End If
        End Sub

        Public Sub Save(ByVal propertyBag As IPropertyBag, ByVal clearDirty As_
Boolean,  ByVal saveAllProperties As Boolean)
             Dim value As String

             value = Convert.ToString(_password)
             WritePropertyBag(propertyBag, "Password", value)

             value = Convert.ToString(_filename)
             WritePropertyBag(propertyBag, "Filename", value)

              value = Convert.ToString(_compressionlevel)
              WritePropertyBag(propertyBag, "CompressionLevel", value)

        End Sub

#End Region

#Region "IComponent Members"

					  

Public Function Execute(ByVal pContext As IPipelineContext, ByVal pInMsg As_
Microsoft.BizTalk.Message.Interop.IBaseMessage) As_
Microsoft.BizTalk.Message.Interop.IBaseMessage
            If Not pInMsg Is Nothing Then
            Dim originalStream As Stream = _
pInMsg.BodyPart.GetOriginalDataStream()
                pInMsg.BodyPart.Data = Encode(originalStream)
                pContext.ResourceTracker.AddResource(pInMsg.BodyPart.Data)
            End If

            Return pInMsg
       End Function

#End Region

#Region "IComponentUI Members"

        ' <summary>
        'The Validate method is called by the BizTalk Editor during the build
        'of a BizTalk project.
        ' </summary>
        '<param name="obj">An Object containing the configuration
        'properties.</param>
        '<returns>The IEnumerator enables the caller to enumerate through a
        'collection of strings containing error messages. These error messages
        'appear 'as compiler error messages. To report successful property
        'validation, the method should return an empty enumerator.</returns>
        Public Function Validate(ByVal projectSystem As Object) As IEnumerator
            ' example implementation:
            ' ArrayList errorList = new ArrayList();
            ' errorList.Add("This is a compiler error");
            ' return errorList.GetEnumerator();
            Return Nothing
        End Function
        Public Shared Function ReadFileToMemoryStream(ByVal fromFilename _
        As String) As MemoryStream
            Dim file As FileStream = Nothing
            Try
                file = New FileStream(fromFilename, System.IO.FileMode.Open)
                Dim memStream As MemoryStream = New MemoryStream()
                Dim tmpBuff As Byte() = New Byte(4095) {}
                Dim bytesRead As Integer = 0
                bytesRead = file.Read(tmpBuff, 0, tmpBuff.Length)
                memStream.Write(tmpBuff, 0, bytesRead)

					  

Do While bytesRead <> 0
                bytesRead = file.Read(tmpBuff, 0, tmpBuff.Length)
                memStream.Write(tmpBuff, 0, bytesRead)
             Loop

             file.Close()
             file = Nothing

             memStream.Position = 0
             Return memStream
         Finally
             If Not file Is Nothing Then
                 file.Close()
             End If
         End Try
     End Function

#End Region

#Region "Private Helpers"

         Public Shared Function ReadPropertyBag(ByVal pb As_
         Microsoft.BizTalk.Component.Interop.IPropertyBag, ByVal propName As_
         String) As Object
            Dim value As Object
            value = Nothing

            Try
                pb.Read(propName, value, 0)

            Catch argException As ArgumentException
                Return value

            Catch ex As Exception
                Throw New ApplicationException(ex.Message)
            End Try

            Return value
        End Function
        ''' <summary>
        ''' Writes property values into a property bag.

        ''' </summary>        ''' <param name="pb">Property bag.</param>
        ''' <param name="propName">Name of property.</param>
        ''' <param name="val">Value of property.</param>
        Public Shared Sub WritePropertyBag(ByVal pb As _

					  

Microsoft.BizTalk.Component.Interop.IPropertyBag, ByVal propName As _
String, ByVal val As Object)
           Try
               pb.Write(propName, val)
           Catch ex As Exception
               Throw New ApplicationException(ex.Message)
           End Try
       End Sub
#End Region
    End Class
End Namespace