Tech Tip  -  Extractor Document Summarization Web Service

What is it?

The Extractor Web Service is a web API built in Visual Studio .NET that wraps the Extractor Engine to allow developers to integrate text summarization functionality quickly and easily into their applications.

Why would I want to use it?

The ability to read a document and capture its key words and phrases is a necessity when evaluating, comparing, and cataloging documents.  Typically key word/phrase extraction requires the reading of the document in order to glean the intent or topics being presented and the subsequent capture (keying) of the key words and phrases into a data store.  Extractor reads documents and returns the key words and phrases with a very high accuracy, removing the need for human involvement.

How do I use it?

1.       Obtain an Application ID from DBI Sales.

2.       Create a new project, in this case we will build a VB.NET Winforms project.

3.       In the Solution Explorer right click on the References node and select "Add Service Reference".

4.       In the Address field enter  …
http://www.picofocus.com/DemoEngine/dbiExtractorDemoWebService.asmx

5.       Click the Go button and the service will be discovered and listed in the services box on the left of the dialog.

6.       Change the Namespace from the default to dbiExtractorWS  and press the OK button.

Your project will now include a Service References node under which the dbiExtractorWS is listed.

7.       In your form add 2 text boxes with their Multiline property set to True and the Scrollbars set to Vertical.   Name the first TextBox Extractee, and the second TextBox Extraction.  Add a Button to the form and name it ExtractText.

8.       In the ExtactText_Click Event add the following code …

 Private Sub ExtractText_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExtractText.Click

        Dim xTractee As New Xml.XmlDocument

        Dim xTraction As New Xml.XmlDocument

        Dim xTractionNode As Xml.XmlNode

        Dim resultNodes As Xml.XmlNodeList

        Dim xtractorStatus As String

        'Set the properties of the Extraction Request ...

        xTractee.LoadXml("<ExtractionRequest " & _

                         "ActivateHTML=""OFF"" " & _

                         "ActivateEmail=""OFF"" " & _

                         "PhrasesRequested=""10"" " & _

                         "LanguageID=""1"" " & _

                         "CharCodeID=""1"">" & _

                         "<EXTRACTEE >" & _

                         Me.Extractee.Text & _

                         "</EXTRACTEE>" & _

                         "</ExtractionRequest>")

        'Process the Extraction Request.

        'NOTE: Web Services by nature marshal  XML Documents as XML Nodes.

        '      Pass in the first (and only) node in the document to the web service.

        'NOTE: Place your unique Application ID in the call below.

        xTractionNode = Xtractor.ProcessXtraction("<Application ID From DBI>", xTractee.FirstChild)

        'Place the returned XML Node into the xTraction Document.

        xTraction.AppendChild(xTraction.ImportNode(xTractionNode, True))

        'Check the status of the Extraction Request

        xtractorStatus = xTractionNode.Attributes("ExtractionStatus").Value

        If xtractorStatus = "1" Then    'Extraction Successful

            'Get all of the Result Nodes.

            'NOTE:  In the Extraction Request above we set PhrasesRequested to 10.

            resultNodes = xTraction.GetElementsByTagName("Result")

            'Iterate through the Result Nodes and print out the Key Phrases and Highlights.

            Dim resultNode As Xml.XmlNode

            For Each resultNode In resultNodes

                Me.Extraction.Text = Me.Extraction.Text & _

                                                      "Key Word/Phrase: " & resultNode.Item("KeyPhrase").InnerText & vbCrLf & _

                                                      "Highlight: " & resultNode.Item("KeyHighlight").InnerText & vbCrLf & vbCrLf

           Next ‘ResultNode

        Else

            Me.Extraction.Text = "Error Encountered" & vbCrLf & vbCrLf

            Me.Extraction.Text = Me.Extraction.Text & vbCrLf & "Extractor returned a code of " + xtractorStatus

            Me.Extraction.Text = Me.Extraction.Text & vbCrLf & vbCrLf & xTractionNode.InnerText

        End If

    End Sub

9.       Run the application.  Copy and Paste some text into the Extractee Text Box. 
NOTE;  The application is requesting 10 Key Words/Phrases so make sure you have enough text to reasonable expect 10 themes or topics to be returned.

10.   Press the ExtractText button to request and present the extraction of the text entered in the Extractee Text Box.

11.   If no errors are encountered the Extraction Text Box will display the top ten Key Words and Phrases from your text along with a highlight (sentence) from the original text illustrating  the most prominent use of the key word or phrase within the document.

Summary

The application described above is a simple implementation of the Extractor Content Summarization Web Service which only touches the surface of the power of the Extractor component software.  For more information on Extractor, the Extractor Web Service, and the potential of Extractor for your specific development needs please visit www.Extractor.com or contact dbi Sales via email through sales@dbi-tech.com.