Auto Install

The error_handling.lss file I described in a previous post needs to be available on any machine where the script using it will execute. This is due to a weird behavior of the Notes engine when processing the %Include instruction: The inclusion is done at execution time if executing on a client and at compilation time if executing on a server.

It is certainly possible to distribute a file to all the users, explaining in which folder to copy it, but it is much simpler to have the same database that use it to install it whenever needed.

The HelpAbout document is a good place for storing a file. After attaching it, a HideWhen formula will prevent it from showing up to the user. Then a simple (Install error_handling.lss) agent will extract the file to the proper folder (if the folder doesn’t already have one). And the formula @Command( [RunAgent]; "(Install error_handling.lss)" ) in the PostOpen event of the Database Script library will run the agent each time the user opens the database.

Here is the code for the agent:

'Install error_handling.lss:

Option Public
Option Declare

Use "RegistryAccess"

Sub Initialize
    On Error Goto HandleError
    Goto EnterProc

HandleError:
    Error Err, Getthreadinfo( 1 ) & " : " & Erl & Chr$( 10 ) & Error$

EnterProc:

    Dim install As String
    install = "error_handling.lss"

    Dim notesFolder As String
    notesFolder = RegQueryValue( "HKEY_LOCAL_MACHINE", "SoftwareLotusNotes", "Path" )
    Dim path As String
    path = notesFolder & install
    If Dir$( path ) <> "" Then
        ' exit on library already installed
        Exit Sub
    End If

    Dim s As New NotesSession
    Dim db As NotesDatabase
    Set db = s.CurrentDatabase

    Dim d As notesdocument
    Set d = GetHelpAboutDocument( db )
    If d Is Nothing Then
        ' exit on library not available in the database
        Msgbox "The library " & install & " must be installed" & Chr( 10 ) _
        & "It's not in the database" & Chr( 10 ) _
        & "Contact the administrator of this database"
        Exit Sub
    End If

    Call ExtractAttachment( d, install, path )
    If Dir( path ) = "" Then
        ' exit on file not created
        Msgbox "The library " & install & " must be installed" & Chr( 10 ) _
        & "The file " & path & " couldn't be created" & Chr( 10 ) _
        & "Contact the administrator of this database"
        Exit Sub
    End If
    Print "Installed library " & install

    install = "error_handling_ui.lss"
    path = notesFolder & install
    Call ExtractAttachment( d, install, path )
    If Dir( path ) = "" Then
        ' exit on file not created
        Msgbox "The library " & install & " must be installed" & Chr( 10 ) _
        & "The file " & path & " couldn't be created" & Chr( 10 ) _
        & "Contact the administrator of this database"
        Exit Sub
    End If
    Print "Installed library " & install
End Sub

Function GetHelpAboutDocument( db As NotesDatabase ) As NotesDocument
    On Error Goto HandleError
    Goto EnterProc

HandleError:
    Error Err, Getthreadinfo( 1 ) & " : " & Erl & Chr$( 10 ) & Error$

EnterProc:

    Dim nc As NotesNoteCollection
    Set nc = db.CreateNoteCollection( False )
    nc.SelectHelpAbout = True
    Call nc.BuildCollection
    Dim nid As String
    nid = nc.GetFirstNoteId

    If nid <> "" Then
        Set GetHelpAboutDocument = db.GetDocumentByID( nid )
    Else
        Set GetHelpAboutDocument = Nothing
    End If
End Function

Sub ExtractAttachment( d As NotesDocument, filename As String, path As String )
    On Error Goto HandleError
    Goto EnterProc

HandleError:
    Error Err, Getthreadinfo( 1 ) & " : " & Erl & Chr$( 10 ) & Error$

EnterProc:

    If Not d.HasEmbedded Then Exit Sub

    Dim embedded As NotesEmbeddedObject
    Set embedded = d.GetAttachment( filename )
    If embedded Is Nothing Then Exit Sub

    Call embedded.ExtractFile( path )
End Sub

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