Using DCOM as an alternative to IIS for Forest & Trees

Products

• Cleverpath Reporter

Issue/Introduction

MS Remote Data Service can currently be used with Forest & Trees as a method of querying databases over a network. MS Internet Information Server has to be installed on a Windows NT or 2000 server, and F&T can then query any datasource that is available on that server. For added functionality within F&T, the F&T business objects can be installed on the server so that F&T can obtain a list of datasources, tables and columns that are available.

What if there is no IIS available on a remote server but you have the F&T business objects (F&T RDS components from F&T install disk), how could you access remote data that is available on the server?

 

Environment

Release: CVPFTB05900-6.51-Forest & Trees-Dashboard Option Component
Component:

Resolution

Instead of using Remote Data Service (RDS) via IIS to query remote data sources over an intranet/internet, it is possible to use the Distributed Component Object Model (DCOM) as an alternative method of communication. DCOM is that part of the Component Object Model (COM) implementation that allows COM components to communicate over a network.

The Forest & Trees RDS business objects can be packaged to look and behave as COM objects and can then be used like any other COM object locally or across a network via DCOM. Here follows a step-by-step guide to getting a server to work with DCOM instead of IIS and then accessing the data using the RDS Interface in F&T.

Steps required on the server:

1. Install the F&T business objects.
2. Open the Component Services administration tool from Start->Programs->Administration Tools->Component Services.
3. Navigate down to the COM+ Applications folder, right click and create a new application.
4. Click Next, and click 'Create an empty application'
5. Give it a name say 'Forest and Trees COM package' and select 'Server application' and click next.
6. Select interactive user, click next and then click finish.
7. Navigate to the Components folder below 'Forest and Trees COM package' right click and click New->Component.
8. The component install wizard will appear. Click next, and click Import components that are already registered.
9. From the list choose RDSServer.Datafactory, click next and finish.
10. Navigate to the Components folder below 'Forest and Trees COM package' right click and click New->Component.
11. The component install wizard will appear. Click next, and click Install New ->Component.
12. Navigate to where the F&T business objects were installed, typically C:\Program Files\Common Files\System\msadc, and select ftwrdiis.dll and click open.
13. Two new components will appear in the list and then click Add.
14. Select FtwRdItr.DLL and click open.
15. A total three components should now be in the list, dbEnum.dbEnum, ftwrdiis.dbEnumSvr and ftwrdiis.Tables. If this is correct click next and finish and the server setup is now complete.

Steps required on the F&T client machine:

1. Install the F&T business objects.
2. Start F&T and create a new Table View with an MS RDS interface.
3. Right click on the view and select database.
4. Enter the machine hostname in the server field. Note do not proceed the name with (http:// or any other protocol) as you would when using RDS with IIS.
5. Enter the username and password of a user on the server.
6. Click the question mark next to the database field, and a list of datasources should appear.

The setup is now complete, and the RDS interface can now be used to access datasources on the server, except on the server the method used to transport the data is DCOM and not IIS. The only difference that the F&T user sees on the client is the necessity to use a username and password, and there is no protocol required when specifying the hostname.

The benefit of this is that there is no need to have an IIS server, the inbuilt COM functionality of Windows can be utilised at no extra cost.