Filters are used by Microsoft Business Connectivity Service (BCS) to give values to input parameters while invoking a Method on the External System (LobSystem). But there could be some parameters whose values should be provided by the system (example: username, password) and not from the user. Filters that provide values to these input parameters are called System Filters.
Here is an example Scenario of when to use System Filter: Jim has a web service operation that creates a file. The method takes filename, user name, and password. File name will be passed as user input, but username and password will have to be passed from the system. Jim needs a solution to pass these values without requesting them from the user.
Solution: Jim will have to configure username and password filters for the parameters that match username and password. Jim will also have to specify the “SecondarySSOApplicationID” and “SSOProviderImplementation” on the External System Instance, which will be used by the filters to fetch username and password values. This will make the system provide username and password as values to input parameters.
The different types of System Filters that are supported are:
System Filters can be configured for input parameters via SPD. The steps to configure System Filters via SPD are:
System Filters can be configured by making changes to the model file by hand. The steps to follow to configure System Filters are:
<Parameter Direction="In" ...> <!-- properties omitted –> <TypeDescriptor FilterName="NameofSsoTicketFilter" ...> <!-- properties omitted –> </TypeDescriptor> </Parameter>
- Tittu Jose, Software Development Engineer