Question

Given the following modules:

adonetlib.psml

param($ModelModule)

$dbmodel=import-module $ModelModule -AsCustomObject 

function new-ADOnetconnection{
   return $dbmodel.newconnection()
}

mysqlmodel.psm1

function newconnection{
   write-host "MySQL connection"
}

sqlservermodel.psm1

function newconnection{
   write-host "SQLServer connection"
}

I’d like to be able to do this:

$mysql= import-module adonetlib -argumentlist mysqlmodel -ascustomobject
$sqlserver= import-module adonetlib -argumentlist sqlservermodel -ascustomobject

and have the following be true (sorry about the syntax):

$mysql."new-adonetconnection"() -> returns "MySql connection"
$sqlsever."new-adonetconnection"() -> returns "SQLServer connection"

Apparently, though, the adonetlib module is only loaded once (even though we imported it with different arguments). Both statements return “MySQL connection”.

Also,

get-module -all 

shows that the mysqlmodel module is loaded, but sqlservermodel isn’t.

Any ideas about how I can get this to work?

Answer 1

The functionality you’re looking for may be present already in the Powershell Community Extensions:

PS C:\Users\davidp> Get-command -Module pscx | ? { $_ -like "*-ado*" } | select name

Name
----
Get-ADObject
Get-AdoConnection
Get-AdoDataProvider
Invoke-AdoCommand

But in case you’re implementing just for fun:

You might be better off using submodules to implement the polymorphic behavior it looks like you’re trying to achieve. The top-level module would export a single New-ADOnetConnection cmdlet, with a parameter to select which DB you want to use for that connection; then it would dynamically choose which submodule to use to carry out the command.

If you’d like to avoid having to specify the DB on every call, you could create your own preference variable.