About Providers

Short description

Describes how PowerShell providers provide access to data and components that would not otherwise be easily accessible at the command line. The data is presented in a consistent format that resembles a file system drive.

Long description

PowerShell providers are Microsoft .NET Framework-based programs that make the data in a specialized data store available in PowerShell so that you can view and manage it.

The data that a provider exposes appears in a drive, and you access the data in a path like you would on a hard disk drive. You can use any of the built-in cmdlets that the provider supports to manage the data in the provider drive. And, you can use custom cmdlets that are designed especially for the data.

The providers can also add dynamic parameters to the built-in cmdlets. These are parameters that are available only when you use the cmdlet with the provider data.

Built-in providers

PowerShell includes a set of built-in providers that you can use to access the different types of data stores.

Provider Drive Data store
Alias Alias: PowerShell aliases
Certificate Cert: x509 certificates for digital signatures
Environment Env: Windows environment variables
FileSystem (*) File system drives, directories, and files
Function Function: PowerShell functions
Registry HKLM:, HKCU: Windows registry
Variable Variable: PowerShell variables
WSMan WSMan: WS-Management configuration information

(*) The FileSystem drives vary on each system.

You can also create your own PowerShell providers, and you can install providers that others develop. To list the providers that are available in your session, type:

Get-PSProvider

Installing and removing providers

Providers are typically installed via PowerShell modules. Importing the module loads the provider into your session. You cannot uninstall the built-in providers. You can uninstall providers loaded by other modules.

You can unload a provider from the current session. You can do this by using the Remove-Module cmdlet. This cmdlet does not uninstall the provider, but it makes the provider unavailable in the session.

You can also use the Remove-PSDrive cmdlet to remove any drive from the current session. This data on the drive is not affected, but the drive is no longer available in that session.

Viewing providers

To view the PowerShell providers on your computer, type:

Get-PSProvider

The output lists the built-in providers and the providers that you added to the session.

The provider cmdlets

The following cmdlets are designed to work with the data exposed by any provider. You can use the same cmdlets in the same way to manage the different types of data that providers expose. After you learn to manage the data of one provider, you can use the same procedures with the data from any provider.

For example, the New-Item cmdlet creates a new item. In the C: drive that is supported by the FileSystem provider, you can use New-Item to create a new file or folder. In the drives that are supported by the Registry provider, you can use New-Item to create a new registry key. In the Alias: drive, you can use New-Item to create a new alias.

For detailed information about any of the following cmdlets, type:

Get-Help <cmdlet-name> -Detailed

ChildItem cmdlets

Content Cmdlets

Item Cmdlets

ItemProperty cmdlets

Location cmdlets

Path cmdlets

PSDrive cmdlets

PSProvider Cmdlets

Viewing provider data

The primary benefit of a provider is that it exposes its data in a familiar and consistent way. The model for data presentation is a file system drive.

To use data that the provider exposes, you view it, move through it, and change it as though it were data on a hard drive. Therefore, the most important information about a provider is the name of the drive that it supports.

The drive is listed in the default display of the Get-PSProvider cmdlet, but you can get information about the provider drive by using the Get-PSDrive cmdlet. For example, to get all the properties of the Function: drive, type:

Get-PSDrive Function | Format-List *

You can view and move through the data in a provider drive just as you would on a file system drive.

To view the contents of a provider drive, use the Get-Item or Get-ChildItem cmdlets. Type the drive name followed by a colon (:). For example, to view the contents of the Alias: drive, type:

Get-Item alias:

You can view and manage the data in any drive from another drive by including the drive name in the path. For example, to view the HKLM\Software registry key in the HKLM: drive from another drive, type:

Get-ChildItem HKLM:\SOFTWARE\

To open the drive, use the Set-Location cmdlet. Remember the colon when you specify the drive path. For example, to change your location to the root directory of the Cert: drive, type:

Set-Location cert:

Then, to view the contents of the Cert: drive, type:

Get-ChildItem

Moving through hierarchical data

You can move through a provider drive just as you would a hard disk drive. If the data is arranged in a hierarchy of items within items, use a backslash (\) to indicate a child item. Use the following format:

drive:\location\child-location\...

For example, to change your location to the HKLM\Software registry key, type a Set-Location command, such as:

Set-Location HKLM:\SOFTWARE\

You can also use relative references to locations. A dot (.) represents the current location. For example, if you are in the HKLM:\Software\Microsoft registry key, and you want to list the registry subkeys in the HKLM:\Software\Microsoft\PowerShell key, type the following command:

Get-ChildItem .\PowerShell

Provider Home

Providers also have a Home location. This location is shared by all PSDrives backed by the provider. It can be retrieved by viewing the Home property of the provider.

Get-PSProvider | Format-Table Name, Home
Name        Home
----        ----
Registry
Alias
Environment
FileSystem  C:\Users\robreed
Function
Variable
Certificate

The FileSystem provider is the only provider that has a default value for Home. It is the same value as $Home see about_Automatic_Variables.

You can set the Home directory for a provider, for the current session, using its property.

(Get-PSProvider FileSystem).Home = "C:\"

The ~ character can be used to represent the provider's home directory. If the provider does not have a Home location set, you will see an error.

Cert:\> Set-Location ~
Set-Location : Home location for this provider is not set. To set the home
location, call "(get-psprovider 'Certificate').Home = 'path'".
At line:1 char:1
+ Set-Location ~
+ ~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [Set-Location],
                              PSInvalidOperationException
...

Finding dynamic parameters

Dynamic parameters are cmdlet parameters that are added to a cmdlet by a provider. These parameters are available only when the cmdlet is used with the provider that added them.

For example, the Cert: drive adds the CodeSigningCert parameter to the Get-Item and Get-ChildItem cmdlets. You can use this parameter only when you use Get-Item or Get-ChildItem in the Cert: drive.

For a list of the dynamic parameters that a provider supports, see the Help file for the provider. Type:

Get-Help <provider-name>

For example:

Get-Help certificate

Learning about providers

Although all provider data appears in drives, and you use the same methods to move through them, the similarity stops there. The data stores that the provider exposes can be as varied as Active Directory locations and Microsoft Exchange Server mailboxes.

For information about individual PowerShell providers, type:

Get-Help <ProviderName>

For example:

Get-Help registry

For a list of Help topics about the providers, type:

Get-Help * -Category Provider

See also

about_Locations

about_Path_Syntax