How do I create a RESTful API in PowerShell?
Why oh why would anyone want to do this?
Recently I was building a web front-end in AngularJS and NodeJS, and desperately wanted to use native
PowerShell to query Active Directory as well as leverage the get-WMIObject cmdlet to extract data from
Microsoft servers in real-time. And while there are PowerShell modules for NodeJS, they are quite limited in
what they can do.
So, rather than work with the limited functionality of a NodeJS plugin I decided to build my own RESTful API
that would execute any command I want and return the resultant data as JSON objects.
The end result will be a dynamically customizable set of URLs that the API server can interpret, process and
return data.
This script (running on server named ‘apiserver’) is going to be set to receive requests in the following format:
http://apiserver:8000/commandtype/parameter1/parameter2
In the specific case of using this API to query any WMI Class on any server, the format is more accurately
described as:
http://apiserver:8000/wmi/win32_class/server_name
So if I wanted to get the win32_bios WMI class data for server DC01, I would issue a GET request to:
http://apiserver:8000/wmi/win32_bios/dc01
Or if I wanted to get data from a different class, like win32_operatingsystem, it would be:
http://apiserver:8000/wmi/win32_operatingsystem/dc01
(you see how we should be able to sub-in any win32 class and server name to dynamically get the data we need)
Here is the code to make it happen. The comments should be self-explanatory (enough for you to be able to
modify it to suit your needs):
WARNING – the following code should not be implemented in a production environment without careful
consideration of things like:
– Code Injection
– Permissions
– Other scary stuff