Automation of creating and validing tokens when working with the AxM API based on the script provided by Bart Reardon

To find out more about this project check out the post "Automating Token Generation for Apple School Managers New API" on my blog CantScript.com

1. A Script that only deals with creating the Client Assertion
2. Saves the Client Assertion to a text file, along with a date/time stamp 180 days later
3. A second Script that only handle the creation of the Access Token
4. Saves the Access Token to a text file, along with a timestamp 60 mins later
5. Should an Access Token not exist, the second script will create an Access Token providing the Client Assertion is still valid based on its date/time stamp
6. Should there be an Access Token but its not valid based on its timestamp, the second script will create a new valid Access Token, again providing the Client Assertion is still valid based on its date/time
7. Enables two lines of code in the actual API script that creates/checks/renews the Access Token and saves the value into a variable for use in that script

This is all contained in a folder structure so as long as you add the scripts that interact with the API in the root of this folder, you only need to add the values you need from Axm to the Create Client Assertion and Create Access Token scripts once and no other variables are needed to make the automation work.

First things first, if you haven't already go and read Barts blog so that you know how to configure ASM. From ASM you'll need

• The Private Key File which will end in .pem
  
• Client ID
  
• Key ID

Step 1

• Download the AxM_API folder from the GitHun repo.

It doesn't matter where this folder lives on the device as long as you know where you keep it as this is going to become the working folder for all of your ASM API scripts

Step 2
Take your Private Key File and move it into the AxM-API/AxMCert folder

Step 3

• Open AxM-API/AutomationScript/create_client_assertion.sh in a text/code editor
  
• Enter the name of your Private Key File (so for example myPrivateKey.pem, not the location of the file) into the private_key_file variable
  
• Enter your Client ID into the client_id variable
  
• Enter your Key ID into the key_id variable
  
• Save and close

Step 4

• Open AxM-API/AutomationScript/create_access_token.sh in a text/code editor
  
• Enter your Client ID into the client_id variable
  
• Comment out either scope="school.api" or scope="business.api" depending on if you are interacting with ASM or ABM
  
• Save and close

Step 5

• Run AxM-API/AutomationScript/create_client_assertion.sh

Any script that you want to use that interacts with the AxM API needs save to the root of the AxM_API folder.

I've given a simple example script within the AxM_API folder.

Your scripts just need the following two lines at the top

./AutomationScripts/create_access_token.sh
accessToken=$(awk -F': ' '/^AccessToken:/ {print $2}' ./Tokens/access_token_format.txt)

Then you will use the accessToken variable as the bearer token in a call. Below is a simple example.

curl "https://api-school.apple.com/v1/mdmServers" -H "Authorization: Bearer ${accessToken}"

Notice that as part of the setup with didn't run the create_access_token.sh? Thats becuase on the first run of any script, the automation will see that there isn't one and will generate it on the fly for you.

The next part is up to you! How you interact with AxM and the automations and workflow you create is actually the hard part and the part that gets the job done.

If you haven't already seen, here are the [Apple Documents for the ASM Endpoints or ABM Endpoints

Although the scripts take care of keeping the Access Token valid, I didn't actually build in any "self renewal" of the Client Assertion. If this becomes invalid due to being over 180 days old, everything will just exit and error out.

So if you need to renew this, run AxM-API/AutomationScript/create_client_assertion.sh again.

"You took the time to self renew the Access Token so why not the Client Assertion". Great Question! I just didn't, at least not today. Maybe next time I have a few minutes and I don't have a project Im not working on