Moving Subscriptions with Azure Rest API

Question

I've been trying to move subscriptions under one management group to other management groups using Azure REST API and, according to documentation it seems possible using PATCH on this endpoint:

https://management.azure.com/providers/Microsoft.Management/managementGroups/{groupId}?api-version=2020-05-01

with a corresponding JSON body:

{
"properties":{
"tenantId": "${tenantId}",
"displayName": "${displayName}",
"name": "/providers/Microsoft.Management/managementGroups/${displayName}",
"children": [
{
"type": "/subscriptions",
"displayName": "${displayName}",
"id": "/subscriptions/${subscriptionId}",
"name": "${subscriptionId}"
}
]
}
}

service principal has these custom 'action' permissions:

                "Microsoft.Management/managementGroups/write",
                "Microsoft.Management/managementGroups/subscriptions/write",
                "Microsoft.Authorization/roleAssignments/write",
                "Microsoft.Authorization/roleAssignments/delete",
                "Microsoft.Management/register/action",
                "Microsoft.Management/managementGroups/read",
                "Microsoft.Management/managementGroups/subscriptions/read"

Posting the above JSON body, with supplied bearer token to the above endpoint returns responses '200 OK.' Yet, no actions are taken in the portal, and the subscription remains in the original management group.

Is there anything that I'm doing incorrectly here / should check?

Answer 1

FYI, the issue was because I was using the incorrect API. Should have been using this https://learn.microsoft.com/en-us/rest/api/managementgroups/management-group-subscriptions/create for actually moving an existing subscription to another management group.

All search results kept returning https://learn.microsoft.com/en-us/rest/api/managementgroups/management-groups, and it seems that moving / updating management groups to include new 'child' subscriptions would be possible using this API...but apparently it's not. Would be helpful if that was documented more clearly to save other users time.