How to get the Azure subscription and resouce group from within a VM using REST API?

Question

A lot of Azure API endpoints require you pass in the subscriptionID and resource group name of the resouce you want to work with.

From a bash script running on an Azure Linux VM, how can I get these info? I can't have the Azure CLI installed hence looking for some REST API.

There is this old answer which I found convoluted and requires the CLI anyway. One answer even mentions this API to get all info of one given VM:

/subscriptions/[subscription-id]/resourceGroups/[resource-group-name]/providers/Microsoft.Compute/virtualMachines/[virtual-machine-name]

It seems to be a chicken and egg problem.

Answer 1

I've found it. The Azure Instance Metadata Service returns a lot of metadata about the Azure VM where the request has made from. I used the following REST endpoint to retrieve the VM's subscriptionId and resourceGroupName:

curl -H Metadata:true "http://169.254.169.254/metadata/instance?api-version=2017-08-01"
{
  "compute": {
    "location": "",
    "name": "",
    "offer": "",
    "osType": "",
    "placementGroupId": "",
    "platformFaultDomain": "",
    "platformUpdateDomain": "",
    "publisher": "",
    "resourceGroupName": "",
    "sku": "",
    "subscriptionId": "",
    "tags": "",
    "version": "",
    "vmId": "",
    "vmScaleSetName": "",
    "vmSize": "",
    "zone": ""
  },
  "network": {
    "interface": [
      {
        "ipv4": {
          "ipAddress": [
            {
              "privateIpAddress": "",
              "publicIpAddress": ""
            }
          ],
          "subnet": [
            {
              "address": "",
              "prefix": ""
            }
          ]
        },
        "ipv6": {
          "ipAddress": []
        },
        "macAddress": ""
      }
    ]
  }
}