Azure REST API’s, versions, and lifecycle

If you want to create your own or to contribute to an existing GitHub project you are on the right page.

Microsoft provides a list of all REST APIs (REST API Browser) available for Azure by clicking on the following link: https://docs.microsoft.com/en-us/rest/api/?view=Azure

For example, if I take the API dedicated to Compute and select Virtual Machines: https://docs.microsoft.com/en-us/rest/api/compute/virtualmachines

I will have access to all the actions I can perform on the Virtual Machines object.

For example, to list all VMs in an Azure subscription: https://docs.microsoft.com/en-us/rest/api/compute/virtualmachines/listall

The major advantage of this site is that it allows live testing of the selected API (by clicking on Try It) from a web browser, without needing to install a third-party tool (such as Postman or others).

All Azure APIs return results in JSON format, making them easily exploitable.

Each Azure API requires passing a mandatory parameter, api-version, to specify the version of the API to use and thus benefit from backward compatibility in case of version changes.

First, install the Az.Resources module:

1Install-Module -Name Az.Resources

In PowerShell, if I want to know the version of the APIs available for a given provider, I need to execute the following command:

1PowerShellGet-AzResourceProvider -ListAvailable | Select-Object ProviderNamespace -ExpandProperty ResourceTypes | select-object ProviderNamespace, RegistrationState, ResourceTypeName,ApiVersions | ft

If I take the Compute provider, I can display the resources with the following command:

1PowerShell(Get-AzResourceProvider -ProviderNamespace Microsoft.Compute).ResourceTypes

And with this command, I can list the available API versions:

1PowerShell((Get-AzResourceProvider -ProviderNamespace Microsoft.Compute).ResourceTypes | Where-Object ResourceTypeName -eq virtualMachines).ApiVersions

So, all those listed are supported. The retention period is quite long, allowing application developers enough time to make necessary modifications without being caught off guard before the API is deprecated.

Each API has its own lifecycle, and there is no official timeline regarding the retention period of older versions.