In this recipe, we will see how to create a workflow that waits for an approver to approve the VM creation before provisioning it. We will learn how to combine mail and external events in a workflow to make it interact with different users.
For this recipe, we first need the provisioning workflow that we have created in the Provisioning a VM from a template recipe. You can use the example workflow, 7.02.1 Provision VM (Base).
Additionally, we need a functional e-mail system as well as a workflow to send e-mails. Refer to the Working with mails recipe in Chapter 4, Working with Plugins. You can use the example workflow, 4.02.1 SendMail as well as its configuration item, 4.2.1 Working with e-mail.
We will also work with events as discussed in the Sending and waiting for custom events recipe in Chapter 3, Visual Programming.