add UUID options

README.md

@@ -16,6 +16,10 @@ Role Variables
   VM console logs, if a VM-specific log file path is not given. Default is
   "/var/log/libvirt/qemu/".
 
+- `libvirt_vm_default_uuid_deterministic`: Whether UUID should be calculated by
+  hashing the VM name. If not, the UUID is randomly generated by libvirt when
+  the VM is defined. Default is False.
+
 - `libvirt_vm_image_cache_path`: The directory in which to cache downloaded
   images. Default is "/tmp/".
 
@@ -64,6 +68,12 @@ Role Variables
 
     - `name`: the name to assign to the VM.
 
+    - `uuid`: the UUID to manually assign to the VM. If specified, neither
+      `uuid_deterministic` nor `libvirt_vm_default_uuid_deterministic` are used.
+
+    - `uuid_deterministic`: overrides default set in
+      `libvirt_vm_default_uuid_deterministic`
+
     - `memory_mb`: the memory to assign to the VM, in megabytes.
 
     - `vcpus`: the number of VCPU cores to assign to the VM.

defaults/main.yml

@@ -4,6 +4,10 @@
 # file path is not given.
 libvirt_vm_default_console_log_dir: "/var/log/libvirt-consoles/"
 
+# Whether UUID should be calculated by hashing the VM name. If not, the UUID is
+# randomly generated by libvirt when the VM is defined.
+libvirt_vm_default_uuid_deterministic: False
+
 # The default location for libvirt images
 libvirt_volume_default_images_path: '/var/lib/libvirt/images'
 

templates/vm.xml.j2

@@ -1,5 +1,10 @@
 <domain type='{{ libvirt_vm_engine }}'>
   <name>{{ vm.name }}</name>
+  {% if vm.uuid is defined %}
+  <uuid>{{ vm.uuid }}</uuid>
+  {% elif (libvirt_vm_default_uuid_deterministic | bool) or (vm.uuid_deterministic is defined and (vm.uuid_deterministic | bool)) %}
+  <uuid>{{ vm.name | to_uuid }}</uuid>
+  {% endif %}
   <memory>{{ vm.memory_mb | int * 1024 }}</memory>
   <vcpu>{{ vm.vcpus }}</vcpu>
   {% if vm.clock_offset |default( libvirt_vm_clock_offset ) %}