Use a UUID instead of a named identity for httpboot

This is an alternative to https://review.opendev.org/c/openstack/sushy-tools/+/902015
The tl;dr is we can leak the uuid out in some weird cases and
while things will just keep working, some methods internally
really just want a UUID and not a name. The other patch
is the name fix.

This, explicitly uses a UUID for httpboot, in the event
it is still happilly working with a name up until that point.

Change-Id: I52121f7e6148aaa3739bc9900b4480b7b3dff8fc

sushy_tools/emulator/main.py

@@ -369,6 +369,7 @@ def system_collection_resource():
 @api_utils.ensure_instance_access
 @api_utils.returns_json
 def system_resource(identity):
+    uuid = app.systems.uuid(identity)
     if flask.request.method == 'GET':
 
         app.logger.debug('Serving resources for system "%s"', identity)
@@ -422,7 +423,7 @@ def system_resource(identity):
                 try:
                     # Mount it as an ISO
                     app.systems.set_boot_image(
-                        identity,
+                        uuid,
                         'Cd', boot_image=image_path,
                         write_protected=True)
                     # Set it for our emulator's API surface to return it
@@ -468,7 +469,7 @@ def system_resource(identity):
 
         if indicator_led_state:
             app.indicators.set_indicator_state(
-                app.systems.uuid(identity), indicator_led_state)
+                uuid, indicator_led_state)
 
             app.logger.info('Set indicator LED to "%s" for system "%s"',
                             indicator_led_state, identity)

sushy_tools/tests/unit/emulator/test_main.py

@@ -292,7 +292,7 @@ class SystemsTestCase(EmulatorTestCase):
         set_http_boot_uri = systems_mock.return_value.set_http_boot_uri
         set_boot_device.assert_called_once_with('xxxx-yyyy-zzzz', 'Cd')
         set_boot_image.assert_called_once_with(
-            'xxxx-yyyy-zzzz',
+            mock.ANY,
             'Cd',
             boot_image='/path/to/file.iso',
             write_protected=True)