feat(instances): a running VM can be cloned

libvirt's backup copies the disks of a running or paused VM from one
instant into new volumes while it keeps running; the clone is defined
shut off as before. The VM is held for the copy, the copy can be
cancelled, and recovery reads the job's records and libvirt.

operations/static/operations/job_panel.js

@@ -70,8 +70,9 @@ function jobPanel(element, urls, csrfToken, initialIds) {
 
     function outcomeHtml(job) {
         var left = (job.result && job.result.left_behind) || [];
-        var warn = left.length ? '<div class="small mt-2">Files not removed:</div><ul class="list-unstyled small mb-0">'
-            + left.map(function (path) { return '<li class="text-break"><code>' + esc(path) + "</code></li>"; }).join("") + "</ul>" : "";
+        var note = job.result && job.result.warning ? '<div class="small mt-2">' + esc(job.result.warning) + "</div>" : "";
+        var warn = note + (left.length ? '<div class="small mt-2">Files not removed:</div><ul class="list-unstyled small mb-0">'
+            + left.map(function (path) { return '<li class="text-break"><code>' + esc(path) + "</code></li>"; }).join("") + "</ul>" : "");
         var buttons = '<button type="button" class="btn btn-sm btn-primary" data-refresh="1">Refresh</button>'
             + '<button type="button" class="btn btn-sm btn-outline-secondary" data-dismiss="' + esc(job.id)
             + '">Dismiss</button>';

operations/templates/operations/job.html

@@ -56,6 +56,9 @@
                     </ul>
                 </dd>
             {% endif %}
+            {% if job.result.warning %}
+                <dt class="col-sm-3">{% trans "Warning" %}</dt><dd class="col-sm-9 text-break">{{ job.result.warning }}</dd>
+            {% endif %}
             {% if job.result.links %}
                 <dt class="col-sm-3">{% trans "Results" %}</dt>
                 <dd class="col-sm-9">

operations/tests/js/job_panel.test.js

@@ -92,8 +92,9 @@ assert.strictEqual(window.backgroundJobRunning, true, "still true while the outc
 answer("/j/a", { status: 0 }, false); // a network error: asked again on the next poll
 advance(3000);
 answer("/r", empty);
-answer("/j/a", { ...running, state: "succeeded", result: { left_behind: ["/pool/a.one"] } });
+answer("/j/a", { ...running, state: "succeeded", result: { left_behind: ["/pool/a.one"], warning: "not <thawed>" } });
 assert.ok(el.innerHTML.includes('<li class="text-break"><code>/pool/a.one</code></li>'), "shows the warning from the result");
+assert.ok(el.innerHTML.includes('<div class="small mt-2">not &lt;thawed&gt;</div>'), "shows the result's warning escaped");
 assert.ok(el.innerHTML.includes('class="alert alert-success') && el.innerHTML.includes('<span class="badge bg-success">succeeded</span>')
     && el.innerHTML.includes('<div class="ms-auto d-flex gap-2"><button type="button" class="btn btn-sm btn-primary" data-refresh'),
     "the outcome has the state colour and its buttons on the right");

operations/tests/test_views.py

@@ -73,6 +73,13 @@ class JobsPageTestCase(TransactionTestCase):
         self.assertNotContains(response, "<script>x</script>")
         self.assertContains(response, "Waiting for recovery")
 
+    def test_the_detail_shows_the_results_warning_escaped(self):
+        Operation.objects.filter(pk=self.op.pk).update(result={"warning": "not <b>thawed</b>"},
+                                                       state=Operation.SUCCEEDED)
+        self.client.force_login(self.user)
+        response = self.client.get(reverse("operations:job", args=[self.op.pk]))
+        self.assertContains(response, "not &lt;b&gt;thawed&lt;/b&gt;")
+
     def test_pagination_keeps_the_filters(self):
         for i in range(51):
             Operation.objects.create(kind="test.noop", user=self.user, username="page_user",