virtinst: Add --transient flag.

If this flag is specified, --import|--boot will create a transient
libvirt domain, ie. one which goes away when the guest shuts down or
the host is rebooted.

(crobinso: some tweaks and tests)

man/virt-install.pod

@@ -1576,6 +1576,15 @@ Show program's version number and exit
 Set the autostart flag for a domain. This causes the domain to be started
 on host boot up.
 
+=item B<--transient>
+
+Use --import or --boot and --transient if you want a transient libvirt
+VM.  These VMs exist only until the domain is shut down or the host
+server is restarted.  Libvirt forgets the XML configuration of the VM
+after either of these events.  Note that the VM's disks will not be
+deleted.  See:
+L<http://wiki.libvirt.org/page/VM_lifecycle#Transient_guest_domains_vs_Persistent_guest_domains>
+
 =item B<--print-xml> [STEP]
 
 Print the generated XML of the guest, instead of defining it. By default this WILL do storage creation (can be disabled with --dry-run). This option implies --quiet.

tests/clitest.py

@@ -797,6 +797,7 @@ c = vinst.add_category("console-tests", "--pxe --nodisks")
 c.add_valid("--nographics")  # mock virsh console waiting
 c.add_valid("--graphics vnc --noreboot")  # mock virt-viewer waiting, with noreboot magic
 c.add_invalid("--noautoconsole --wait 1")  # --wait 1 is converted to 1 second if we are in the test suite, so this should actually touch the wait machinery. however in this case it exits with failure
+c.add_valid("--nographics --transient")  # --transient handling
 
 
 

virt-install

@@ -449,6 +449,9 @@ _cdrom_location_man_page = _("See the man page for examples of "
 
 
 def check_option_collisions(options, guest):
+    if options.noreboot and options.transient:
+        fail(_("--noreboot and --transient can not be specified together"))
+
     # Install collisions
     if sum([bool(l) for l in [options.pxe, options.location,
                       options.cdrom, options.import_install]]) > 1:
@@ -688,13 +691,14 @@ def start_install(guest, options):
         start_time = time.time()
 
         # Do first install phase
-        guest.start_install(meter=meter, doboot=not options.noreboot)
+        guest.start_install(meter=meter, doboot=not options.noreboot,
+                            transient=options.transient)
         cli.connect_console(guest, conscb, wait_on_console)
-        check_domain(guest, conscb,
+        check_domain(guest, conscb, options.transient,
                      wait_on_install, wait_time, start_time)
 
         print_stdout(_("Domain creation completed."))
-        if not guest.domain.isActive():
+        if not options.transient and not guest.domain.isActive():
             if options.noreboot or not guest.installer.has_install_phase():
                 print_stdout(
                     _("You can restart your domain by running:\n  %s") %
@@ -715,21 +719,27 @@ def start_install(guest, options):
         cli.install_fail(guest)
 
 
-def check_domain(guest, conscb, wait_for_install, wait_time, start_time):
+def check_domain(guest, conscb, transient,
+                 wait_for_install, wait_time, start_time):
     """
     Make sure domain ends up in expected state, and wait if for install
     to complete if requested
     """
-    # Wait a bit so info is accurate
     def check_domain_inactive():
-        dominfo = guest.domain.info()
-        state = dominfo[0]
-        logging.debug("Domain state after install: %s", state)
+        try:
+            dominfo = guest.domain.info()
+            state = dominfo[0]
+            logging.debug("Domain state after install: %s", state)
 
-        if state == libvirt.VIR_DOMAIN_CRASHED:
-            fail(_("Domain has crashed."))
+            if state == libvirt.VIR_DOMAIN_CRASHED:
+                fail(_("Domain has crashed."))
 
-        return not guest.domain.isActive()
+            return not guest.domain.isActive()
+        except libvirt.libvirtError, e:
+            if transient and e.get_error_code() == libvirt.VIR_ERR_NO_DOMAIN:
+                logging.debug("transient VM shutdown and disappeared.")
+                return True
+            raise
 
     if check_domain_inactive():
         return
@@ -927,6 +937,9 @@ def parse_args():
     misc.add_argument("--autostart", action="store_true", dest="autostart",
                     default=False,
                     help=_("Have domain autostart on host boot up."))
+    misc.add_argument("--transient", action="store_true", dest="transient",
+                      default=False,
+                      help=_("Create a transient domain."))
     misc.add_argument("--wait", type=int, dest="wait",
                     help=_("Minutes to wait for install to complete."))
 

virtinst/guest.py

@@ -382,7 +382,7 @@ class Guest(XMLBuilder):
 
         return install_xml, final_xml
 
-    def _create_guest(self, meter, install_xml, final_xml, doboot):
+    def _create_guest(self, meter, install_xml, final_xml, doboot, transient):
         """
         Actually do the XML logging, guest defining/creating
 
@@ -392,10 +392,11 @@ class Guest(XMLBuilder):
         meter = util.ensure_meter(meter)
         meter.start(size=None, text=meter_label)
 
-        if doboot or self.installer.has_install_phase():
+        if doboot or transient or self.installer.has_install_phase():
             self.domain = self.conn.createXML(install_xml or final_xml, 0)
 
-        self.domain = self.conn.defineXML(final_xml)
+        if not transient:
+            self.domain = self.conn.defineXML(final_xml)
         meter.end(0)
 
         try:
@@ -428,7 +429,8 @@ class Guest(XMLBuilder):
     ##############
 
     def start_install(self, meter=None,
-                      dry=False, return_xml=False, doboot=True):
+                      dry=False, return_xml=False,
+                      doboot=True, transient=False):
         """
         Begin the guest install (stage1).
         @param return_xml: Don't create the guest, just return generated XML
@@ -455,7 +457,9 @@ class Guest(XMLBuilder):
             self.check_vm_collision(self.conn, self.name,
                                     do_remove=self.replace)
 
-            self._create_guest(meter, install_xml, final_xml, doboot)
+            self._create_guest(meter, install_xml, final_xml,
+                               doboot, transient)
+
             # Set domain autostart flag if requested
             self._flag_autostart()
         finally: