Add per-object "restart" option to control restarts.

CHANGELOG.md

@@ -1,6 +1,10 @@
 # Changelog
 
 ## [UNRELEASED]
+
+* Modules:
+    * Improve change detection for domain restarts.
+    * Add per-object "restart" option to control restarts.
 * Lib:
     * XML domain generation:
         * Allow in feature section, customization of the `smbios` option

README.md

@@ -57,6 +57,9 @@ Each set represents a libvirt domain, and has these attributes:
   * `active` (bool or `null`, default `null`)  
   State to put the domain in (running/stopped), or null to ignore.  
 
+  * `restart` (bool or `null`, default `null`)  
+  Whether to restart the domain, or null to restart only if its definition has changed.  
+
   :warning: If this option is specified and not null, any libvirt domain not defined in the list will be deleted.
   Deleting a domain will not delete its volumes, NVRAM, or TPM state.
 
@@ -70,6 +73,9 @@ Each set represents a libvirt network, and has these attributes:
   * `active` (bool or `null`, default `null`)  
   State to put the network in, or null to ignore.  
 
+  * `restart` (bool or `null`, default `null`)  
+  Whether to restart the network, or null to restart only if its definition has changed.  
+
   :warning: If this option is specified and not null, any libvirt network not defined in the list will be deleted.
 
 * `virtualisation.libvirt.connections.<connection>.pools` (list of sets or `null`, default `null`)  
@@ -82,6 +88,9 @@ Each set represents a libvirt storage pool, and has these attributes:
   * `active` (bool or `null`, default `null`)  
   State to put the pool in, or null to ignore.  
 
+  * `restart` (bool or `null`, default `null`)  
+  Whether to restart the pool, or null to restart only if its definition has changed.  
+
   * `volumes` (list of sets, default `[]`)  
   Volumes to create if not already existing.
   Existing volumes not listed will be ignored (not deleted);

modules.nix

@@ -21,6 +21,12 @@ let
                       default = null;
                       description = "state to put the " + singular + " in (or null for ignore)";
                     };
+                  restart = lib.mkOption
+                    {
+                      type = nullOr bool;
+                      default = null;
+                      description = "whether to restart on activation (or null to only restart when changed)";
+                    };
                 };
             }));
           default = null;

tool/nixvirt-module-helper

@@ -13,7 +13,7 @@ with open(args.settingspath,"r") as f:
 class TypeSpec:
     def __init__(self,session,type,itemlist):
         self.oc = nixvirt.getObjectConnection(session,type)
-        self.specList = [nixvirt.ObjectSpec.fromDefinitionFile(self.oc,item["definition"],item.get("active"),item) for item in itemlist]
+        self.specList = [nixvirt.ObjectSpec.fromDefinitionFile(self.oc,item["definition"],item.get("active"),item.get("restart"),item) for item in itemlist]
 
     def deleteOld(self):
         allObjects = self.oc.getAll()

tool/nixvirt.py

@@ -316,7 +316,7 @@ def defineExtra(self,extra):
 # what we want for an object
 class ObjectSpec:
 
-    def __init__(self,oc,specUUID = None,specName = None,specDefXML = None,active = None,extra = None):
+    def __init__(self,oc,specUUID = None,specName = None,specDefXML = None,active = None,restart = None,extra = None):
         if specUUID is not None:
             self.subject = oc.fromUUIDOrNone(specUUID)
         elif specName is not None:
@@ -335,28 +335,29 @@ def __init__(self,oc,specUUID = None,specName = None,specDefXML = None,active =
         self.specUUID = specUUID
         self.active = active
         self.extra = extra
+        self.restart = restart
 
     def vreport(self,msg):
         self.oc.vreport(self.specUUID,msg)
 
-    def fromUUID(oc,specUUID,active):
-        return ObjectSpec(oc,specUUID = specUUID,active = active)
+    def fromUUID(oc,specUUID,active,restart):
+        return ObjectSpec(oc,specUUID = specUUID,active = active,restart = restart)
 
-    def fromName(oc,specName,active):
-        return ObjectSpec(oc,specName = specName,active = active)
+    def fromName(oc,specName,active,restart):
+        return ObjectSpec(oc,specName = specName,active = active,restart = restart)
 
-    def fromDefinition(oc,specDefXML,active,extra = None):
+    def fromDefinition(oc,specDefXML,active,restart,extra = None):
         specDefETree = xmlToETree(specDefXML)
         specUUID = uuid.UUID(specDefETree.find("uuid").text).bytes
         specName = specDefETree.find("name").text
         fixedDefETree = oc._fixDefinitionETree(specUUID,specDefETree)
         if fixedDefETree is not None:
             specDefXML = eTreeToXML(fixedDefETree)
-        return ObjectSpec(oc,specUUID = specUUID,specName = specName,specDefXML = specDefXML,active = active, extra = extra)
+        return ObjectSpec(oc,specUUID = specUUID,specName = specName,specDefXML = specDefXML,active = active,restart = restart, extra = extra)
 
-    def fromDefinitionFile(oc,path,active,extra = None):
+    def fromDefinitionFile(oc,path,active,restart,extra = None):
         specDefXML = oc.getFile(path)
-        return ObjectSpec.fromDefinition(oc,specDefXML,active, extra = extra)
+        return ObjectSpec.fromDefinition(oc,specDefXML,active,restart, extra = extra)
 
     def define(self):
         if self.specDefXML is not None:
@@ -368,16 +369,24 @@ def define(self):
                 self.oc._cleanDefETree(self.specDefXML,oldDefETree)
                 self.vreport("redefine")
                 newvobject = self.oc._fromXML(self.specDefXML)
-                newDefETree = newvobject.descriptionETree()
-                self.oc._cleanDefETree(self.specDefXML,newDefETree)
-                diff = xmldiff.main.diff_trees(oldDefETree,newDefETree)
-                if len(diff) > 0:
-                    if self.oc.session.verbose:
-                        difftext = xmldiff.main.diff_trees(oldDefETree,newDefETree,formatter=xmldiff.formatting.DiffFormatter())
-                        self.vreport("changed:\n" + difftext)
-                    self.subject._deactivate()
-                else:
-                    self.vreport("unchanged")
+                match self.restart:
+                    case True:
+                        self.vreport("always restart")
+                        self.subject._deactivate()
+                    case False:
+                        self.vreport("never restart")
+                    case None:
+                        self.vreport("detect restart")
+                        newDefETree = newvobject.descriptionETree()
+                        self.oc._cleanDefETree(self.specDefXML,newDefETree)
+                        diff = xmldiff.main.diff_trees(oldDefETree,newDefETree)
+                        if len(diff) > 0:
+                            if self.oc.session.verbose:
+                                difftext = xmldiff.main.diff_trees(oldDefETree,newDefETree,formatter=xmldiff.formatting.DiffFormatter())
+                                self.vreport("changed:\n" + difftext)
+                            self.subject._deactivate()
+                        else:
+                            self.vreport("unchanged")
                 self.subject = newvobject
             else:
                 self.vreport("define new")

tool/virtdeclare

@@ -11,6 +11,7 @@ specgroup.add_argument('--define', action='store', metavar='PATH', help='XML obj
 specgroup.add_argument('--uuid', action='store', metavar='ID', help='object UUID')
 specgroup.add_argument('--name', action='store', metavar='ID', help='object name')
 parser.add_argument('--state', action='store', choices = ['active','inactive'], help='state to put object in')
+parser.add_argument('--restart', action='store', choices = ['always','never','ifchanged'], help='whether to restart the object')
 parser.add_argument('--auto', action='store_true', help='set autostart to match state')
 args = parser.parse_args()
 
@@ -23,18 +24,28 @@ match args.state:
     case None:
         active = None
 
+match args.restart:
+    case "always":
+        restart = True
+    case "never":
+        restart = False
+    case "ifchanged":
+        restart = None
+    case None:
+        restart = None
+
 try:
     session = nixvirt.Session(args.connect,args.verbose)
     oc = nixvirt.getObjectConnection(session,args.type)
 
     # fetch object
     if args.define:
-        spec = nixvirt.ObjectSpec.fromDefinitionFile(oc,args.define,active)
+        spec = nixvirt.ObjectSpec.fromDefinitionFile(oc,args.define,active,restart)
     elif args.uuid:
         specUUID = uuid.UUID(args.uuid).bytes
-        spec = nixvirt.ObjectSpec.fromUUID(oc,specUUID,active)
+        spec = nixvirt.ObjectSpec.fromUUID(oc,specUUID,active,restart)
     else:
-        spec = nixvirt.ObjectSpec.fromName(oc,args.name,active)
+        spec = nixvirt.ObjectSpec.fromName(oc,args.name,active,restart)
 
     # define object
     spec.define()