generatename: Move libvirt collision handling to callers

Make every caller pass an explicit cb that handles libvirt
collision processing. Makes it easier to see exactly what is going
on at the call impls

virtManager/create.py

@@ -1494,8 +1494,10 @@ class vmmCreate(vmmGObjectUI):
             basename += "-%s" % _pretty_arch(self._guest.os.arch)
             force_num = False
 
-        return virtinst.generatename.generate_name(basename,
-            self.conn.get_backend().lookupByName,
+        def cb(n):
+            return virtinst.generatename.check_libvirt_collision(
+                self.conn.get_backend().lookupByName, n)
+        return virtinst.generatename.generate_name(basename, cb,
             start_num=force_num and 1 or 2, force_num=force_num,
             sep=not force_num and "-" or "")
 

virtManager/createnet.py

@@ -114,8 +114,10 @@ class vmmCreateNetwork(vmmGObjectUI):
 
     def reset_state(self):
         basename = "network"
-        default_name = generatename.generate_name(
-                basename, self.conn.get_backend().networkLookupByName)
+        def cb(n):
+            return generatename.check_libvirt_collision(
+                self.conn.get_backend().networkLookupByName, n)
+        default_name = generatename.generate_name(basename, cb)
         self.widget("net-name").set_text(default_name)
 
         self.widget("net-dns-use-netname").set_active(True)

virtManager/snapshots.py

@@ -118,7 +118,9 @@ class vmmSnapshotNew(vmmGObjectUI):
 
     def _reset_state(self):
         basename = "snapshot"
-        cb = self.vm.get_backend().snapshotLookupByName
+        def cb(n):
+            return generatename.check_libvirt_collision(
+                self.vm.get_backend().snapshotLookupByName, n)
         default_name = generatename.generate_name(
                 basename, cb, sep="", start_num=1, force_num=True)
 

virtinst/cloner.py

@@ -493,11 +493,9 @@ class Cloner(object):
             clonebase = newname
 
         clonebase = os.path.join(dirname, clonebase)
-        return generatename.generate_name(
-                    clonebase,
-                    lambda p: DeviceDisk.path_definitely_exists(self.conn, p),
-                    suffix,
-                    lib_collision=False)
+        def cb(p):
+            return DeviceDisk.path_definitely_exists(self.conn, p)
+        return generatename.generate_name(clonebase, cb, suffix=suffix)
 
     def generate_clone_name(self):
         # If the orig name is "foo-clone", we don't want the clone to be
@@ -512,9 +510,11 @@ class Cloner(object):
                 start_num = int(str(num_match.group()))
             basename = basename.replace(match.group(), "")
 
+        def cb(n):
+            return generatename.check_libvirt_collision(
+                self.conn.lookupByName, n)
         basename = basename + "-clone"
-        return generatename.generate_name(basename,
-                                  self.conn.lookupByName,
+        return generatename.generate_name(basename, cb,
                                   sep="", start_num=start_num)
 
 

virtinst/generatename.py

@@ -8,7 +8,7 @@
 import libvirt
 
 
-def libvirt_collision(collision_cb, val):
+def check_libvirt_collision(collision_cb, val):
     """
     Run the passed collision function with val as the only argument:
     If libvirtError is raised, return False
@@ -24,7 +24,7 @@ def libvirt_collision(collision_cb, val):
     return check
 
 
-def generate_name(base, collision_cb, suffix="", lib_collision=True,
+def generate_name(base, collision_cb, suffix="",
                   start_num=1, sep="-", force_num=False):
     """
     Generate a new name from the passed base string, verifying it doesn't
@@ -42,8 +42,6 @@ def generate_name(base, collision_cb, suffix="", lib_collision=True,
     :param base: The base string to use for the name (e.g. "my-orig-vm-clone")
     :param collision_cb: A callback function to check for collision,
         receives the generated name as its only arg
-    :param lib_collision: If true, the collision_cb is not a boolean function,
-        and instead throws a libvirt error on failure
     :param start_num: The number to start at for generating non colliding names
     :param sep: The separator to use between the basename and the
         generated number (default is "-")
@@ -51,12 +49,6 @@ def generate_name(base, collision_cb, suffix="", lib_collision=True,
     """
     base = str(base)
 
-    def collide(n):
-        if lib_collision:
-            return libvirt_collision(collision_cb, n)
-        else:
-            return collision_cb(n)
-
     numrange = list(range(start_num, start_num + 100000))
     if not force_num:
         numrange = [None] + numrange
@@ -68,7 +60,7 @@ def generate_name(base, collision_cb, suffix="", lib_collision=True,
             tryname += ("%s%d" % (sep, i))
         tryname += suffix
 
-        if not collide(tryname):
+        if not collision_cb(tryname):
             ret = tryname
             break
 

virtinst/guest.py

@@ -131,7 +131,8 @@ class Guest(XMLBuilder):
 
         for ignore in range(256):
             uuid = _randomUUID()
-            if not generatename.libvirt_collision(conn.lookupByUUID, uuid):
+            if not generatename.check_libvirt_collision(
+                    conn.lookupByUUID, uuid):
                 return uuid
 
         logging.error("Failed to generate non-conflicting UUID")

virtinst/storage.py

@@ -248,8 +248,6 @@ class StoragePool(_StorageObject):
                 if pool.name == name:
                     return True
             return False
-
-        kwargs["lib_collision"] = False
         return generatename.generate_name(basename, cb, **kwargs)
 
     @staticmethod
@@ -560,7 +558,8 @@ class StorageVolume(_StorageObject):
         def cb(tryname):
             if tryname in collidelist:
                 return True
-            return pool_object.storageVolLookupByName(tryname)
+            return generatename.check_libvirt_collision(
+                pool_object.storageVolLookupByName, tryname)
 
         StoragePool.ensure_pool_is_running(pool_object, refresh=True)
         return generatename.generate_name(basename, cb, **kwargs)