commit e69d05fdff4cab460a92a482de58e00523d44c58
Author: Iustin Pop <iustin@google.com>
Date:   Wed Oct 8 10:36:29 2008 +0000

    Move the hypervisor attribute to the instances
    
    This (big) patch moves the hypervisor type from the cluster to the
    instance level; the cluster attribute remains as the default hypervisor,
    and will be renamed accordingly in a next patch. The cluster also gains
    the ‘enable_hypervisors’ attribute, and instances can be created with
    any of the enabled ones (no provision yet for changing that attribute).
    
    The many many changes in the rpc/backend layer are due to the fact that
    all backend code read the hypervisor from the local copy of the config,
    and now we have to send it (either in the instance object, or as a
    separate parameter) for each function.
    
    The node list by default will list the node free/total memory for the
    default hypervisor, a new flag to it should exist to select another
    hypervisor. Instance list has a new field, hypervisor, that shows the
    instance hypervisor. Cluster verify runs for all enabled hypervisor
    types.
    
    The new FIXMEs are related to IAllocator, since now the node
    total/free/used memory counts are wrong (we can't reliably compute the
    free memory).
    
    Reviewed-by: imsnah

diff --git a/lib/backend.py b/lib/backend.py
index 5e11fcb..0df7a00 100644
--- a/lib/backend.py
+++ b/lib/backend.py
@@ -231,18 +231,21 @@ def LeaveCluster():
   raise errors.QuitGanetiException(False, 'Shutdown scheduled')
 
 
-def GetNodeInfo(vgname):
+def GetNodeInfo(vgname, hypervisor_type):
   """Gives back a hash with different informations about the node.
 
-  Returns:
-    { 'vg_size' : xxx,  'vg_free' : xxx, 'memory_domain0': xxx,
-      'memory_free' : xxx, 'memory_total' : xxx }
-    where
-    vg_size is the size of the configured volume group in MiB
-    vg_free is the free size of the volume group in MiB
-    memory_dom0 is the memory allocated for domain0 in MiB
-    memory_free is the currently available (free) ram in MiB
-    memory_total is the total number of ram in MiB
+  @type vgname: C{string}
+  @param vgname: the name of the volume group to ask for disk space information
+  @type hypervisor_type: C{str}
+  @param hypervisor_type: the name of the hypervisor to ask for
+      memory information
+  @rtype: C{dict}
+  @return: dictionary with the following keys:
+      - vg_size is the size of the configured volume group in MiB
+      - vg_free is the free size of the volume group in MiB
+      - memory_dom0 is the memory allocated for domain0 in MiB
+      - memory_free is the currently available (free) ram in MiB
+      - memory_total is the total number of ram in MiB
 
   """
   outputarray = {}
@@ -250,7 +253,7 @@ def GetNodeInfo(vgname):
   outputarray['vg_size'] = vginfo['vg_size']
   outputarray['vg_free'] = vginfo['vg_free']
 
-  hyper = hypervisor.GetHypervisor(_GetConfig())
+  hyper = hypervisor.GetHypervisor(hypervisor_type)
   hyp_info = hyper.GetNodeInfo()
   if hyp_info is not None:
     outputarray.update(hyp_info)
@@ -267,25 +270,36 @@ def GetNodeInfo(vgname):
 def VerifyNode(what, cluster_name):
   """Verify the status of the local node.
 
-  Args:
-    what - a dictionary of things to check:
-      'filelist' : list of files for which to compute checksums
-      'nodelist' : list of nodes we should check communication with
-      'hypervisor': run the hypervisor-specific verify
+  Based on the input L{what} parameter, various checks are done on the
+  local node.
+
+  If the I{filelist} key is present, this list of
+  files is checksummed and the file/checksum pairs are returned.
+
+  If the I{nodelist} key is present, we check that we have
+  connectivity via ssh with the target nodes (and check the hostname
+  report).
 
-  Requested files on local node are checksummed and the result returned.
+  If the I{node-net-test} key is present, we check that we have
+  connectivity to the given nodes via both primary IP and, if
+  applicable, secondary IPs.
+
+  @type what: C{dict}
+  @param what: a dictionary of things to check:
+      - filelist: list of files for which to compute checksums
+      - nodelist: list of nodes we should check ssh communication with
+      - node-net-test: list of nodes we should check node daemon port
+        connectivity with
+      - hypervisor: list with hypervisors to run the verify for
 
-  The nodelist is traversed, with the following checks being made
-  for each node:
-  - known_hosts key correct
-  - correct resolving of node name (target node returns its own hostname
-    by ssh-execution of 'hostname', result compared against name in list.
 
   """
   result = {}
 
   if 'hypervisor' in what:
-    result['hypervisor'] = hypervisor.GetHypervisor(_GetConfig()).Verify()
+    result['hypervisor'] = my_dict = {}
+    for hv_name in what['hypervisor']:
+      my_dict[hv_name] = hypervisor.GetHypervisor(hv_name).Verify()
 
   if 'filelist' in what:
     result['filelist'] = utils.FingerprintFiles(what['filelist'])
@@ -415,41 +429,49 @@ def BridgesExist(bridges_list):
   return True
 
 
-def GetInstanceList():
+def GetInstanceList(hypervisor_list):
   """Provides a list of instances.
 
-  Returns:
-    A list of all running instances on the current node
-    - instance1.example.com
-    - instance2.example.com
+  @type hypervisor_list: list
+  @param hypervisor_list: the list of hypervisors to query information
+
+  @rtype: list
+  @return: a list of all running instances on the current node
+             - instance1.example.com
+             - instance2.example.com
 
   """
-  try:
-    names = hypervisor.GetHypervisor(_GetConfig()).ListInstances()
-  except errors.HypervisorError, err:
-    logging.exception("Error enumerating instances")
-    raise
+  results = []
+  for hname in hypervisor_list:
+    try:
+      names = hypervisor.GetHypervisor(hname).ListInstances()
+      results.extend(names)
+    except errors.HypervisorError, err:
+      logging.exception("Error enumerating instances for hypevisor %s", hname)
+      # FIXME: should we somehow not propagate this to the master?
+      raise
 
-  return names
+  return results
 
 
-def GetInstanceInfo(instance):
+def GetInstanceInfo(instance, hname):
   """Gives back the informations about an instance as a dictionary.
 
-  Args:
-    instance: name of the instance (ex. instance1.example.com)
+  @type instance: string
+  @param instance: the instance name
+  @type hname: string
+  @param hname: the hypervisor type of the instance
 
-  Returns:
-    { 'memory' : 511, 'state' : '-b---', 'time' : 3188.8, }
-    where
-    memory: memory size of instance (int)
-    state: xen state of instance (string)
-    time: cpu time of instance (float)
+  @rtype: dict
+  @return: dictionary with the following keys:
+      - memory: memory size of instance (int)
+      - state: xen state of instance (string)
+      - time: cpu time of instance (float)
 
   """
   output = {}
 
-  iinfo = hypervisor.GetHypervisor(_GetConfig()).GetInstanceInfo(instance)
+  iinfo = hypervisor.GetHypervisor(hname).GetInstanceInfo(instance)
   if iinfo is not None:
     output['memory'] = iinfo[2]
     output['state'] = iinfo[4]
@@ -458,34 +480,38 @@ def GetInstanceInfo(instance):
   return output
 
 
-def GetAllInstancesInfo():
+def GetAllInstancesInfo(hypervisor_list):
   """Gather data about all instances.
 
   This is the equivalent of `GetInstanceInfo()`, except that it
   computes data for all instances at once, thus being faster if one
   needs data about more than one instance.
 
-  Returns: a dictionary of dictionaries, keys being the instance name,
-    and with values:
-    { 'memory' : 511, 'state' : '-b---', 'time' : 3188.8, }
-    where
-    memory: memory size of instance (int)
-    state: xen state of instance (string)
-    time: cpu time of instance (float)
-    vcpus: the number of cpus
+  @type hypervisor_list: list
+  @param hypervisor_list: list of hypervisors to query for instance data
+
+  @rtype: dict of dicts
+  @return: dictionary of instance: data, with data having the following keys:
+      - memory: memory size of instance (int)
+      - state: xen state of instance (string)
+      - time: cpu time of instance (float)
+      - vcpuus: the number of vcpus
 
   """
   output = {}
 
-  iinfo = hypervisor.GetHypervisor(_GetConfig()).GetAllInstancesInfo()
-  if iinfo:
-    for name, inst_id, memory, vcpus, state, times in iinfo:
-      output[name] = {
-        'memory': memory,
-        'vcpus': vcpus,
-        'state': state,
-        'time': times,
-        }
+  for hname in hypervisor_list:
+    iinfo = hypervisor.GetHypervisor(hname).GetAllInstancesInfo()
+    if iinfo:
+      for name, inst_id, memory, vcpus, state, times in iinfo:
+        if name in output:
+          raise errors.HypervisorError("Instance %s running duplicate" % name)
+        output[name] = {
+          'memory': memory,
+          'vcpus': vcpus,
+          'state': state,
+          'time': times,
+          }
 
   return output
 
@@ -499,7 +525,6 @@ def AddOSToInstance(instance, os_disk, swap_disk):
     swap_disk: the instance-visible name of the swap device
 
   """
-  cfg = _GetConfig()
   inst_os = OSFromDisk(instance.os)
 
   create_script = inst_os.create_script
@@ -535,7 +560,7 @@ def AddOSToInstance(instance, os_disk, swap_disk):
                                 inst_os.path, create_script, instance.name,
                                 real_os_dev.dev_path, real_swap_dev.dev_path,
                                 logfile)
-  env = {'HYPERVISOR': cfg.GetHypervisorType()}
+  env = {'HYPERVISOR': instance.hypervisor}
 
   result = utils.RunCmd(command, env=env)
   if result.failed:
@@ -666,17 +691,19 @@ def _GatherBlockDevs(instance):
 def StartInstance(instance, extra_args):
   """Start an instance.
 
-  Args:
-    instance - name of instance to start.
+  @type instance: instance object
+  @param instance: the instance object
+  @rtype: boolean
+  @return: whether the startup was successful or not
 
   """
-  running_instances = GetInstanceList()
+  running_instances = GetInstanceList([instance.hypervisor])
 
   if instance.name in running_instances:
     return True
 
   block_devices = _GatherBlockDevs(instance)
-  hyper = hypervisor.GetHypervisor(_GetConfig())
+  hyper = hypervisor.GetHypervisor(instance.hypervisor)
 
   try:
     hyper.StartInstance(instance, block_devices, extra_args)
@@ -690,16 +717,19 @@ def StartInstance(instance, extra_args):
 def ShutdownInstance(instance):
   """Shut an instance down.
 
-  Args:
-    instance - name of instance to shutdown.
+  @type instance: instance object
+  @param instance: the instance object
+  @rtype: boolean
+  @return: whether the startup was successful or not
 
   """
-  running_instances = GetInstanceList()
+  hv_name = instance.hypervisor
+  running_instances = GetInstanceList([hv_name])
 
   if instance.name not in running_instances:
     return True
 
-  hyper = hypervisor.GetHypervisor(_GetConfig())
+  hyper = hypervisor.GetHypervisor(hv_name)
   try:
     hyper.StopInstance(instance)
   except errors.HypervisorError, err:
@@ -711,7 +741,7 @@ def ShutdownInstance(instance):
 
   time.sleep(1)
   for dummy in range(11):
-    if instance.name not in GetInstanceList():
+    if instance.name not in GetInstanceList([hv_name]):
       break
     time.sleep(10)
   else:
@@ -725,7 +755,7 @@ def ShutdownInstance(instance):
       return False
 
     time.sleep(1)
-    if instance.name in GetInstanceList():
+    if instance.name in GetInstanceList([hv_name]):
       logging.error("could not shutdown instance '%s' even by destroy",
                     instance.name)
       return False
@@ -741,13 +771,13 @@ def RebootInstance(instance, reboot_type, extra_args):
     reboot_type - how to reboot [soft,hard,full]
 
   """
-  running_instances = GetInstanceList()
+  running_instances = GetInstanceList([instance.hypervisor])
 
   if instance.name not in running_instances:
     logging.error("Cannot reboot instance that is not running")
     return False
 
-  hyper = hypervisor.GetHypervisor(_GetConfig())
+  hyper = hypervisor.GetHypervisor(instance.hypervisor)
   if reboot_type == constants.INSTANCE_REBOOT_SOFT:
     try:
       hyper.RebootInstance(instance)
@@ -764,7 +794,6 @@ def RebootInstance(instance, reboot_type, extra_args):
   else:
     raise errors.ParameterError("reboot_type invalid")
 
-
   return True
 
 
@@ -784,7 +813,7 @@ def MigrateInstance(instance, target, live):
       - msg is a string with details in case of failure
 
   """
-  hyper = hypervisor.GetHypervisor(_GetConfig())
+  hyper = hypervisor.GetHypervisor(instance.hypervisor_name)
 
   try:
     hyper.MigrateInstance(instance.name, target, live)
@@ -1464,7 +1493,6 @@ def ImportOSIntoInstance(instance, os_disk, swap_disk, src_node, src_image,
     False in case of error, True otherwise.
 
   """
-  cfg = _GetConfig()
   inst_os = OSFromDisk(instance.os)
   import_script = inst_os.import_script
 
@@ -1507,7 +1535,7 @@ def ImportOSIntoInstance(instance, os_disk, swap_disk, src_node, src_image,
                                logfile)
 
   command = '|'.join([utils.ShellQuoteArgs(remotecmd), comprcmd, impcmd])
-  env = {'HYPERVISOR': cfg.GetHypervisorType()}
+  env = {'HYPERVISOR': instance.hypervisor}
 
   result = utils.RunCmd(command, env=env)
 
