Add utils.IsNormAbsPath function

[ganeti-local] / lib / hypervisor / hv_base.py

diff --git a/lib/hypervisor/hv_base.py b/lib/hypervisor/hv_base.py
index ebae830..442cd81 100644 (file)
--- a/lib/hypervisor/hv_base.py
+++ b/lib/hypervisor/hv_base.py
@@ -21,9 +21,65 @@
 
 """Base class for all hypervisors
 
 
 """Base class for all hypervisors
 

+The syntax for the _CHECK variables and the contents of the PARAMETERS
+dict is the same, see the docstring for L{BaseHypervisor.PARAMETERS}.
+
+@var _FILE_CHECK: stub for file checks, without the required flag
+@var _DIR_CHECK: stub for directory checks, without the required flag
+@var REQ_FILE_CHECK: mandatory file parameter
+@var OPT_FILE_CHECK: optional file parameter
+@var REQ_DIR_CHECK: mandatory directory parametr
+@var OPT_DIR_CHECK: optional directory parameter
+@var NO_CHECK: parameter without any checks at all
+@var REQUIRED_CHECK: parameter required to exist (and non-false), but
+    without other checks; beware that this can't be used for boolean
+    parameters, where you should use NO_CHECK or a custom checker
+

 """
 
 """
 

+import os
+import re
+
+

 from ganeti import errors
 from ganeti import errors

+from ganeti import utils
+
+
+# Read the BaseHypervisor.PARAMETERS docstring for the syntax of the
+# _CHECK values
+
+# must be afile
+_FILE_CHECK = (os.path.isabs, "must be an absolute path",
+              os.path.isfile, "not found or not a file")
+
+# must be a directory
+_DIR_CHECK = (os.path.isabs, "must be an absolute path",
+             os.path.isdir, "not found or not a directory")
+
+# nice wrappers for users
+REQ_FILE_CHECK = (True, ) + _FILE_CHECK
+OPT_FILE_CHECK = (False, ) + _FILE_CHECK
+REQ_DIR_CHECK = (True, ) + _DIR_CHECK
+OPT_DIR_CHECK = (False, ) + _DIR_CHECK
+
+# no checks at all
+NO_CHECK = (False, None, None, None, None)
+
+# required, but no other checks
+REQUIRED_CHECK = (True, None, None, None, None)
+
+def ParamInSet(required, my_set):
+  """Builds parameter checker for set membership.
+
+  @type required: boolean
+  @param required: whether this is a required parameter
+  @type my_set: tuple, list or set
+  @param my_set: allowed values set
+
+  """
+  fn = lambda x: x in my_set
+  err = ("The value must be one of: %s" % utils.CommaJoin(my_set))
+  return (required, fn, err, None, None)

 
 
 class BaseHypervisor(object):
 
 
 class BaseHypervisor(object):

@@ -32,13 +88,24 @@ class BaseHypervisor(object):
   The goal is that all aspects of the virtualisation technology are
   abstracted away from the rest of code.
 
   The goal is that all aspects of the virtualisation technology are
   abstracted away from the rest of code.
 

+  @cvar PARAMETERS: a dict of parameter name: check type; the check type is
+      a five-tuple containing:
+          - the required flag (boolean)
+          - a function to check for syntax, that will be used in
+            L{CheckParameterSyntax}, in the master daemon process
+          - an error message for the above function
+          - a function to check for parameter validity on the remote node,
+            in the L{ValidateParameters} function
+          - an error message for the above function
+

   """
   """

-  PARAMETERS = []
+  PARAMETERS = {}
+  ANCILLARY_FILES = []

 
   def __init__(self):
     pass
 
 
   def __init__(self):
     pass
 

-  def StartInstance(self, instance, block_devices, extra_args):
+  def StartInstance(self, instance, block_devices):

     """Start an instance."""
     raise NotImplementedError
 
     """Start an instance."""
     raise NotImplementedError
 

@@ -84,13 +151,26 @@ class BaseHypervisor(object):
     """
     raise NotImplementedError
 
     """
     raise NotImplementedError
 

-  @staticmethod
-  def GetShellCommandForConsole(instance):
+  @classmethod
+  def GetShellCommandForConsole(cls, instance, hvparams, beparams):

     """Return a command for connecting to the console of an instance.
 
     """
     raise NotImplementedError
 
     """Return a command for connecting to the console of an instance.
 
     """
     raise NotImplementedError
 

+  @classmethod
+  def GetAncillaryFiles(cls):
+    """Return a list of ancillary files to be copied to all nodes as ancillary
+    configuration files.
+
+    @rtype: list of strings
+    @return: list of absolute paths of files to ship cluster-wide
+
+    """
+    # By default we return a member variable, so that if an hypervisor has just
+    # a static list of files it doesn't have to override this function.
+    return cls.ANCILLARY_FILES
+

   def Verify(self):
     """Verify the hypervisor.
 
   def Verify(self):
     """Verify the hypervisor.
 

@@ -168,14 +248,25 @@ class BaseHypervisor(object):
     """
     for key in hvparams:
       if key not in cls.PARAMETERS:
     """
     for key in hvparams:
       if key not in cls.PARAMETERS:

-        raise errors.HypervisorError("Hypervisor parameter '%s'"
-                                     " not supported" % key)
-    for key in cls.PARAMETERS:
-      if key not in hvparams:
-        raise errors.HypervisorError("Hypervisor parameter '%s'"
-                                     " missing" % key)
-
-  def ValidateParameters(self, hvparams):
+        raise errors.HypervisorError("Parameter '%s' is not supported" % key)
+
+    # cheap tests that run on the master, should not access the world
+    for name, (required, check_fn, errstr, _, _) in cls.PARAMETERS.items():
+      if name not in hvparams:
+        raise errors.HypervisorError("Parameter '%s' is missing" % name)
+      value = hvparams[name]
+      if not required and not value:
+        continue
+      if not value:
+        raise errors.HypervisorError("Parameter '%s' is required but"
+                                     " is currently not defined" % (name, ))
+      if check_fn is not None and not check_fn(value):
+        raise errors.HypervisorError("Parameter '%s' fails syntax"
+                                     " check: %s (current value: '%s')" %
+                                     (name, errstr, value))
+
+  @classmethod
+  def ValidateParameters(cls, hvparams):

     """Check the given parameters for validity.
 
     This should check the passed set of parameters for
     """Check the given parameters for validity.
 
     This should check the passed set of parameters for

@@ -186,4 +277,72 @@ class BaseHypervisor(object):
     @raise errors.HypervisorError: when a parameter is not valid
 
     """
     @raise errors.HypervisorError: when a parameter is not valid
 
     """

-    pass
+    for name, (required, _, _, check_fn, errstr) in cls.PARAMETERS.items():
+      value = hvparams[name]
+      if not required and not value:
+        continue
+      if check_fn is not None and not check_fn(value):
+        raise errors.HypervisorError("Parameter '%s' fails"
+                                     " validation: %s (current value: '%s')" %
+                                     (name, errstr, value))
+
+  def GetLinuxNodeInfo(self):
+    """For linux systems, return actual OS information.
+
+    This is an abstraction for all non-hypervisor-based classes, where
+    the node actually sees all the memory and CPUs via the /proc
+    interface and standard commands. The other case if for example
+    xen, where you only see the hardware resources via xen-specific
+    tools.
+
+    @return: a dict with the following keys (values in MiB):
+          - memory_total: the total memory size on the node
+          - memory_free: the available memory on the node for instances
+          - memory_dom0: the memory used by the node itself, if available
+
+    """
+    try:
+      fh = file("/proc/meminfo")
+      try:
+        data = fh.readlines()
+      finally:
+        fh.close()
+    except EnvironmentError, err:
+      raise errors.HypervisorError("Failed to list node info: %s" % (err,))
+
+    result = {}
+    sum_free = 0
+    try:
+      for line in data:
+        splitfields = line.split(":", 1)
+
+        if len(splitfields) > 1:
+          key = splitfields[0].strip()
+          val = splitfields[1].strip()
+          if key == 'MemTotal':
+            result['memory_total'] = int(val.split()[0])/1024
+          elif key in ('MemFree', 'Buffers', 'Cached'):
+            sum_free += int(val.split()[0])/1024
+          elif key == 'Active':
+            result['memory_dom0'] = int(val.split()[0])/1024
+    except (ValueError, TypeError), err:
+      raise errors.HypervisorError("Failed to compute memory usage: %s" %
+                                   (err,))
+    result['memory_free'] = sum_free
+
+    cpu_total = 0
+    try:
+      fh = open("/proc/cpuinfo")
+      try:
+        cpu_total = len(re.findall("(?m)^processor\s*:\s*[0-9]+\s*$",
+                                   fh.read()))
+      finally:
+        fh.close()
+    except EnvironmentError, err:
+      raise errors.HypervisorError("Failed to list node info: %s" % (err,))
+    result['cpu_total'] = cpu_total
+    # FIXME: export correct data here
+    result['cpu_nodes'] = 1
+    result['cpu_sockets'] = 1
+
+    return result