Add a new NodeGroup config object

[ganeti-local] / lib / luxi.py

diff --git a/lib/luxi.py b/lib/luxi.py
index 2a3adaa..669c3dd 100644 (file)
--- a/lib/luxi.py
+++ b/lib/luxi.py
@@ -33,14 +33,16 @@ import socket
 import collections
 import time
 import errno
 import collections
 import time
 import errno

+import logging

 
 from ganeti import serializer
 from ganeti import constants
 from ganeti import errors
 
 from ganeti import serializer
 from ganeti import constants
 from ganeti import errors

+from ganeti import utils

 
 
 
 

-KEY_METHOD = 'method'
-KEY_ARGS = 'args'
+KEY_METHOD = "method"
+KEY_ARGS = "args"

 KEY_SUCCESS = "success"
 KEY_RESULT = "result"
 
 KEY_SUCCESS = "success"
 KEY_RESULT = "result"
 

@@ -56,35 +58,32 @@ REQ_QUERY_NODES = "QueryNodes"
 REQ_QUERY_EXPORTS = "QueryExports"
 REQ_QUERY_CONFIG_VALUES = "QueryConfigValues"
 REQ_QUERY_CLUSTER_INFO = "QueryClusterInfo"
 REQ_QUERY_EXPORTS = "QueryExports"
 REQ_QUERY_CONFIG_VALUES = "QueryConfigValues"
 REQ_QUERY_CLUSTER_INFO = "QueryClusterInfo"

+REQ_QUERY_TAGS = "QueryTags"
+REQ_QUERY_LOCKS = "QueryLocks"

 REQ_QUEUE_SET_DRAIN_FLAG = "SetDrainFlag"
 REQ_SET_WATCHER_PAUSE = "SetWatcherPause"
 
 DEF_CTMO = 10
 DEF_RWTO = 60
 
 REQ_QUEUE_SET_DRAIN_FLAG = "SetDrainFlag"
 REQ_SET_WATCHER_PAUSE = "SetWatcherPause"
 
 DEF_CTMO = 10
 DEF_RWTO = 60
 

+# WaitForJobChange timeout
+WFJC_TIMEOUT = (DEF_RWTO - 1) / 2

 
 

-class ProtocolError(Exception):
-  """Denotes an error in the server communication"""
+
+class ProtocolError(errors.GenericError):
+  """Denotes an error in the LUXI protocol."""

 
 
 class ConnectionClosedError(ProtocolError):
 
 
 class ConnectionClosedError(ProtocolError):

-  """Connection closed error"""
+  """Connection closed error."""

 
 
 class TimeoutError(ProtocolError):
 
 
 class TimeoutError(ProtocolError):

-  """Operation timeout error"""
-
-
-class EncodingError(ProtocolError):
-  """Encoding failure on the sending side"""
-
-
-class DecodingError(ProtocolError):
-  """Decoding failure on the receiving side"""
+  """Operation timeout error."""

 
 
 class RequestError(ProtocolError):
 
 
 class RequestError(ProtocolError):

-  """Error on request
+  """Error on request.

 
   This signifies an error in the request format or request handling,
   but not (e.g.) an error in starting up an instance.
 
   This signifies an error in the request format or request handling,
   but not (e.g.) an error in starting up an instance.

@@ -97,7 +96,7 @@ class RequestError(ProtocolError):
 
 
 class NoMasterError(ProtocolError):
 
 
 class NoMasterError(ProtocolError):

-  """The master cannot be reached
+  """The master cannot be reached.

 
   This means that the master daemon is not running or the socket has
   been removed.
 
   This means that the master daemon is not running or the socket has
   been removed.

@@ -105,6 +104,14 @@ class NoMasterError(ProtocolError):
   """
 
 
   """
 
 

+class PermissionError(ProtocolError):
+  """Permission denied while connecting to the master socket.
+
+  This means the user doesn't have the proper rights.
+
+  """
+
+

 class Transport:
   """Low-level transport class.
 
 class Transport:
   """Low-level transport class.
 

@@ -117,15 +124,12 @@ class Transport:
 
   """
 
 
   """
 

-  def __init__(self, address, timeouts=None, eom=None):
+  def __init__(self, address, timeouts=None):

     """Constructor for the Client class.
 
     Arguments:
       - address: a valid address the the used transport class
       - timeout: a list of timeouts, to be used on connect and read/write
     """Constructor for the Client class.
 
     Arguments:
       - address: a valid address the the used transport class
       - timeout: a list of timeouts, to be used on connect and read/write

-      - eom: an identifier to be used as end-of-message which the
-        upper-layer will guarantee that this identifier will not appear
-        in any message

 
     There are two timeouts used since we might want to wait for a long
     time for a response, but the connect timeout should be lower.
 
     There are two timeouts used since we might want to wait for a long
     time for a response, but the connect timeout should be lower.

@@ -148,22 +152,16 @@ class Transport:
     self._buffer = ""
     self._msgs = collections.deque()
 
     self._buffer = ""
     self._msgs = collections.deque()
 

-    if eom is None:
-      self.eom = '\3'
-    else:
-      self.eom = eom
-

     try:
       self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
     try:
       self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)

-      self.socket.settimeout(self._ctimeout)
+
+      # Try to connect

       try:
       try:

-        self.socket.connect(address)
-      except socket.timeout, err:
-        raise TimeoutError("Connect timed out: %s" % str(err))
-      except socket.error, err:
-        if err.args[0] in (errno.ENOENT, errno.ECONNREFUSED):
-          raise NoMasterError((address,))
-        raise
+        utils.Retry(self._Connect, 1.0, self._ctimeout,
+                    args=(self.socket, address, self._ctimeout))
+      except utils.RetryTimeout:
+        raise TimeoutError("Connect timed out")
+

       self.socket.settimeout(self._rwtimeout)
     except (socket.error, NoMasterError):
       if self.socket is not None:
       self.socket.settimeout(self._rwtimeout)
     except (socket.error, NoMasterError):
       if self.socket is not None:

@@ -171,6 +169,24 @@ class Transport:
       self.socket = None
       raise
 
       self.socket = None
       raise
 

+  @staticmethod
+  def _Connect(sock, address, timeout):
+    sock.settimeout(timeout)
+    try:
+      sock.connect(address)
+    except socket.timeout, err:
+      raise TimeoutError("Connect timed out: %s" % str(err))
+    except socket.error, err:
+      error_code = err.args[0]
+      if error_code in (errno.ENOENT, errno.ECONNREFUSED):
+        raise NoMasterError(address)
+      elif error_code in (errno.EPERM, errno.EACCES):
+        raise PermissionError(address)
+      elif error_code == errno.EAGAIN:
+        # Server's socket backlog is full at the moment
+        raise utils.RetryAgain()
+      raise
+

   def _CheckSocket(self):
     """Make sure we are connected.
 
   def _CheckSocket(self):
     """Make sure we are connected.
 

@@ -184,12 +200,13 @@ class Transport:
     This just sends a message and doesn't wait for the response.
 
     """
     This just sends a message and doesn't wait for the response.
 
     """

-    if self.eom in msg:
-      raise EncodingError("Message terminator found in payload")
+    if constants.LUXI_EOM in msg:
+      raise ProtocolError("Message terminator found in payload")
+

     self._CheckSocket()
     try:
       # TODO: sendall is not guaranteed to send everything
     self._CheckSocket()
     try:
       # TODO: sendall is not guaranteed to send everything

-      self.socket.sendall(msg + self.eom)
+      self.socket.sendall(msg + constants.LUXI_EOM)

     except socket.timeout, err:
       raise TimeoutError("Sending timeout: %s" % str(err))
 
     except socket.timeout, err:
       raise TimeoutError("Sending timeout: %s" % str(err))
 

@@ -219,7 +236,7 @@ class Transport:
         break
       if not data:
         raise ConnectionClosedError("Connection closed while reading")
         break
       if not data:
         raise ConnectionClosedError("Connection closed while reading")

-      new_msgs = (self._buffer + data).split(self.eom)
+      new_msgs = (self._buffer + data).split(constants.LUXI_EOM)

       self._buffer = new_msgs.pop()
       self._msgs.extend(new_msgs)
     return self._msgs.popleft()
       self._buffer = new_msgs.pop()
       self._msgs.extend(new_msgs)
     return self._msgs.popleft()

@@ -240,6 +257,99 @@ class Transport:
       self.socket = None
 
 
       self.socket = None
 
 

+def ParseRequest(msg):
+  """Parses a LUXI request message.
+
+  """
+  try:
+    request = serializer.LoadJson(msg)
+  except ValueError, err:
+    raise ProtocolError("Invalid LUXI request (parsing error): %s" % err)
+
+  logging.debug("LUXI request: %s", request)
+
+  if not isinstance(request, dict):
+    logging.error("LUXI request not a dict: %r", msg)
+    raise ProtocolError("Invalid LUXI request (not a dict)")
+
+  method = request.get(KEY_METHOD, None) # pylint: disable-msg=E1103
+  args = request.get(KEY_ARGS, None) # pylint: disable-msg=E1103
+
+  if method is None or args is None:
+    logging.error("LUXI request missing method or arguments: %r", msg)
+    raise ProtocolError(("Invalid LUXI request (no method or arguments"
+                         " in request): %r") % msg)
+
+  return (method, args)
+
+
+def ParseResponse(msg):
+  """Parses a LUXI response message.
+
+  """
+  # Parse the result
+  try:
+    data = serializer.LoadJson(msg)
+  except Exception, err:
+    raise ProtocolError("Error while deserializing response: %s" % str(err))
+
+  # Validate response
+  if not (isinstance(data, dict) and
+          KEY_SUCCESS in data and
+          KEY_RESULT in data):
+    raise ProtocolError("Invalid response from server: %r" % data)
+
+  return (data[KEY_SUCCESS], data[KEY_RESULT])
+
+
+def FormatResponse(success, result):
+  """Formats a LUXI response message.
+
+  """
+  response = {
+    KEY_SUCCESS: success,
+    KEY_RESULT: result,
+    }
+
+  logging.debug("LUXI response: %s", response)
+
+  return serializer.DumpJson(response)
+
+
+def FormatRequest(method, args):
+  """Formats a LUXI request message.
+
+  """
+  # Build request
+  request = {
+    KEY_METHOD: method,
+    KEY_ARGS: args,
+    }
+
+  # Serialize the request
+  return serializer.DumpJson(request, indent=False)
+
+
+def CallLuxiMethod(transport_cb, method, args):
+  """Send a LUXI request via a transport and return the response.
+
+  """
+  assert callable(transport_cb)
+
+  request_msg = FormatRequest(method, args)
+
+  # Send request and wait for response
+  response_msg = transport_cb(request_msg)
+
+  (success, result) = ParseResponse(response_msg)
+
+  if success:
+    return result
+
+  errors.MaybeRaise(result)
+  raise RequestError(result)
+
+

 class Client(object):
   """High-level client implementation.
 
 class Client(object):
   """High-level client implementation.
 

@@ -286,49 +396,23 @@ class Client(object):
       old_transp = self.transport
       self.transport = None
       old_transp.Close()
       old_transp = self.transport
       self.transport = None
       old_transp.Close()

-    except Exception:
+    except Exception: # pylint: disable-msg=W0703

       pass
 
       pass
 

-  def CallMethod(self, method, args):
-    """Send a generic request and return the response.
-
-    """
-    # Build request
-    request = {
-      KEY_METHOD: method,
-      KEY_ARGS: args,
-      }
-
-    # Serialize the request
-    send_data = serializer.DumpJson(request, indent=False)
-
+  def _SendMethodCall(self, data):

     # Send request and wait for response
     try:
       self._InitTransport()
     # Send request and wait for response
     try:
       self._InitTransport()

-      result = self.transport.Call(send_data)
+      return self.transport.Call(data)

     except Exception:
       self._CloseTransport()
       raise
 
     except Exception:
       self._CloseTransport()
       raise
 

-    # Parse the result
-    try:
-      data = serializer.LoadJson(result)
-    except Exception, err:
-      raise ProtocolError("Error while deserializing response: %s" % str(err))
-
-    # Validate response
-    if (not isinstance(data, dict) or
-        KEY_SUCCESS not in data or
-        KEY_RESULT not in data):
-      raise DecodingError("Invalid response from server: %s" % str(data))
-
-    result = data[KEY_RESULT]
-
-    if not data[KEY_SUCCESS]:
-      errors.MaybeRaise(result)
-      raise RequestError(result)
+  def CallMethod(self, method, args):
+    """Send a generic request and return the response.

 
 

-    return result
+    """
+    return CallLuxiMethod(self._SendMethodCall, method, args)

 
   def SetQueueDrainFlag(self, drain_flag):
     return self.CallMethod(REQ_QUEUE_SET_DRAIN_FLAG, drain_flag)
 
   def SetQueueDrainFlag(self, drain_flag):
     return self.CallMethod(REQ_QUEUE_SET_DRAIN_FLAG, drain_flag)

@@ -356,12 +440,33 @@ class Client(object):
     timeout = (DEF_RWTO - 1) / 2
     return self.CallMethod(REQ_AUTOARCHIVE_JOBS, (age, timeout))
 
     timeout = (DEF_RWTO - 1) / 2
     return self.CallMethod(REQ_AUTOARCHIVE_JOBS, (age, timeout))
 

+  def WaitForJobChangeOnce(self, job_id, fields,
+                           prev_job_info, prev_log_serial,
+                           timeout=WFJC_TIMEOUT):
+    """Waits for changes on a job.
+
+    @param job_id: Job ID
+    @type fields: list
+    @param fields: List of field names to be observed
+    @type prev_job_info: None or list
+    @param prev_job_info: Previously received job information
+    @type prev_log_serial: None or int/long
+    @param prev_log_serial: Highest log serial number previously received
+    @type timeout: int/float
+    @param timeout: Timeout in seconds (values larger than L{WFJC_TIMEOUT} will
+                    be capped to that value)
+
+    """
+    assert timeout >= 0, "Timeout can not be negative"
+    return self.CallMethod(REQ_WAIT_FOR_JOB_CHANGE,
+                           (job_id, fields, prev_job_info,
+                            prev_log_serial,
+                            min(WFJC_TIMEOUT, timeout)))
+

   def WaitForJobChange(self, job_id, fields, prev_job_info, prev_log_serial):
   def WaitForJobChange(self, job_id, fields, prev_job_info, prev_log_serial):

-    timeout = (DEF_RWTO - 1) / 2

     while True:
     while True:

-      result = self.CallMethod(REQ_WAIT_FOR_JOB_CHANGE,
-                               (job_id, fields, prev_job_info,
-                                prev_log_serial, timeout))
+      result = self.WaitForJobChangeOnce(job_id, fields,
+                                         prev_job_info, prev_log_serial)

       if result != constants.JOB_NOTCHANGED:
         break
     return result
       if result != constants.JOB_NOTCHANGED:
         break
     return result

@@ -384,5 +489,8 @@ class Client(object):
   def QueryConfigValues(self, fields):
     return self.CallMethod(REQ_QUERY_CONFIG_VALUES, fields)
 
   def QueryConfigValues(self, fields):
     return self.CallMethod(REQ_QUERY_CONFIG_VALUES, fields)
 

+  def QueryTags(self, kind, name):
+    return self.CallMethod(REQ_QUERY_TAGS, (kind, name))

 
 

-# TODO: class Server(object)
+  def QueryLocks(self, fields, sync):
+    return self.CallMethod(REQ_QUERY_LOCKS, (fields, sync))