Disable synchronous (locking) queries
[ganeti-local] / lib / rpc.py
index f82a90c..70dd312 100644 (file)
 
 import os
 import socket
-import httplib
 import logging
+import zlib
+import base64
 
 from ganeti import utils
 from ganeti import objects
 from ganeti import http
 from ganeti import serializer
 from ganeti import constants
+from ganeti import errors
+
+import ganeti.http.client
 
 
 # Module level variable
@@ -56,7 +60,7 @@ def Init():
 
   assert not _http_manager, "RPC module initialized more than once"
 
-  _http_manager = http.HttpClientManager()
+  _http_manager = http.client.HttpClientManager()
 
 
 def Shutdown():
@@ -72,6 +76,84 @@ def Shutdown():
     _http_manager = None
 
 
+class RpcResult(object):
+  """RPC Result class.
+
+  This class holds an RPC result. It is needed since in multi-node
+  calls we can't raise an exception just because one one out of many
+  failed, and therefore we use this class to encapsulate the result.
+
+  @ivar data: the data payload, for successfull results, or None
+  @type failed: boolean
+  @ivar failed: whether the operation failed at RPC level (not
+      application level on the remote node)
+  @ivar call: the name of the RPC call
+  @ivar node: the name of the node to which we made the call
+  @ivar offline: whether the operation failed because the node was
+      offline, as opposed to actual failure; offline=True will always
+      imply failed=True, in order to allow simpler checking if
+      the user doesn't care about the exact failure mode
+
+  """
+  def __init__(self, data=None, failed=False, offline=False,
+               call=None, node=None):
+    self.failed = failed
+    self.offline = offline
+    self.call = call
+    self.node = node
+    if offline:
+      self.failed = True
+      self.error = "Node is marked offline"
+      self.data = self.payload = None
+    elif failed:
+      self.error = data
+      self.data = self.payload = None
+    else:
+      self.data = data
+      self.error = None
+      if isinstance(data, (tuple, list)) and len(data) == 2:
+        self.payload = data[1]
+      else:
+        self.payload = None
+
+  def Raise(self):
+    """If the result has failed, raise an OpExecError.
+
+    This is used so that LU code doesn't have to check for each
+    result, but instead can call this function.
+
+    """
+    if self.failed:
+      raise errors.OpExecError("Call '%s' to node '%s' has failed: %s" %
+                               (self.call, self.node, self.error))
+
+  def RemoteFailMsg(self):
+    """Check if the remote procedure failed.
+
+    This is valid only for RPC calls which return result of the form
+    (status, data | error_msg).
+
+    @return: empty string for succcess, otherwise an error message
+
+    """
+    def _EnsureErr(val):
+      """Helper to ensure we return a 'True' value for error."""
+      if val:
+        return val
+      else:
+        return "No error information"
+
+    if self.failed:
+      return _EnsureErr(self.error)
+    if not isinstance(self.data, (tuple, list)):
+      return "Invalid result type (%s)" % type(self.data)
+    if len(self.data) != 2:
+      return "Invalid result length (%d), expected 2" % len(self.data)
+    if not self.data[0]:
+      return _EnsureErr(self.data[1])
+    return ""
+
+
 class Client:
   """RPC Client class.
 
@@ -84,12 +166,10 @@ class Client:
   cause bugs.
 
   """
-  def __init__(self, procedure, args):
+  def __init__(self, procedure, body, port):
     self.procedure = procedure
-    self.args = args
-    self.body = serializer.DumpJson(args, indent=False)
-
-    self.port = utils.GetNodeDaemonPort()
+    self.body = body
+    self.port = port
     self.nc = {}
 
     self._ssl_params = \
@@ -126,17 +206,18 @@ class Client:
     if address is None:
       address = name
 
-    self.nc[name] = http.HttpClientRequest(address, self.port, http.HTTP_PUT,
-                                           "/%s" % self.procedure,
-                                           post_data=self.body,
-                                           ssl_params=self._ssl_params,
-                                           ssl_verify_peer=True)
+    self.nc[name] = \
+      http.client.HttpClientRequest(address, self.port, http.HTTP_PUT,
+                                    "/%s" % self.procedure,
+                                    post_data=self.body,
+                                    ssl_params=self._ssl_params,
+                                    ssl_verify_peer=True)
 
   def GetResults(self):
     """Call nodes and return results.
 
     @rtype: list
-    @returns: List of RPC results
+    @return: List of RPC results
 
     """
     assert _http_manager, "RPC module not intialized"
@@ -146,8 +227,9 @@ class Client:
     results = {}
 
     for name, req in self.nc.iteritems():
-      if req.success and req.resp_status == http.HTTP_OK:
-        results[name] = serializer.LoadJson(req.resp_body)
+      if req.success and req.resp_status_code == http.HTTP_OK:
+        results[name] = RpcResult(data=serializer.LoadJson(req.resp_body),
+                                  node=name, call=self.procedure)
         continue
 
       # TODO: Better error reporting
@@ -156,8 +238,10 @@ class Client:
       else:
         msg = req.resp_body
 
-      logging.error("RPC error from node %s: %s", name, msg)
-      results[name] = False
+      logging.error("RPC error in %s from node %s: %s",
+                    self.procedure, name, msg)
+      results[name] = RpcResult(data=msg, failed=True, node=name,
+                                call=self.procedure)
 
     return results
 
@@ -174,6 +258,7 @@ class RpcRunner(object):
 
     """
     self._cfg = cfg
+    self.port = utils.GetNodeDaemonPort()
 
   def _InstDict(self, instance):
     """Convert the given instance to a dict.
@@ -194,73 +279,123 @@ class RpcRunner(object):
     idict["beparams"] = cluster.FillBE(instance)
     return idict
 
-  def _ConnectList(self, client, node_list):
+  def _ConnectList(self, client, node_list, call):
     """Helper for computing node addresses.
 
     @type client: L{Client}
     @param client: a C{Client} instance
     @type node_list: list
     @param node_list: the node list we should connect
+    @type call: string
+    @param call: the name of the remote procedure call, for filling in
+        correctly any eventual offline nodes' results
 
     """
     all_nodes = self._cfg.GetAllNodesInfo()
+    name_list = []
     addr_list = []
+    skip_dict = {}
     for node in node_list:
       if node in all_nodes:
+        if all_nodes[node].offline:
+          skip_dict[node] = RpcResult(node=node, offline=True, call=call)
+          continue
         val = all_nodes[node].primary_ip
       else:
         val = None
       addr_list.append(val)
-    client.ConnectList(node_list, address_list=addr_list)
+      name_list.append(node)
+    if name_list:
+      client.ConnectList(name_list, address_list=addr_list)
+    return skip_dict
 
-  def _ConnectNode(self, client, node):
+  def _ConnectNode(self, client, node, call):
     """Helper for computing one node's address.
 
     @type client: L{Client}
     @param client: a C{Client} instance
     @type node: str
     @param node: the node we should connect
+    @type call: string
+    @param call: the name of the remote procedure call, for filling in
+        correctly any eventual offline nodes' results
 
     """
     node_info = self._cfg.GetNodeInfo(node)
     if node_info is not None:
+      if node_info.offline:
+        return RpcResult(node=node, offline=True, call=call)
       addr = node_info.primary_ip
     else:
       addr = None
     client.ConnectNode(node, address=addr)
 
-  def _MultiNodeCall(self, node_list, procedure, args,
-                     address_list=None):
-    c = Client(procedure, args)
-    if address_list is None:
-      self._ConnectList(c, node_list)
-    else:
-      c.ConnectList(node_list, address_list=address_list)
-    return c.GetResults()
+  def _MultiNodeCall(self, node_list, procedure, args):
+    """Helper for making a multi-node call
+
+    """
+    body = serializer.DumpJson(args, indent=False)
+    c = Client(procedure, body, self.port)
+    skip_dict = self._ConnectList(c, node_list, procedure)
+    skip_dict.update(c.GetResults())
+    return skip_dict
 
   @classmethod
   def _StaticMultiNodeCall(cls, node_list, procedure, args,
                            address_list=None):
-    c = Client(procedure, args)
+    """Helper for making a multi-node static call
+
+    """
+    body = serializer.DumpJson(args, indent=False)
+    c = Client(procedure, body, utils.GetNodeDaemonPort())
     c.ConnectList(node_list, address_list=address_list)
     return c.GetResults()
 
   def _SingleNodeCall(self, node, procedure, args):
-    """
+    """Helper for making a single-node call
 
     """
-    c = Client(procedure, args)
-    self._ConnectNode(c, node)
-    return c.GetResults().get(node, False)
+    body = serializer.DumpJson(args, indent=False)
+    c = Client(procedure, body, self.port)
+    result = self._ConnectNode(c, node, procedure)
+    if result is None:
+      # we did connect, node is not offline
+      result = c.GetResults()[node]
+    return result
 
   @classmethod
   def _StaticSingleNodeCall(cls, node, procedure, args):
+    """Helper for making a single-node static call
+
     """
+    body = serializer.DumpJson(args, indent=False)
+    c = Client(procedure, body, utils.GetNodeDaemonPort())
+    c.ConnectNode(node)
+    return c.GetResults()[node]
+
+  @staticmethod
+  def _Compress(data):
+    """Compresses a string for transport over RPC.
+
+    Small amounts of data are not compressed.
+
+    @type data: str
+    @param data: Data
+    @rtype: tuple
+    @return: Encoded data to send
 
     """
-    c = Client(procedure, args)
-    c.ConnectNode(c, node)
-    return c.GetResults().get(node, False)
+    # Small amounts of data are not compressed
+    if len(data) < 512:
+      return (constants.RPC_ENCODING_NONE, data)
+
+    # Compress with zlib and encode in base64
+    return (constants.RPC_ENCODING_ZLIB_BASE64,
+            base64.b64encode(zlib.compress(data, 3)))
+
+  #
+  # Begin RPC calls
+  #
 
   def call_volume_list(self, node_list, vg_name):
     """Gets the logical volumes present in a given volume group.
@@ -290,14 +425,14 @@ class RpcRunner(object):
     """
     return self._SingleNodeCall(node, "bridges_exist", [bridges_list])
 
-  def call_instance_start(self, node, instance, extra_args):
+  def call_instance_start(self, node, instance):
     """Starts an instance.
 
     This is a single-node call.
 
     """
     return self._SingleNodeCall(node, "instance_start",
-                                [self._InstDict(instance), extra_args])
+                                [self._InstDict(instance)])
 
   def call_instance_shutdown(self, node, instance):
     """Stops an instance.
@@ -308,6 +443,59 @@ class RpcRunner(object):
     return self._SingleNodeCall(node, "instance_shutdown",
                                 [self._InstDict(instance)])
 
+  def call_migration_info(self, node, instance):
+    """Gather the information necessary to prepare an instance migration.
+
+    This is a single-node call.
+
+    @type node: string
+    @param node: the node on which the instance is currently running
+    @type instance: C{objects.Instance}
+    @param instance: the instance definition
+
+    """
+    return self._SingleNodeCall(node, "migration_info",
+                                [self._InstDict(instance)])
+
+  def call_accept_instance(self, node, instance, info, target):
+    """Prepare a node to accept an instance.
+
+    This is a single-node call.
+
+    @type node: string
+    @param node: the target node for the migration
+    @type instance: C{objects.Instance}
+    @param instance: the instance definition
+    @type info: opaque/hypervisor specific (string/data)
+    @param info: result for the call_migration_info call
+    @type target: string
+    @param target: target hostname (usually ip address) (on the node itself)
+
+    """
+    return self._SingleNodeCall(node, "accept_instance",
+                                [self._InstDict(instance), info, target])
+
+  def call_finalize_migration(self, node, instance, info, success):
+    """Finalize any target-node migration specific operation.
+
+    This is called both in case of a successful migration and in case of error
+    (in which case it should abort the migration).
+
+    This is a single-node call.
+
+    @type node: string
+    @param node: the target node for the migration
+    @type instance: C{objects.Instance}
+    @param instance: the instance definition
+    @type info: opaque/hypervisor specific (string/data)
+    @param info: result for the call_migration_info call
+    @type success: boolean
+    @param success: whether the migration was a success or a failure
+
+    """
+    return self._SingleNodeCall(node, "finalize_migration",
+                                [self._InstDict(instance), info, success])
+
   def call_instance_migrate(self, node, instance, target, live):
     """Migrate an instance.
 
@@ -327,15 +515,14 @@ class RpcRunner(object):
     return self._SingleNodeCall(node, "instance_migrate",
                                 [self._InstDict(instance), target, live])
 
-  def call_instance_reboot(self, node, instance, reboot_type, extra_args):
+  def call_instance_reboot(self, node, instance, reboot_type):
     """Reboots an instance.
 
     This is a single-node call.
 
     """
     return self._SingleNodeCall(node, "instance_reboot",
-                                [self._InstDict(instance), reboot_type,
-                                 extra_args])
+                                [self._InstDict(instance), reboot_type])
 
   def call_instance_os_add(self, node, inst):
     """Installs an OS on the given instance.
@@ -370,6 +557,20 @@ class RpcRunner(object):
     """
     return self._SingleNodeCall(node, "instance_info", [instance, hname])
 
+  def call_instance_migratable(self, node, instance):
+    """Checks whether the given instance can be migrated.
+
+    This is a single-node call.
+
+    @param node: the node to query
+    @type instance: L{objects.Instance}
+    @param instance: the instance to check
+
+
+    """
+    return self._SingleNodeCall(node, "instance_migratable",
+                                [self._InstDict(instance)])
+
   def call_all_instances_info(self, node_list, hypervisor_list):
     """Returns information about all instances on the given nodes.
 
@@ -426,8 +627,8 @@ class RpcRunner(object):
 
     @type node_list: list
     @param node_list: the list of nodes to query
-    @type vgname: C{string}
-    @param vgname: the name of the volume group to ask for disk space
+    @type vg_name: C{string}
+    @param vg_name: 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
@@ -437,19 +638,21 @@ class RpcRunner(object):
     retux = self._MultiNodeCall(node_list, "node_info",
                                 [vg_name, hypervisor_type])
 
-    for node_name in retux:
-      ret = retux.get(node_name, False)
-      if type(ret) != dict:
-        logging.error("could not connect to node %s", node_name)
-        ret = {}
-
-      utils.CheckDict(ret, {
-                        'memory_total' : '-',
-                        'memory_dom0' : '-',
-                        'memory_free' : '-',
-                        'vg_size' : 'node_unreachable',
-                        'vg_free' : '-',
-                      }, "call_node_info")
+    for result in retux.itervalues():
+      if result.failed or not isinstance(result.data, dict):
+        result.data = {}
+      if result.offline:
+        log_name = None
+      else:
+        log_name = "call_node_info"
+
+      utils.CheckDict(result.data, {
+        'memory_total' : '-',
+        'memory_dom0' : '-',
+        'memory_free' : '-',
+        'vg_size' : 'node_unreachable',
+        'vg_free' : '-',
+        }, log_name)
     return retux
 
   def call_node_add(self, node, dsa, dsapub, rsa, rsapub, ssh, sshpub):
@@ -587,14 +790,43 @@ class RpcRunner(object):
     """
     return self._SingleNodeCall(node, "blockdev_find", [disk.ToDict()])
 
-  def call_blockdev_close(self, node, disks):
+  def call_blockdev_close(self, node, instance_name, disks):
     """Closes the given block devices.
 
     This is a single-node call.
 
     """
-    return self._SingleNodeCall(node, "blockdev_close",
-                                [cf.ToDict() for cf in disks])
+    params = [instance_name, [cf.ToDict() for cf in disks]]
+    return self._SingleNodeCall(node, "blockdev_close", params)
+
+  def call_drbd_disconnect_net(self, node_list, nodes_ip, disks):
+    """Disconnects the network of the given drbd devices.
+
+    This is a multi-node call.
+
+    """
+    return self._MultiNodeCall(node_list, "drbd_disconnect_net",
+                               [nodes_ip, [cf.ToDict() for cf in disks]])
+
+  def call_drbd_attach_net(self, node_list, nodes_ip,
+                           disks, instance_name, multimaster):
+    """Disconnects the given drbd devices.
+
+    This is a multi-node call.
+
+    """
+    return self._MultiNodeCall(node_list, "drbd_attach_net",
+                               [nodes_ip, [cf.ToDict() for cf in disks],
+                                instance_name, multimaster])
+
+  def call_drbd_wait_sync(self, node_list, nodes_ip, disks):
+    """Waits for the synchronization of drbd devices is complete.
+
+    This is a multi-node call.
+
+    """
+    return self._MultiNodeCall(node_list, "drbd_wait_sync",
+                               [nodes_ip, [cf.ToDict() for cf in disks]])
 
   @classmethod
   def call_upload_file(cls, node_list, file_name, address_list=None):
@@ -614,7 +846,8 @@ class RpcRunner(object):
         to optimize the RPC speed
 
     """
-    data = utils.ReadFile(file_name)
+    file_contents = utils.ReadFile(file_name)
+    data = cls._Compress(file_contents)
     st = os.stat(file_name)
     params = [file_name, data, st.st_mode, st.st_uid, st.st_gid,
               st.st_atime, st.st_mtime]
@@ -622,13 +855,13 @@ class RpcRunner(object):
                                     address_list=address_list)
 
   @classmethod
-  def call_write_ssconf_files(cls, node_list):
+  def call_write_ssconf_files(cls, node_list, values):
     """Write ssconf files.
 
     This is a multi-node call.
 
     """
-    return cls._StaticMultiNodeCall(node_list, "write_ssconf_files", [])
+    return cls._StaticMultiNodeCall(node_list, "write_ssconf_files", [values])
 
   def call_os_diagnose(self, node_list):
     """Request a diagnose of OS definitions.
@@ -638,14 +871,11 @@ class RpcRunner(object):
     """
     result = self._MultiNodeCall(node_list, "os_diagnose", [])
 
-    new_result = {}
-    for node_name in result:
-      if result[node_name]:
-        nr = [objects.OS.FromDict(oss) for oss in result[node_name]]
-      else:
-        nr = []
-      new_result[node_name] = nr
-    return new_result
+    for node_result in result.values():
+      if not node_result.failed and node_result.data:
+        node_result.data = [objects.OS.FromDict(oss)
+                            for oss in node_result.data]
+    return result
 
   def call_os_get(self, node, name):
     """Returns an OS definition.
@@ -654,10 +884,9 @@ class RpcRunner(object):
 
     """
     result = self._SingleNodeCall(node, "os_get", [name])
-    if isinstance(result, dict):
-      return objects.OS.FromDict(result)
-    else:
-      return result
+    if not result.failed and isinstance(result.data, dict):
+      result.data = objects.OS.FromDict(result.data)
+    return result
 
   def call_hooks_runner(self, node_list, hpath, phase, env):
     """Call the hooks runner.
@@ -734,9 +963,9 @@ class RpcRunner(object):
 
     """
     result = self._SingleNodeCall(node, "export_info", [path])
-    if not result:
-      return result
-    return objects.SerializableConfigParser.Loads(str(result))
+    if not result.failed and result.data:
+      result.data = objects.SerializableConfigParser.Loads(str(result.data))
+    return result
 
   def call_instance_os_import(self, node, inst, src_node, src_images,
                               cluster_name):
@@ -785,6 +1014,14 @@ class RpcRunner(object):
     """
     return self._MultiNodeCall(node_list, "node_volumes", [])
 
+  def call_node_demote_from_mc(self, node):
+    """Demote a node from the master candidate role.
+
+    This is a single-node call.
+
+    """
+    return self._SingleNodeCall(node, "node_demote_from_mc", [])
+
   def call_test_delay(self, node_list, duration):
     """Sleep for a fixed time on given node(s).
 
@@ -829,7 +1066,7 @@ class RpcRunner(object):
 
     """
     return cls._StaticMultiNodeCall(node_list, "jobqueue_update",
-                                    [file_name, content],
+                                    [file_name, cls._Compress(content)],
                                     address_list=address_list)
 
   @classmethod
@@ -842,13 +1079,13 @@ class RpcRunner(object):
     return cls._StaticSingleNodeCall(node, "jobqueue_purge", [])
 
   @classmethod
-  def call_jobqueue_rename(cls, node_list, address_list, old, new):
+  def call_jobqueue_rename(cls, node_list, address_list, rename):
     """Rename a job queue file.
 
     This is a multi-node call.
 
     """
-    return cls._StaticMultiNodeCall(node_list, "jobqueue_rename", [old, new],
+    return cls._StaticMultiNodeCall(node_list, "jobqueue_rename", rename,
                                     address_list=address_list)
 
   @classmethod