X-Git-Url: https://code.grnet.gr/git/ganeti-local/blobdiff_plain/52b5d2863476953186804a131ca29291f742bb49..a6682fdcc173998be87b77043bfa56c0d12b1ca4:/lib/query.py

diff --git a/lib/query.py b/lib/query.py
index 55dc63f..86940f3 100644
--- a/lib/query.py
+++ b/lib/query.py
@@ -19,7 +19,36 @@
 # 02110-1301, USA.
 
 
-"""Module for query operations"""
+"""Module for query operations
+
+How it works:
+
+  - Add field definitions
+    - See how L{NODE_FIELDS} is built
+    - Each field gets:
+      - Query field definition (L{objects.QueryFieldDefinition}, use
+        L{_MakeField} for creating), containing:
+          - Name, must be lowercase and match L{FIELD_NAME_RE}
+          - Title for tables, must not contain whitespace and match
+            L{TITLE_RE}
+          - Value data type, e.g. L{constants.QFT_NUMBER}
+      - Data request type, see e.g. C{NQ_*}
+      - A retrieval function, see L{Query.__init__} for description
+    - Pass list of fields through L{_PrepareFieldList} for preparation and
+      checks
+  - Instantiate L{Query} with prepared field list definition and selected fields
+  - Call L{Query.RequestedData} to determine what data to collect/compute
+  - Call L{Query.Query} or L{Query.OldStyleQuery} with collected data and use
+    result
+      - Data container must support iteration using C{__iter__}
+      - Items are passed to retrieval functions and can have any format
+  - Call L{Query.GetFields} to get list of definitions for selected fields
+
+@attention: Retrieval functions must be idempotent. They can be called multiple
+  times, in any order and any number of times. This is important to keep in
+  mind for implementing filters in the future.
+
+"""
 
 import logging
 import operator
@@ -33,6 +62,10 @@ from ganeti import objects
 from ganeti import ht
 
 
+# Constants for requesting data from the caller/data provider. Each property
+# collected/computed separately by the data provider should have its own to
+# only collect the requested data and not more.
+
 (NQ_CONFIG,
  NQ_INST,
  NQ_LIVE,
@@ -213,7 +246,7 @@ def _PrepareFieldList(fields):
 
   @type fields: list of tuples; (L{objects.QueryFieldDefinition}, data kind,
     retrieval function)
-  @param fields: List of fields
+  @param fields: List of fields, see L{Query.__init__} for a better description
   @rtype: dict
   @return: Field dictionary for L{Query}
 
@@ -358,7 +391,7 @@ class NodeQueryData:
 
   """
   def __init__(self, nodes, live_data, master_name, node_to_primary,
-               node_to_secondary, groups, oob_support):
+               node_to_secondary, groups, oob_support, cluster):
     """Initializes this class.
 
     """
@@ -369,6 +402,7 @@ class NodeQueryData:
     self.node_to_secondary = node_to_secondary
     self.groups = groups
     self.oob_support = oob_support
+    self.cluster = cluster
 
     # Used for individual rows
     self.curlive_data = None
@@ -415,19 +449,40 @@ _NODE_LIVE_FIELDS = {
   }
 
 
-def _GetNodeGroup(ctx, node):
+def _GetGroup(cb):
+  """Build function for calling another function with an node group.
+
+  @param cb: The callback to be called with the nodegroup
+
+  """
+  def fn(ctx, node):
+    """Get group data for a node.
+
+    @type ctx: L{NodeQueryData}
+    @type inst: L{objects.Node}
+    @param inst: Node object
+
+    """
+    ng = ctx.groups.get(node.group, None)
+    if ng is None:
+      # Nodes always have a group, or the configuration is corrupt
+      return (constants.QRFS_UNAVAIL, None)
+
+    return cb(ctx, node, ng)
+
+  return fn
+
+
+def _GetNodeGroup(ctx, node, ng): # pylint: disable-msg=W0613
   """Returns the name of a node's group.
 
   @type ctx: L{NodeQueryData}
   @type node: L{objects.Node}
   @param node: Node object
+  @type ng: L{objects.NodeGroup}
+  @param ng: The node group this node belongs to
 
   """
-  ng = ctx.groups.get(node.group, None)
-  if ng is None:
-    # Nodes always have a group, or the configuration is corrupt
-    return (constants.QRFS_UNAVAIL, None)
-
   return (constants.QRFS_NORMAL, ng.name)
 
 
@@ -445,6 +500,19 @@ def _GetNodePower(ctx, node):
   return (constants.QRFS_UNAVAIL, None)
 
 
+def _GetNdParams(ctx, node, ng):
+  """Returns the ndparams for this node.
+
+  @type ctx: L{NodeQueryData}
+  @type node: L{objects.Node}
+  @param node: Node object
+  @type ng: L{objects.NodeGroup}
+  @param ng: The node group this node belongs to
+
+  """
+  return (constants.QRFS_NORMAL, ctx.cluster.SimpleFillND(ng.FillND(node)))
+
+
 def _GetLiveNodeField(field, kind, ctx, node):
   """Gets the value of a "live" field from L{NodeQueryData}.
 
@@ -496,11 +564,16 @@ def _BuildNodeFields():
     (_MakeField("role", "Role", constants.QFT_TEXT), NQ_CONFIG,
      lambda ctx, node: (constants.QRFS_NORMAL,
                         _GetNodeRole(node, ctx.master_name))),
-    (_MakeField("group", "Group", constants.QFT_TEXT), NQ_GROUP, _GetNodeGroup),
+    (_MakeField("group", "Group", constants.QFT_TEXT), NQ_GROUP,
+     _GetGroup(_GetNodeGroup)),
     (_MakeField("group.uuid", "GroupUUID", constants.QFT_TEXT),
      NQ_CONFIG, lambda ctx, node: (constants.QRFS_NORMAL, node.group)),
     (_MakeField("powered", "Powered", constants.QFT_BOOL), NQ_OOB,
       _GetNodePower),
+    (_MakeField("ndparams", "NodeParameters", constants.QFT_OTHER), NQ_GROUP,
+      _GetGroup(_GetNdParams)),
+    (_MakeField("custom_ndparams", "CustomNodeParameters", constants.QFT_OTHER),
+      NQ_GROUP, lambda ctx, node: (constants.QRFS_NORMAL, node.ndparams)),
     ]
 
   def _GetLength(getter):
@@ -1117,6 +1190,7 @@ _GROUP_SIMPLE_FIELDS = {
   "name": ("Group", constants.QFT_TEXT),
   "serial_no": ("SerialNo", constants.QFT_NUMBER),
   "uuid": ("UUID", constants.QFT_TEXT),
+  "ndparams": ("NDParams", constants.QFT_OTHER),
   }