Start renaming UUID into NID, because node IDs are not 128 bits length anymore

SQL tables can be upgraded using:
  UPDATE config SET name = 'nid' WHERE name = 'uuid';

then for MySQL:
  ALTER TABLE pt CHANGE uuid nid INT NOT NULL;

or SQLite:
  ALTER TABLE pt RENAME TO old_pt;
  CREATE TABLE pt (rid INTEGER NOT NULL, nid INTEGER NOT NULL, state INTEGER NOT NULL, PRIMARY KEY (rid, nid));
  INSERT INTO pt SELECT * from old_pt;
  DROP TABLE old_pt;

TODO

@@ -23,6 +23,7 @@ RC  - Review output of pylint (CODE)
       Consider the need to implement a keep-alive system (packets sent
       automatically when there is no activity on the connection for a period
       of time).
+    - Finish renaming UUID into NID everywhere (CODE)
     - Consider using multicast for cluster-wide notifications. (BANDWITH)
       Currently, multi-receivers notifications are sent in unicast to each
       receiver. Multicast should be used.

UPGRADE

@@ -19,11 +19,11 @@ SQL commands to migrate each storage from NEO 0.10.x::
   UPDATE trans SET ttid=tid;
   ALTER TABLE ttrans ADD COLUMN ttid BIGINT UNSIGNED NOT NULL;
   ALTER TABLE config MODIFY name VARBINARY(255) NOT NULL;
-  CREATE TEMPORARY TABLE uuid (new INT NOT NULL AUTO_INCREMENT PRIMARY KEY, old CHAR(32) NOT NULL, KEY (old)) ENGINE = InnoDB SELECT DISTINCT uuid as old FROM pt ORDER BY uuid;
-  ALTER TABLE pt DROP PRIMARY KEY, CHANGE uuid old CHAR(32) NOT NULL, ADD uuid INT NOT NULL after rid;
-  UPDATE pt, uuid SET pt.uuid=uuid.new, state=state-1 WHERE pt.old=uuid.old;
-  ALTER TABLE pt DROP old, ADD PRIMARY KEY (rid, uuid);
-  UPDATE config, uuid SET config.value=uuid.new WHERE config.name='uuid' AND uuid.old=config.value;
+  CREATE TEMPORARY TABLE nid (new INT NOT NULL AUTO_INCREMENT PRIMARY KEY, old CHAR(32) NOT NULL, KEY (old)) ENGINE = InnoDB SELECT DISTINCT uuid as old FROM pt ORDER BY uuid;
+  ALTER TABLE pt DROP PRIMARY KEY, ADD nid INT NOT NULL after rid;
+  UPDATE pt, nid SET pt.nid=nid.new, state=state-1 WHERE pt.uuid=nid.old;
+  ALTER TABLE pt DROP uuid, ADD PRIMARY KEY (rid, nid);
+  UPDATE config, nid SET config.name='nid', config.value=nid.new WHERE config.name='uuid' AND nid.old=config.value;
   DELETE FROM config WHERE name='loid';
 
 NEO 0.10

neo/storage/database/manager.py

@@ -72,17 +72,17 @@ class DatabaseManager(object):
 
     def getUUID(self):
         """
-            Load an UUID from a database.
+            Load a NID from a database.
         """
-        uuid = self.getConfiguration('uuid')
-        if uuid is not None:
-            return int(uuid)
+        nid = self.getConfiguration('nid')
+        if nid is not None:
+            return int(nid)
 
-    def setUUID(self, uuid):
+    def setUUID(self, nid):
         """
-            Store an UUID into a database.
+            Store a NID into a database.
         """
-        self.setConfiguration('uuid', str(uuid))
+        self.setConfiguration('nid', str(nid))
 
     def getNumPartitions(self):
         """
@@ -151,7 +151,7 @@ class DatabaseManager(object):
 
     def getPartitionTable(self):
         """Return a whole partition table as a sequence of rows. Each row
-        is again a tuple of an offset (row ID), an UUID of a storage
+        is again a tuple of an offset (row ID), the NID of a storage
         node, and a cell state."""
         raise NotImplementedError
 
@@ -238,7 +238,7 @@ class DatabaseManager(object):
     def changePartitionTable(self, ptid, cell_list):
         """Change a part of a partition table. The list of cells is
         a tuple of tuples, each of which consists of an offset (row ID),
-        an UUID of a storage node, and a cell state. The Partition
+        the NID of a storage node, and a cell state. The Partition
         Table ID must be stored as well."""
         raise NotImplementedError
 
@@ -249,8 +249,8 @@ class DatabaseManager(object):
         raise NotImplementedError
 
     def dropPartitions(self, offset_list):
-        """ Drop any data of non-assigned partitions for a given UUID """
-        raise NotImplementedError('this method must be overriden')
+        """Delete all data for specified partitions"""
+        raise NotImplementedError
 
     def dropUnfinishedData(self):
         """Drop any unfinished data from a database."""
@@ -272,7 +272,7 @@ class DatabaseManager(object):
         'unreferenced' means:
         - not in self._uncommitted_data
         - and not referenced by a fully-committed object (storage should have
-          an index or a refcound of all data ids of all objects)
+          an index or a refcount of all data ids of all objects)
         """
         raise NotImplementedError
 

neo/storage/database/mysqldb.py

@@ -152,9 +152,9 @@ class MySQLDatabaseManager(DatabaseManager):
         # The table "pt" stores a partition table.
         q("""CREATE TABLE IF NOT EXISTS pt (
                  rid INT UNSIGNED NOT NULL,
-                 uuid INT NOT NULL,
+                 nid INT NOT NULL,
                  state TINYINT UNSIGNED NOT NULL,
-                 PRIMARY KEY (rid, uuid)
+                 PRIMARY KEY (rid, nid)
              ) ENGINE = InnoDB""")
 
         p = self._use_partition and """ PARTITION BY LIST (partition) (
@@ -323,17 +323,17 @@ class MySQLDatabaseManager(DatabaseManager):
         q = self.query
         if reset:
             q("TRUNCATE pt")
-        for offset, uuid, state in cell_list:
+        for offset, nid, state in cell_list:
             # TODO: this logic should move out of database manager
             # add 'dropCells(cell_list)' to API and use one query
             if state == CellStates.DISCARDED:
-                q("DELETE FROM pt WHERE rid = %d AND uuid = %d"
-                  % (offset, uuid))
+                q("DELETE FROM pt WHERE rid = %d AND nid = %d"
+                  % (offset, nid))
             else:
                 offset_list.append(offset)
                 q("INSERT INTO pt VALUES (%d, %d, %d)"
                   " ON DUPLICATE KEY UPDATE state = %d"
-                  % (offset, uuid, state, state))
+                  % (offset, nid, state, state))
         self.setPTID(ptid)
         if self._use_partition:
             for offset in offset_list:

neo/storage/database/sqlite.py

@@ -112,9 +112,9 @@ class SQLiteDatabaseManager(DatabaseManager):
         # The table "pt" stores a partition table.
         q("""CREATE TABLE IF NOT EXISTS pt (
                  rid INTEGER NOT NULL,
-                 uuid INTEGER NOT NULL,
+                 nid INTEGER NOT NULL,
                  state INTEGER NOT NULL,
-                 PRIMARY KEY (rid, uuid))
+                 PRIMARY KEY (rid, nid))
           """)
 
         # The table "trans" stores information on committed transactions.
@@ -277,17 +277,17 @@ class SQLiteDatabaseManager(DatabaseManager):
         q = self.query
         if reset:
             q("DELETE FROM pt")
-        for offset, uuid, state in cell_list:
+        for offset, nid, state in cell_list:
             # TODO: this logic should move out of database manager
             # add 'dropCells(cell_list)' to API and use one query
             # WKRD: Why does SQLite need a statement journal file
             #       whereas we try to replace only 1 value ?
             #       We don't want to remove the 'NOT NULL' constraint
             #       so we must simulate a "REPLACE OR FAIL".
-            q("DELETE FROM pt WHERE rid=? AND uuid=?", (offset, uuid))
+            q("DELETE FROM pt WHERE rid=? AND nid=?", (offset, nid))
             if state != CellStates.DISCARDED:
                 q("INSERT OR FAIL INTO pt VALUES (?,?,?)",
-                  (offset, uuid, int(state)))
+                  (offset, nid, int(state)))
         self.setPTID(ptid)
 
     def changePartitionTable(self, ptid, cell_list):