Settings storage changed from JSON to SQLite since configurator can d…

…elete task same time daemon will update last index for it. SQLite will correctly handle concurrency issues.

common.py

@@ -1,6 +1,9 @@
 #!/usr/bin/env python
 # coding:utf-8 vi:et:ts=2
 
+import os
+
 COMM_PORT = 17963
 COMM_ADDR = 'http://localhost:{0}/'.format( COMM_PORT )
+FILE_CFG = os.path.expanduser( "~/.parabridge" )
 

parabridge.py

@@ -46,28 +46,18 @@ def status( i_oArgs ) :
     print( "Daemon is not running." )
 
 def task_add( i_oArgs ) :
-  for mTask in Settings.get( 'tasks' ) :
-    if i_oArgs.task_name == mTask[ 'name' ] :
-      logging.warning( "Already has '{0}' task".format( i_oArgs.task_name ) )
-      return
-  mTask = {
-    'name' : i_oArgs.task_name,
-    'src' : i_oArgs.task_src,
-    'dst' : i_oArgs.task_dst
-  }
-  Settings.set( 'tasks', Settings.get( 'tasks' ) + [ mTask ] )
+  sName = i_oArgs.task_name
+  sSrc = i_oArgs.task_src
+  sDst = i_oArgs.task_dst
+  if not Settings.taskAdd( sName, sSrc, sDst ) :
+    logging.warning( "Already has '{0}' task".format( sName ) )
 
 def task_del( i_oArgs ) :
-  lTasks = Settings.get( 'tasks' )
-  for mTask in lTasks :
-    if i_oArgs.task_name == mTask[ 'name' ] :
-      lTasks.remove( mTask )
-      Settings.set( 'tasks', lTasks )
-      return
-  logging.warning( "No task named '{0}'".format( i_oArgs.task_name ) )
+  if not Settings.taskDelByName( i_oArgs.task_name ) :
+    logging.warning( "No task named '{0}'".format( i_oArgs.task_name ) )
 
 def task_list( i_oArgs ) :
-  lTasks = Settings.get( 'tasks' )
+  lTasks = Settings.taskList()
   if 0 == len( lTasks ) :
     print( "Tasks list is empty." )
     return

settings.py

@@ -5,38 +5,74 @@
 import json
 import xmlrpclib
 import socket
+import sqlite3
+import uuid
 from common import *
 
+SQL_CREATE = """CREATE TABLE IF NOT EXISTS task (
+  guid TEXT,
+  name TEXT UNIQUE,
+  src TEXT,
+  dst TEXT,
+  index_last INTEGER)"""
+SQL_TASK_ADD = """INSERT INTO task (guid, name, src, dst, index_last)
+  VALUES (:guid, :name, :src, :dst, :index_last)"""
+SQL_TASK_LIST = """SELECT * FROM task"""
+SQL_TASK_DEL_BY_NAME = """DELETE FROM task WHERE name = :name"""
+
 class Settings( object ) :
 
-  m_mItems = { 'tasks' : [] }
-  sPath = os.path.expanduser( "~/.parabridge" )
-  if os.path.exists( sPath ) :
-    m_mItems.update( json.load( open( sPath ) ) )
   m_fInit = False
   m_fNotify = False
 
   @classmethod
   def init( self, notify = False ) :
     self.m_fNotify = notify
     self.m_fInit = True
+    with sqlite3.connect( FILE_CFG ) as oConn :
+      oConn.execute( SQL_CREATE )
+
+  ##  Notify daemon process so it can read updated settings.
+  @classmethod
+  def notifyIfNeeded( self ) :
+    if not self.m_fNotify : return
+    try :
+      xmlrpclib.ServerProxy( COMM_ADDR ).cfg_changed()
+    except socket.error :
+      pass
 
   @classmethod
-  def set( self, i_sName, i_uVal ) :
-    if not m_fInit : raise Exception( "Init not called." )
-    self.m_mItems[ i_sName ] = i_uVal
-    sPath = os.path.expanduser( "~/.parabridge" )
-    json.dump( self.m_mItems, open( sPath, 'w' ) )
-    ##  Notify daemon process so it can read updated settings.
-    if m_fNotify :
+  def taskAdd( self, i_sName, i_sSrc, i_sDst ) :
+    with sqlite3.connect( FILE_CFG ) as oConn :
       try :
-        oSrv = xmlrpclib.ServerProxy( COMM_ADDR )
-        oSrv.cfg_changed()
-      except socket.error :
-        pass
+        mValues = {
+          'guid' : str( uuid.uuid4() ),
+          'name' : i_sName,
+          'src' : i_sSrc,
+          'dst' : i_sDst,
+          'index_last' : 0 }
+        oConn.execute( SQL_TASK_ADD, mValues )
+      except sqlite3.IntegrityError :
+        ##  Name not unique.
+        return False
+      else :
+        return True
+      finally :
+        self.notifyIfNeeded()
 
   @classmethod
-  def get( self, i_sName ) :
-    if not m_fInit : raise Exception( "Init not called." )
-    return self.m_mItems[ i_sName ]
+  def taskDelByName( self, i_sName ) :
+    with sqlite3.connect( FILE_CFG ) as oConn :
+      oRet = oConn.execute( SQL_TASK_DEL_BY_NAME, { 'name' : i_sName } )
+      self.notifyIfNeeded()
+      return 1 == oRet.rowcount
+
+  @classmethod
+  def taskList( self ) :
+    with sqlite3.connect( FILE_CFG ) as oConn :
+      try :
+        oConn.row_factory = sqlite3.Row
+        return oConn.execute( SQL_TASK_LIST ).fetchall()
+      finally :
+        self.notifyIfNeeded()