ovsdb-idl: Change interface to conditional monitoring.

Most users of OVSDB react to whatever is currently in their view of the
database, as opposed to keeping track of changes and reacting to those
changes individually.  The interface to conditional monitoring was
different, in that it expected the client to say what to add or remove from
monitoring instead of what to monitor.  This seemed reasonable at the time,
but in practice it turns out that the usual approach actually works better,
because the condition is generally a function of the data visible in the
database.  This commit changes the approach.

This commit also changes the meaning of an empty condition for a table.
Previously, an empty condition meant to replicate every row.  Now, an empty
condition means to replicate no rows.  This is more convenient for code
that gradually constructs conditions, because it does not need special
cases for replicating nothing.

This commit also changes the internal implementation of conditions from
linked lists to arrays.  I just couldn't see an advantage to using linked
lists.

Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Liran Schour <lirans@il.ibm.com>

1 files changed, 4 insertions, 12 deletions

diff --git a/tests/test-ovsdb.py b/tests/test-ovsdb.py
index 185215ae6..dced56b99 100644
--- a/tests/test-ovsdb.py
+++ b/tests/test-ovsdb.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
+# Copyright (c) 2009, 2010, 2011, 2012, 2016 Nicira, Inc.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -531,25 +531,17 @@ def idl_set(idl, commands, step):
 
 
 def update_condition(idl, commands):
-    commands = commands.split(";")
+    commands = commands[len("condition "):].split(";")
     for command in commands:
-        command = command[len("condition "):]
-        if "add" in command:
-            add_cmd = True
-            command = command[len("add "):]
-        else:
-            add_cmd = False
-            command = command[len("remove "):]
-
         command = command.split(" ")
         if(len(command) != 2):
-            sys.stderr.write("Error parsong condition %s\n" % command)
+            sys.stderr.write("Error parsing condition %s\n" % command)
             sys.exit(1)
 
         table = command[0]
         cond = ovs.json.from_string(command[1])
 
-        idl.cond_change(table, add_cmd, cond)
+        idl.cond_change(table, cond)
 
 
 def do_idl(schema_file, remote, *commands):