[lnst] SlavePool: test connection to slave machines

[Jiří Pírko]

commit 0deed16ab3a1edea3c8664e311cbacaf8d4f3055
Author: Ondrej Lichtner <olichtne(a)redhat.com&gt;
Date:   Fri Apr 5 16:19:55 2013 +0200

    SlavePool: test connection to slave machines
    
    This commit adds a new functionality to the SlavePool class. Until now
    we have used all configuration files located in the pool directory and
    used them in our matching algorithm. This however won't work correctly
    if some machines are turned off. In this case the matching algorithm
    uses the first configuration that matches even if it contains a machine
    that is turned off which will result in a failure state. Even though
    there exists a match that is fully available.
    
    This commit adds code to the SlavePool initialization where we test
    connectability of each machine being added to the pool and skip machines
    that are turned off.
    
    Signed-off-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;

 lnst/Controller/NetTestController.py |    2 +-
 lnst/Controller/SlavePool.py         |   16 +++++++++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)
---
diff --git a/lnst/Controller/NetTestController.py b/lnst/Controller/NetTestController.py
index 645ed78..ffa2bf8 100644
--- a/lnst/Controller/NetTestController.py
+++ b/lnst/Controller/NetTestController.py
@@ -51,7 +51,7 @@ class NetTestController:
         self._msg_dispatcher = MessageDispatcher()
 
         sp = SlavePool(config.get_option('environment', 'pool_dirs'),
-                       check_process_running("libvirtd"))
+                       check_process_running("libvirtd"), config)
         self._slave_pool = sp
 
         self._recipe = recipe = {}
diff --git a/lnst/Controller/SlavePool.py b/lnst/Controller/SlavePool.py
index 8470190..c98bb24 100644
--- a/lnst/Controller/SlavePool.py
+++ b/lnst/Controller/SlavePool.py
@@ -19,6 +19,7 @@ import re
 import copy
 from xml.dom import minidom
 from lnst.Common.XmlProcessing import XmlDomTreeInit
+from lnst.Common.NetUtils import test_tcp_connection
 from lnst.Controller.NetTestParse import SlaveMachineParse
 
 class SlavePool:
@@ -35,7 +36,8 @@ class SlavePool:
 
     _allow_virtual = False
 
-    def __init__(self, pool_dirs, allow_virtual=False):
+    def __init__(self, pool_dirs, allow_virtual=False, config=None):
+        self._config = config
         self._allow_virtual = allow_virtual
         for pool_dir in pool_dirs:
             self.add_dir(pool_dir)
@@ -64,8 +66,20 @@ class SlavePool:
             slavemachine = dom.getElementsByTagName("slavemachine")[0]
 
             parser.parse(slavemachine)
+
+            hostname = machine["params"]["hostname"]
+            if "rpcport" in machine:
+                port = machine["params"]["rpcport"]
+            else:
+                port = self._config.get_option('environment', 'rpcport')
+            logging.info("Querying slave machine %s." % machine_id)
+            if not test_tcp_connection(hostname, port):
+                return
+
             if 'libvirt_domain' not in machine['params'] \
                                    or self._allow_virtual:
+                logging.info("Adding slave machine %s to slave pool."
+                                    % machine_id)
                 self._pool[machine_id] = machine
             else:
                 logging.warning("libvirtd not found- Machine Pool skipping "\