From 50891f235e480070b015e047a13e6adb61f52ecf Mon Sep 17 00:00:00 2001
From: Jarrod Johnson <jbjohnso@us.ibm.com>
Date: Sat, 1 Feb 2014 18:49:36 -0500
Subject: [PATCH] Implement session loss recovery

When a console object reports disconnect, have mechanism to get back in.
---
 confluent/consoleserver.py         | 20 ++++++++++++++++++--
 confluent/interface/console.py     | 12 ++++++++++++
 plugins/hardwaremanagement/ipmi.py | 14 +++++++++++---
 3 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/confluent/consoleserver.py b/confluent/consoleserver.py
index 399ddb5a..0f6c9192 100644
--- a/confluent/consoleserver.py
+++ b/confluent/consoleserver.py
@@ -7,6 +7,7 @@
 
 #we track nodes that are actively being logged, watched, or have attached
 #there should be no more than one handler per node
+import confluent.interface.console as conapi
 import confluent.pluginapi as plugin
 import confluent.util as util
 import eventlet
@@ -17,9 +18,15 @@ _handled_consoles = {}
 class _ConsoleHandler(object):
     def __init__(self, node, configmanager):
         self.rcpts = {}
-        self._console = plugin.handle_path("/node/%s/_console/session" % node,
-            "create", configmanager)
+        self.cfgmgr = configmanager
+        self.node = node
         self.buffer = bytearray()
+        self._connect()
+
+    def _connect(self):
+        self._console = plugin.handle_path(
+            "/node/%s/_console/session" % self.node,
+            "create", self.cfgmgr)
         self._console.connect(self.get_console_output)
 
     def unregister_rcpt(self, handle):
@@ -44,6 +51,15 @@ class _ConsoleHandler(object):
         #also, timestamp data...
 
     def get_console_output(self, data):
+        # Spawn as a greenthread, return control as soon as possible
+        # to the console object
+        eventlet.spawn(self._handle_console_output, data)
+
+    def _handle_console_output(self, data):
+        if type(data) == int:
+            if data == conapi.ConsoleEvent.Disconnect:
+                self._connect()
+            return
         self.buffer += data
         #TODO: analyze buffer for registered events, examples:
         #   panics
diff --git a/confluent/interface/console.py b/confluent/interface/console.py
index 97410041..074a31de 100644
--- a/confluent/interface/console.py
+++ b/confluent/interface/console.py
@@ -21,3 +21,15 @@ class Console(object):
     def wait_for_data(self, timeout=600):
         raise NotImplementedException("Subclassing required")
 
+    def ping(self):
+        """This function is a hint to the console plugin that now would be a
+        nice time to assess health of console connection.  Plugins that see
+        a use for this should be periodically doing this on their own for
+        logging and such, this provides a hint that a user has taken an
+        explicit interest in the console output.  In my experience, this
+        correlates with some conditions that may suggest a loss of console
+        as well, so consoles can schedule a health check to run at this time.
+        No return is expected, any error condition can be reported by sending
+        ConsoleEvent.Disconnect, just like normal."""
+        pass
+
diff --git a/plugins/hardwaremanagement/ipmi.py b/plugins/hardwaremanagement/ipmi.py
index 9aa1198f..3d416d6f 100644
--- a/plugins/hardwaremanagement/ipmi.py
+++ b/plugins/hardwaremanagement/ipmi.py
@@ -1,5 +1,5 @@
 import collections
-import confluent.interface.console
+import confluent.interface.console as conapi
 import confluent.messages as msg
 import eventlet
 import eventlet.event
@@ -107,10 +107,11 @@ def get_conn_params(node, configdata):
     }
 
 
-class IpmiConsole(confluent.interface.console.Console):
+class IpmiConsole(conapi.Console):
     def __init__(self, node, config):
         crypt = config.decrypt
         config.decrypt = True
+        self.broken = False
         configdata = config.get_node_attributes([node],
             ['secret.ipmiuser', 'secret.ipmipassphrase',
              'secret.managementuser', 'secret.managementpassphrase',
@@ -125,7 +126,12 @@ class IpmiConsole(confluent.interface.console.Console):
 
     def handle_data(self, data):
         if type(data) == dict:
-            #TODO: convert dict into a confluent.interface.console.ConsoleEvent
+            disconnect = frozenset(('Session Disconnected', 'timeout'))
+            if 'error' in data and data['error'] in disconnect:
+                self.broken = True
+                self.datacallback(conapi.ConsoleEvent.Disconnect)
+            else:
+                raise Exception("Unrecognized pyghmi input %s" % repr(data))
         else:
             self.datacallback(data)
 
@@ -156,6 +162,8 @@ class IpmiConsole(confluent.interface.console.Console):
 
     def write(self, data):
         global chainpulled
+        while self.solconnection is None and not self.broken:
+            wait_on_ipmi()
         ipmiq.append((self.solconnection.send_data, (data,)))
         if not chainpulled:
             chainpulled = True