#1059 virtual: replace qmp polling for event listening

Polling for a qmp port availability is undesirable, as QEMU only handles
one connection to the qmp port at a time, ogClient may interfere with
cloneer-manager.

Check vm thread now connects to a separate qmp tcp socket, listening for
a shutdown guest event.

When ogClient is run just after ogVDI installation (before guest
installation) it will try to connect until it's possible, ie: after an
iso is specified and a qemu vm is started that exposes the appropiate
qmp tcp port.

1 files changed, 53 insertions, 0 deletions

diff --git a/src/virtual/poweroffd.py b/src/virtual/poweroffd.py
new file mode 100644
index 0000000..63d08e1
--- /dev/null
+++ b/src/virtual/poweroffd.py
@@ -0,0 +1,53 @@
+#
+# Copyright (C) 2021 Soleta Networks <info@soleta.eu>
+#
+# This program is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Affero General Public License as published by the
+# Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+
+
+from src.virtual.qmp import QEMUMonitorProtocol
+from src.virtual.qmp import QMPCapabilitiesError, QMPConnectError
+
+QMP_DEFAULT_PORT = 4445
+QMP_DEFAULT_HOST = "127.0.0.1"
+
+def is_shutdown_event(qmp_ev):
+    """
+    """
+    return qmp_ev.get('event') == 'SHUTDOWN'
+
+
+def init(host=QMP_DEFAULT_HOST, port=QMP_DEFAULT_PORT):
+    """
+    """
+    qmpconn = QEMUMonitorProtocol((host, port))
+    try:
+        qmpconn.connect()
+    except ConnectionRefusedError:
+        print("Critical err: Connection refused")
+        return None
+    except QMPCapabilitiesError as e:
+        print("Error negotiating capabilities")
+        return None
+    return qmpconn
+
+
+def run(qmpconn):
+    """
+    """
+    while(True):
+        try:
+            qmp_ev = qmpconn.pull_event(wait=True)
+        except QMPConnectError as e:
+            print("Error trying to pull an event")
+            ret = -1
+            break
+        if is_shutdown_event(qmp_ev):
+            print("Detected guest shutdown, let's go")
+            ret = 0
+            break
+
+    qmpconn.close()
+    return ret