updates

slapos/qemuqmpclient/__init__.py

@@ -69,13 +69,20 @@ def getInitialQemuResourceDict(pid_file):
     return None
 
   with open(pid_file) as f:
+    try:
       pid = int(f.read())
+    except ValueError, e:
+      raise ValueError("%r is empty or doesn't contain a valid pid number: %s" % (
+        pid_file, str(e)))
 
   try:
     process = psutil.Process(pid)
   except psutil.NoSuchProcess:
-    print 'No process with pid %s' % pid
-    return None
+    raise ValueError('No process with pid %s' % pid)
+
+  if not process.name().startswith('qemu-system'):
+    raise ValueError("The pid %s is used by %r and not a qemu process." % (
+      pid, process.name()))
   resource_dict = {'cpu': None, 'ram': None}
   cmd_list = process.cmdline()
   cpu_index = cmd_list.index('-smp')
@@ -137,7 +144,10 @@ class QemuQMPWrapper(object):
       data = self.sockf.readline()
       if not data:
         return
+      try:
         response = json.loads(data)
+      except ValueError:
+        raise ValueError('Wrong data: %s' % data)
       if 'error' in response:
         raise QmpCommandError(response["error"]["desc"])
       if 'event' in response:
@@ -148,18 +158,17 @@ class QemuQMPWrapper(object):
 
       return response
 
-  def _send(self, message):
+  def _send(self, message, retry=0, sleep=0.5):
     self.socket.sendall(json.dumps(message))
-    return self._readResponse()
-
-  def _sendRetry(self, message):
-    """
-      Send Qmp message and retry once if the result is None
-    """
-    result = self._send(message)
-    if result is None:
-      return self._send(message)
-    return result
+    response = self._readResponse()
+    for i in range(0, retry):
+      if response is not None:
+        break
+      print "Retrying send command after %s second(s)..." % sleep
+      time.sleep(sleep)
+      self.socket.sendall(json.dumps(message))
+      response = self._readResponse()
+    return response
 
   def _getVMStatus(self):
     response = self._send({'execute': 'query-status'})
@@ -317,9 +326,9 @@ class QemuQMPWrapper(object):
       return some info about VM CPUs
     """
     cpu_info_dict = {'hotplugged': [], 'base': []}
-    cpu_list = self._sendRetry({
+    cpu_list = self._send({
       'execute': 'query-cpus'
-    })['return']
+    }, retry=5)['return']
     for cpu in cpu_list:
       if 'unattached' in cpu['qom_path']:
         index = 'base'
@@ -337,9 +346,9 @@ class QemuQMPWrapper(object):
       return some info about VM Memory. Can only say info about hotplugged RAM
     """
     mem_info_dict = {'hotplugged': [], 'base': []}
-    memory_list = self._sendRetry({
+    memory_list = self._send({
       'execute': 'query-memory-devices'
-    })['return']
+    }, retry=5)['return']
     for mem in memory_list:
       if mem['data']['hotplugged'] == True:
         mem_info_dict['hotplugged'].append(mem['data'])
@@ -386,6 +395,7 @@ class QemuQMPWrapper(object):
       raise ValueError("Cannot remove device %s" % dev_id)
 
     # try soft reboot of the VM
+    print "Powering down the VM..."
     self.powerdown()
     system_exited = False
     # wait for ~10 seconds if the system exit, else quit Qemu
@@ -418,7 +428,7 @@ class QemuQMPWrapper(object):
     unremovable_cpu = 0
     cpu_hotplugable_list = self._send({
       'execute': 'query-hotpluggable-cpus'
-    })['return']
+    }, retry=5)['return']
     cpu_hotplugable_list.reverse()
     for cpu in cpu_hotplugable_list:
       if cpu.get('qom-path', '') == '':
@@ -508,8 +518,8 @@ class QemuQMPWrapper(object):
     num_slot_used = 0
     memory_id_list = [] # current hotplugged memory
     cleanup_memdev_id_dict = {}
-    current_dimm_list = self._send({ "execute": "query-memory-devices" })
-    current_memdev_list = self._send({ "execute": "query-memdev" })
+    current_dimm_list = self._send({ "execute": "query-memory-devices" }, retry=5)
+    current_memdev_list = self._send({ "execute": "query-memdev" }, retry=5)
 
     for memdev in current_memdev_list['return']:
       cleanup_memdev_id_dict[memdev['id']] = ''

slapos/test/test_qemuqmpclient.py

@@ -76,7 +76,7 @@ class TestQemuQMPWrapper(unittest.TestCase):
       if message['arguments']['id'].startswith('cpu'):
         self.setChange('cpu', -1)
     if self.fail:
-      return {"error": {"class": "CommandFailed", "message": ""}}
+      return {"error": {"class": "CommandFailed", "desc": ""}}
     return {"return": {}}
 
   def fake_getEventList(self, timeout=0, cleanup=False):