[Users] Unable to get latest resource status

[Juan Hernandez]

On 04/27/2012 05:27 PM, Alex Jia wrote:
> Although I haven't try it, I think you're right, I should refresh VM
> in loop body.

Let me know what is the result in your environment.

> In addition, as I said, it will be convenient if we have wait_for_status 
> function like before.

I will look into it. I would greatly appreciate if you can open a bug to
request and track it.

> ----- Original Message -----
> From: "Juan Hernandez" <juan.hernandez at redhat.com>
> To: "Alex Jia" <ajia at redhat.com>
> Cc: users at ovirt.org, "Rita Wu" <rwu at redhat.com>
> Sent: Friday, April 27, 2012 8:17:05 PM
> Subject: Re: [Users] Unable to get latest resource status
> 
> On 04/27/2012 12:06 PM, Alex Jia wrote:
>> On 04/27/2012 04:06 PM, Juan Hernandez wrote:
>>> On 04/26/2012 05:49 PM, Alex Jia wrote:
>>>> I built ovirt-engine-sdk rpm based on git repo 'http://gerrit.ovirt.org/p/ovirt-engine-sdk.git',
>>>> then the ovirt-engine-sdk works well for me, I can get resource information from Ovirt/RHEVM(3.0)
>>>> on the rhel6.2.
>>>>
>>>> The only question is I can't get latest resource status when I changed VM from 'suspended' to 'up'
>>>> status, the api.vms.get(vm_name).status.state is always 'suspended' status, I can get a correct
>>>> VM status unless I reconnect Ovirt/RHEVM, it's not convenient for users, I remember there are reload
>>>> and wait_for_status method in old python binding API of RHEV(python-rhev), the wait_for_status method
>>>> will reload resource then get current resource status, however, I haven't found similar method in
>>>> ovirt-engine-sdk.
>>> Are you sure you are calling api.vms.get(vm_name) each time? Or are you
>>> doing something like this:
>>>
>>> vm = api.vms.get(vm_name)
>>> while vm.status.state == "suspended":
>>>      sleep(10)
>> Yeah, I put 'api.vms.get(vm_name)' in a loop body like above codes.
>>> If you are doing that the vm information is retrieved only once, not
>>> each time. If this is the case try something like this:
>>>
>>> while api.vms.get(VM_NAME).status.state == "suspended":
>>>      sleep(1)
>>>
>>> Can you share that snippet of code so that I can try to reproduce it?
>> Okay, I will list my snippet of code in here, you may replace 'logging' 
>> with 'print' then remove
>> useless '()' if need. thanks.
>>
>>
>> <snip>
>> import time, logging
>> from ovirtsdk.api import API
>> from ovirtsdk.xml import params
>>
>> class RHEV(object):
>>      """
>>      RHEV class
>>      """
>>
>>      def __init__(self, url, username, password):
>>          try:
>>              self.api = API(url, username, password)
>>          except Exception as e:
>>              logging.error('could not connect: %s\n' % str(e))
>>          else:
>>              logging.info('success: RHEV manager could be reached OK\n')
>>
>>      def vm_start(self, vm_name):
>>          try:
>>              vm = self.api.vms.get(vm_name)
>>              if vm.status.state != 'up':
>>                  logging.info('Starting VM')
>>                  vm.start()
>>                  logging.info('Waiting for VM to reach Up status')
>>                  while vm.status.state != 'up':
> 
> I think that the problem is with the line above. The VM object that you
> get with "self.api.vms.get(vm_name)" is not automatically refreshed, you
> have to refresh it before each iteration calling the "api.vms.get(...)"
> method again:
> 
>   while api.vms.get(vm_name).status.state != 'up':
> 
> Can you try that?
> 
>>                      time.sleep(1)
>>              else:
>>                  logging.debug('VM already up')
>>          except Exception as e:
>>              logging.error('Failed to start VM:\n%s' % str(e))
>>
>>      def vm_suspend(self, vm_name):
>>          vm = self.api.vms.get(vm_name)
>>          while vm.status.state != 'suspended':
>>              try:
>>                  logging.info('Suspend VM')
>>                  vm.suspend()
>>                  logging.info('Waiting for VM to reach suspended status')
>>                  while vm.status.state != 'suspended':
> 
> Same here ^.
> 
>>                      time.sleep(1)
>>
>>              except Exception as e:
>>                  if e.reason == 'Bad Request' \
>>                      and 'asynchronous running tasks' in e.detail:
>>                      logging.warning('VM has asynchronous running tasks, 
>> trying again')
>>                      time.sleep(1)
>>                  else:
>>                      logging.error('Failed to suspend VM:\n%s' % str(e))
>>                      break
>>
>>      def vm_resume(self, vm_name):
>>          try:
>>              vm = self.api.vms.get(vm_name)
>>              if vm.status.state != 'up':
>>                  logging.info('Resume VM')
>>                  vm.start()
>>                  logging.info('Waiting for VM to resume')
>>                  while vm.status.state != 'up':
> 
> Same here ^.
> 
>>                      time.sleep(1)
>>              else:
>>                  logging.debug('VM already up')
>>          except Exception as e:
>>              logging.error('Failed to resume VM:\n%s' % str(e))
>>
>> </snip>
>>
>