[Users] Unable to get latest resource status

[Alex Jia]

Hi Juan,
Although I haven't try it, I think you're right, I should refresh VM
in loop body. 

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

Thanks,
Alex 


----- 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>
>