osmclient/common/wait.py

   1 # Copyright 2019 Telefonica
   2 #
   3 # All Rights Reserved.
   4 #
   5 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
   6 #    not use this file except in compliance with the License. You may obtain
   7 #    a copy of the License at
   8 #
   9 #         http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 #    Unless required by applicable law or agreed to in writing, software
  12 #    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  13 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  14 #    License for the specific language governing permissions and limitations
  15 #    under the License.
  16
  17 """
  18 OSM API handling for the '--wait' option
  19 """
  20
  21 from osmclient.common.exceptions import ClientException
  22 import json
  23 from time import sleep
  24 import sys
  25
  26 # Declare a constant for each module, to allow customizing each timeout in the future
  27 TIMEOUT_GENERIC_OPERATION = 600
  28 TIMEOUT_NSI_OPERATION = TIMEOUT_GENERIC_OPERATION
  29 TIMEOUT_SDNC_OPERATION = TIMEOUT_GENERIC_OPERATION
  30 TIMEOUT_VIM_OPERATION = TIMEOUT_GENERIC_OPERATION
  31 TIMEOUT_WIM_OPERATION = TIMEOUT_GENERIC_OPERATION
  32 TIMEOUT_NS_OPERATION = 3600
  33
  34 POLLING_TIME_INTERVAL = 1
  35
  36 MAX_DELETE_ATTEMPTS = 3
  37
  38 def _show_detailed_status(old_detailed_status, new_detailed_status):
  39     if new_detailed_status is not None and new_detailed_status != old_detailed_status:
  40         sys.stderr.write("detailed-status: {}\n".format(new_detailed_status))
  41         return new_detailed_status
  42     else:
  43         return old_detailed_status
  44
  45 def _get_finished_states(entity):
  46     # Note that the member name is either:
  47     # 'operationState' (NS and NSI)
  48     # '_admin.'operationalState' (other)
  49     # For NS and NSI, 'operationState' may be one of:
  50     # PROCESSING, COMPLETED,PARTIALLY_COMPLETED, FAILED_TEMP,FAILED,ROLLING_BACK,ROLLED_BACK
  51     # For other entities, '_admin.operationalState' may be one of:
  52     # operationalState: ENABLED, DISABLED, ERROR, PROCESSING
  53     if entity == 'NS' or entity == 'NSI':
  54         return ['COMPLETED', 'PARTIALLY_COMPLETED', 'FAILED_TEMP', 'FAILED']
  55     else:
  56         return ['ENABLED', 'ERROR']
  57
  58 def _get_operational_state(resp, entity):
  59     # Note that the member name is either:
  60     # 'operationState' (NS)
  61     # 'operational-status' (NSI)
  62     # '_admin.'operationalState' (other)
  63     if entity == 'NS' or entity == 'NSI':
  64         return resp.get('operationState')
  65     else:
  66         return resp.get('_admin', {}).get('operationalState')
  67
  68 def _op_has_finished(resp, entity):
  69     # _op_has_finished() returns:
  70     # 0 on success (operation has finished)
  71     # 1 on pending (operation has not finished)
  72     # -1 on error (bad response)
  73     #
  74     finished_states = _get_finished_states(entity)
  75     if resp:
  76         operationalState = _get_operational_state(resp, entity)
  77         if operationalState:
  78             if operationalState in finished_states:
  79                 return 0
  80             return 1
  81     return -1
  82
  83 def _get_detailed_status(resp, entity, detailed_status_deleted):
  84     if detailed_status_deleted:
  85         return detailed_status_deleted
  86     if entity == 'NS' or entity == 'NSI':
  87         # For NS and NSI, 'detailed-status' is a JSON "root" member:
  88         return resp.get('detailed-status')
  89     else:
  90         # For other entities, 'detailed-status' a leaf node to '_admin':
  91         return resp.get('_admin', {}).get('detailed-status')
  92
  93 def _has_delete_error(resp, entity, deleteFlag, delete_attempts_left):
  94     if deleteFlag and delete_attempts_left:
  95         state = _get_operational_state(resp, entity)
  96         if state and state == 'ERROR':
  97             return True
  98     return False
  99
 100 def wait_for_status(entity_label, entity_id, timeout, apiUrlStatus, http_cmd, deleteFlag=False):
 101     # Arguments:
 102     # entity_label: String describing the entities using '--wait':
 103     # 'NS', 'NSI', 'SDNC', 'VIM', 'WIM'
 104     # entity_id: The ID for an existing entity, the operation ID for an entity to create.
 105     # timeout: See section at top of this file for each value of TIMEOUT_<ENTITY>_OPERATION
 106     # apiUrlStatus: The endpoint to get the Response including 'detailed-status'
 107     # http_cmd: callback to HTTP command.
 108     # Passing this callback as an argument avoids importing the 'http' module here.
 109
 110     # Loop here until the operation finishes, or a timeout occurs.
 111     time_left = timeout
 112     detailed_status = None
 113     detailed_status_deleted = None
 114     time_to_return = False
 115     delete_attempts_left = MAX_DELETE_ATTEMPTS
 116     try:
 117         while True:
 118             http_code, resp_unicode = http_cmd('{}/{}'.format(apiUrlStatus, entity_id))
 119             resp = ''
 120             if resp_unicode:
 121                 resp = json.loads(resp_unicode)
 122             # print 'HTTP CODE: {}'.format(http_code)
 123             # print 'RESP: {}'.format(resp)
 124             # print 'URL: {}/{}'.format(apiUrlStatus, entity_id)
 125             if deleteFlag and http_code == 404:
 126                 # In case of deletion, '404 Not Found' means successfully deleted
 127                 # Display 'detailed-status: Deleted' and return
 128                 time_to_return = True
 129                 detailed_status_deleted = 'Deleted'
 130             elif http_code not in (200, 201, 202, 204):
 131                 raise ClientException(str(resp))
 132             if not time_to_return:
 133                 # Get operation status
 134                 op_status = _op_has_finished(resp, entity_label)
 135                 if op_status == -1:
 136                     # An error occurred
 137                     raise ClientException('unexpected response from server - {} '.format(
 138                         str(resp)))
 139                 elif op_status == 0:
 140                     # If there was an error upon deletion, try again to delete the same instance
 141                     # If the error is the same, there is probably nothing we can do but exit with error.
 142                     # If the error is different (i.e. 404), the instance was probably already corrupt, that is,
 143                     # operation(al)State was probably ERROR before deletion.
 144                     # In such a case, even if the previous state was ERROR, the deletion was successful,
 145                     # so detailed-status should be set to Deleted.
 146                     if _has_delete_error(resp, entity_label, deleteFlag, delete_attempts_left):
 147                         delete_attempts_left -= 1
 148                     else:
 149                         # Operation has finished, either with success or error
 150                         if deleteFlag:
 151                             if delete_attempts_left < MAX_DELETE_ATTEMPTS:
 152                                 time_to_return = True
 153                             delete_attempts_left -= 1
 154                         else:
 155                             time_to_return = True
 156             new_detailed_status = _get_detailed_status(resp, entity_label, detailed_status_deleted)
 157             if not new_detailed_status:
 158                 new_detailed_status = 'In progress'
 159             # TODO: Change LCM to provide detailed-status more up to date
 160             # At the moment of this writing, 'detailed-status' may return different strings
 161             # from different resources:
 162             # /nslcm/v1/ns_lcm_op_occs/<id>       ---> ''
 163             # /nslcm/v1/ns_instances_content/<id> ---> 'deleting charms'
 164             detailed_status = _show_detailed_status(detailed_status, new_detailed_status)
 165             if time_to_return:
 166                 return
 167             time_left -= POLLING_TIME_INTERVAL
 168             sleep(POLLING_TIME_INTERVAL)
 169             if time_left <= 0:
 170                 # There was a timeout, so raise an exception
 171                 raise ClientException('operation timeout, waited for {} seconds'.format(timeout))
 172     except ClientException as exc:
 173         message="Operation failed for {}:\nerror:\n{}".format(
 174             entity_label,
 175             exc.message)
 176         raise ClientException(message)