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 POLLING_TIME_INTERVAL = 5
  34 MAX_DELETE_ATTEMPTS = 3
  35
  36 def _show_detailed_status(old_detailed_status, new_detailed_status):
  37     if new_detailed_status is not None and new_detailed_status != old_detailed_status:
  38         sys.stderr.write("detailed-status: {}\n".format(new_detailed_status))
  39         return new_detailed_status
  40     else:
  41         return old_detailed_status
  42
  43 def _get_finished_states(entity):
  44     # Note that the member name is either:
  45     # 'operationState' (NS, NSI)
  46     # '_admin.'operationalState' (VIM, WIM, SDN)
  47     # For NS and NSI, 'operationState' may be one of:
  48     # PROCESSING, COMPLETED,PARTIALLY_COMPLETED, FAILED_TEMP,FAILED,ROLLING_BACK,ROLLED_BACK
  49     # For VIM, WIM, SDN: '_admin.operationalState' may be one of:
  50     # operationalState: ENABLED, DISABLED, ERROR, PROCESSING
  51     if entity == 'NS' or entity == 'NSI':
  52         return ['COMPLETED', 'PARTIALLY_COMPLETED', 'FAILED_TEMP', 'FAILED']
  53     else:
  54         return ['ENABLED', 'ERROR']
  55
  56 def _get_operational_state(resp, entity):
  57     # Note that the member name is either:
  58     # 'operationState' (NS)
  59     # 'operational-status' (NSI)
  60     # '_admin.'operationalState' (other)
  61     if entity == 'NS' or entity == 'NSI':
  62         return resp.get('operationState')
  63     else:
  64         return resp.get('_admin', {}).get('operationalState')
  65
  66 def _op_has_finished(resp, entity):
  67     # This function returns:
  68     # 0 on success (operation has finished)
  69     # 1 on pending (operation has not finished)
  70     # -1 on error (bad response)
  71     #
  72     finished_states = _get_finished_states(entity)
  73     if resp:
  74         operationalState = _get_operational_state(resp, entity)
  75         if operationalState:
  76             if operationalState in finished_states:
  77                 return 0
  78             return 1
  79     return -1
  80
  81 def _get_detailed_status(resp, entity, detailed_status_deleted):
  82     if detailed_status_deleted:
  83         return detailed_status_deleted
  84     if entity == 'NS' or entity == 'NSI':
  85         # For NS and NSI, 'detailed-status' is a JSON "root" member:
  86         return resp.get('detailed-status')
  87     else:
  88         # For VIM, WIM, SDN, 'detailed-status' is either:
  89         # - a leaf node to '_admin' (operations NOT supported)
  90         # - a leaf node of the Nth element in the list '_admin.operations[]' (operations supported by LCM and NBI)
  91         # https://osm.etsi.org/gerrit/#/c/7767 : LCM support for operations
  92         # https://osm.etsi.org/gerrit/#/c/7734 : NBI support for current_operation
  93         ops = resp.get('_admin', {}).get('operations')
  94         op_index = resp.get('_admin', {}).get('current_operation')
  95         if ops and op_index:
  96             # Operations are supported, verify operation index
  97             if isinstance(op_index, (int)) or op_index.isdigit():
  98                 op_index = int(op_index)
  99                 if op_index > 0 and op_index < len(ops) and ops[op_index] and ops[op_index]["detailed-status"]:
 100                     return ops[op_index]["detailed-status"]
 101             # operation index is either non-numeric or out-of-range
 102             return 'Unexpected error when getting detailed-status!'
 103         else:
 104             # Operations are NOT supported
 105             return resp.get('_admin', {}).get('detailed-status')
 106
 107 def _has_delete_error(resp, entity, deleteFlag, delete_attempts_left):
 108     if deleteFlag and delete_attempts_left:
 109         state = _get_operational_state(resp, entity)
 110         if state and state == 'ERROR':
 111             return True
 112     return False
 113
 114 def wait_for_status(entity_label, entity_id, timeout, apiUrlStatus, http_cmd, deleteFlag=False):
 115     # Arguments:
 116     # entity_label: String describing the entities using '--wait':
 117     # 'NS', 'NSI', 'SDNC', 'VIM', 'WIM'
 118     # entity_id: The ID for an existing entity, the operation ID for an entity to create.
 119     # timeout: See section at top of this file for each value of TIMEOUT_<ENTITY>_OPERATION
 120     # apiUrlStatus: The endpoint to get the Response including 'detailed-status'
 121     # http_cmd: callback to HTTP command.
 122     # Passing this callback as an argument avoids importing the 'http' module here.
 123
 124     # Loop here until the operation finishes, or a timeout occurs.
 125     time_left = timeout
 126     detailed_status = None
 127     detailed_status_deleted = None
 128     time_to_return = False
 129     delete_attempts_left = MAX_DELETE_ATTEMPTS
 130     wait_for_404 = False
 131     try:
 132         while True:
 133             http_code, resp_unicode = http_cmd('{}/{}'.format(apiUrlStatus, entity_id))
 134             resp = ''
 135             if resp_unicode:
 136                 resp = json.loads(resp_unicode)
 137             # print('HTTP CODE: {}'.format(http_code))
 138             # print('RESP: {}'.format(resp))
 139             # print('URL: {}/{}'.format(apiUrlStatus, entity_id))
 140             if deleteFlag and http_code == 404:
 141                 # In case of deletion, '404 Not Found' means successfully deleted
 142                 # Display 'detailed-status: Deleted' and return
 143                 time_to_return = True
 144                 detailed_status_deleted = 'Deleted'
 145             elif deleteFlag and http_code in (200, 201, 202, 204):
 146                 # In case of deletion and HTTP Status = 20* OK, deletion may be PROCESSING or COMPLETED
 147                 # If this is the case, we should keep on polling until 404 (deleted) is returned.
 148                 wait_for_404 = True
 149             elif http_code not in (200, 201, 202, 204):
 150                 raise ClientException(str(resp))
 151             if not time_to_return:
 152                 # Get operation status
 153                 op_status = _op_has_finished(resp, entity_label)
 154                 if op_status == -1:
 155                     # An error occurred
 156                     raise ClientException('unexpected response from server - {} '.format(
 157                         str(resp)))
 158                 elif op_status == 0:
 159                     # If there was an error upon deletion, try again to delete the same instance
 160                     # If the error is the same, there is probably nothing we can do but exit with error.
 161                     # If the error is different (i.e. 404), the instance was probably already corrupt, that is,
 162                     # operation(al)State was probably ERROR before deletion.
 163                     # In such a case, even if the previous state was ERROR, the deletion was successful,
 164                     # so detailed-status should be set to Deleted.
 165                     if _has_delete_error(resp, entity_label, deleteFlag, delete_attempts_left):
 166                         delete_attempts_left -= 1
 167                     else:
 168                         # Operation has finished, either with success or error
 169                         if deleteFlag:
 170                             delete_attempts_left -= 1
 171                             if not wait_for_404 and delete_attempts_left < MAX_DELETE_ATTEMPTS:
 172                                 time_to_return = True
 173                         else:
 174                             time_to_return = True
 175             new_detailed_status = _get_detailed_status(resp, entity_label, detailed_status_deleted)
 176             # print('DETAILED-STATUS: {}'.format(new_detailed_status))
 177             # print('DELETE-ATTEMPTS-LEFT: {}'.format(delete_attempts_left))
 178             if not new_detailed_status:
 179                 new_detailed_status = 'In progress'
 180             # TODO: Change LCM to provide detailed-status more up to date
 181             # At the moment of this writing, 'detailed-status' may return different strings
 182             # from different resources:
 183             # /nslcm/v1/ns_lcm_op_occs/<id>       ---> ''
 184             # /nslcm/v1/ns_instances_content/<id> ---> 'deleting charms'
 185             detailed_status = _show_detailed_status(detailed_status, new_detailed_status)
 186             if time_to_return:
 187                 return
 188             time_left -= POLLING_TIME_INTERVAL
 189             sleep(POLLING_TIME_INTERVAL)
 190             if time_left <= 0:
 191                 # There was a timeout, so raise an exception
 192                 raise ClientException('operation timeout, waited for {} seconds'.format(timeout))
 193     except ClientException as exc:
 194         message="Operation failed for {}:\nerror:\n{}".format(
 195             entity_label,
 196             str(exc))
 197         raise ClientException(message)