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 = 1
  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 and NSI)
  46     # '_admin.'operationalState' (other)
  47     # For NS and NSI, 'operationState' may be one of:
  48     # PROCESSING, COMPLETED,PARTIALLY_COMPLETED, FAILED_TEMP,FAILED,ROLLING_BACK,ROLLED_BACK
  49     # For other entities, '_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 other entities, 'detailed-status' a leaf node to '_admin':
  89         return resp.get('_admin', {}).get('detailed-status')
  90
  91 def _has_delete_error(resp, entity, deleteFlag, delete_attempts_left):
  92     if deleteFlag and delete_attempts_left:
  93         state = _get_operational_state(resp, entity)
  94         if state and state == 'ERROR':
  95             return True
  96     return False
  97
  98 def wait_for_status(entity_label, entity_id, timeout, apiUrlStatus, http_cmd, deleteFlag=False):
  99     # Arguments:
 100     # entity_label: String describing the entities using '--wait':
 101     # 'NS', 'NSI', 'SDNC', 'VIM', 'WIM'
 102     # entity_id: The ID for an existing entity, the operation ID for an entity to create.
 103     # timeout: See section at top of this file for each value of TIMEOUT_<ENTITY>_OPERATION
 104     # apiUrlStatus: The endpoint to get the Response including 'detailed-status'
 105     # http_cmd: callback to HTTP command.
 106     # Passing this callback as an argument avoids importing the 'http' module here.
 107
 108     # Loop here until the operation finishes, or a timeout occurs.
 109     time_left = timeout
 110     detailed_status = None
 111     detailed_status_deleted = None
 112     time_to_return = False
 113     delete_attempts_left = MAX_DELETE_ATTEMPTS
 114     wait_for_404 = False
 115     try:
 116         while True:
 117             http_code, resp_unicode = http_cmd('{}/{}'.format(apiUrlStatus, entity_id))
 118             resp = ''
 119             if resp_unicode:
 120                 resp = json.loads(resp_unicode)
 121             # print 'HTTP CODE: {}'.format(http_code)
 122             # print 'RESP: {}'.format(resp)
 123             # print 'URL: {}/{}'.format(apiUrlStatus, entity_id)
 124             if deleteFlag and http_code == 404:
 125                 # In case of deletion, '404 Not Found' means successfully deleted
 126                 # Display 'detailed-status: Deleted' and return
 127                 time_to_return = True
 128                 detailed_status_deleted = 'Deleted'
 129             elif deleteFlag and http_code in (200, 201, 202, 204):
 130                 # In case of deletion and HTTP Status = 20* OK, deletion may be PROCESSING or COMPLETED
 131                 # If this is the case, we should keep on polling until 404 (deleted) is returned.
 132                 wait_for_404 = True
 133             elif http_code not in (200, 201, 202, 204):
 134                 raise ClientException(str(resp))
 135             if not time_to_return:
 136                 # Get operation status
 137                 op_status = _op_has_finished(resp, entity_label)
 138                 if op_status == -1:
 139                     # An error occurred
 140                     raise ClientException('unexpected response from server - {} '.format(
 141                         str(resp)))
 142                 elif op_status == 0:
 143                     # If there was an error upon deletion, try again to delete the same instance
 144                     # If the error is the same, there is probably nothing we can do but exit with error.
 145                     # If the error is different (i.e. 404), the instance was probably already corrupt, that is,
 146                     # operation(al)State was probably ERROR before deletion.
 147                     # In such a case, even if the previous state was ERROR, the deletion was successful,
 148                     # so detailed-status should be set to Deleted.
 149                     if _has_delete_error(resp, entity_label, deleteFlag, delete_attempts_left):
 150                         delete_attempts_left -= 1
 151                     else:
 152                         # Operation has finished, either with success or error
 153                         if deleteFlag:
 154                             delete_attempts_left -= 1
 155                             if not wait_for_404 and delete_attempts_left < MAX_DELETE_ATTEMPTS:
 156                                 time_to_return = True
 157                         else:
 158                             time_to_return = True
 159             new_detailed_status = _get_detailed_status(resp, entity_label, detailed_status_deleted)
 160             # print 'DETAILED-STATUS: {}'.format(new_detailed_status)
 161             # print 'DELETE-ATTEMPTS-LEFT: {}'.format(delete_attempts_left)
 162             if not new_detailed_status:
 163                 new_detailed_status = 'In progress'
 164             # TODO: Change LCM to provide detailed-status more up to date
 165             # At the moment of this writing, 'detailed-status' may return different strings
 166             # from different resources:
 167             # /nslcm/v1/ns_lcm_op_occs/<id>       ---> ''
 168             # /nslcm/v1/ns_instances_content/<id> ---> 'deleting charms'
 169             detailed_status = _show_detailed_status(detailed_status, new_detailed_status)
 170             if time_to_return:
 171                 return
 172             time_left -= POLLING_TIME_INTERVAL
 173             sleep(POLLING_TIME_INTERVAL)
 174             if time_left <= 0:
 175                 # There was a timeout, so raise an exception
 176                 raise ClientException('operation timeout, waited for {} seconds'.format(timeout))
 177     except ClientException as exc:
 178         message="Operation failed for {}:\nerror:\n{}".format(
 179             entity_label,
 180             exc.message)
 181         raise ClientException(message)