text: # Copyright 2018 - Nokia
  #
  # Licensed under the Apache License, Version 2.0 (the "License"); you may
  # not use this file except in compliance with the License. You may obtain
  # a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  # License for the specific language governing permissions and limitations
  # under the License.
  import ast
  from collections import namedtuple
  import datetime
  from oslo_log import log
  from oslo_utils import uuidutils
  from osprofiler import profiler
  import re
  from six.moves.urllib.parse import urlparse
  from vitrage.common.constants import TenantProps
  from vitrage.common.constants import VertexProperties as Vprops
  from vitrage.notifier.plugins.webhook.utils import db_row_to_dict
  from vitrage import storage
  from vitrage.storage.sqlalchemy.models import Webhooks
  
  LOG = log.getLogger(__name__)
  
  Result = namedtuple("Result", ["is_valid", "message"])
  
  
  @profiler.trace_cls("webhook apis",
                      info={}, hide_args=False, trace_private=False)
  class WebhookApis(object):
      DELETED_ROWS_SUCCESS = 1
  
      def __init__(self, conf):
          self.conf = conf
          self.db_conn = storage.get_connection_from_config(conf)
  
      def delete_webhook(self, ctx, id):
  
          LOG.info("Delete webhook with id: %s",
                   str(id))
  
          deleted_rows_count = self.db_conn.webhooks.delete(id)
  
          if deleted_rows_count == self.DELETED_ROWS_SUCCESS:
              return {'SUCCESS': 'Webhook %s deleted' % id}
          else:
              return None
  
      def get_all_webhooks(self, ctx, all_tenants):
          LOG.info("List all webhooks")
          if all_tenants and ctx.get(TenantProps.IS_ADMIN, False):
              res = self.db_conn.webhooks.query()
          else:
              res = self.db_conn.webhooks.query(project_id=ctx.get(
                  TenantProps.TENANT, ""))
          LOG.info(res)
          webhooks = [db_row_to_dict(webhook) for webhook in res]
  
          return webhooks
  
      def add_webhook(self, ctx, url, headers=None, regex_filter=None):
          res = self._check_valid_webhook(url, headers, regex_filter)
          if not res.is_valid:
              LOG.exception("Failed to create webhook: %s" % res.message)
              return res.message
          try:
              db_row = self._webhook_to_db_row(url, headers, regex_filter, ctx)
              self.db_conn.webhooks.create(db_row)
              return db_row_to_dict(db_row)
          except Exception as e:
              LOG.exception("Failed to add webhook to DB: %s", str(e))
              return {"ERROR": str(e)}
  
      def get_webhook(self, ctx, id):
          try:
              webhooks = self.db_conn.webhooks.query(id=id)
              # Check that webhook belongs to current tenant or current tenant
              #  is admin
              if len(webhooks) == 0:
                  LOG.warning("Webhook not found - %s" % id)
                  return None
              if ctx.get(TenantProps.TENANT, "") == \
                      webhooks[0][Vprops.PROJECT_ID] or ctx.get(
                      TenantProps.IS_ADMIN, False):
                  return (webhooks[0])
              else:
                  LOG.warning('Webhook show - Authorization failed (%s)',
                              id)
                  return None
          except Exception as e:
              LOG.exception("Failed to get webhook: %s", str(e))
              return {"ERROR": str(e)}
  
      def _webhook_to_db_row(self, url, headers, regex_filter, ctx):
          if not regex_filter:
              regex_filter = ""
          if not headers:
              headers = ""
          uuid = uuidutils.generate_uuid()
          project_id = ctx.get(TenantProps.TENANT, "")
          is_admin = ctx.get(TenantProps.IS_ADMIN, False)
          created_at = str(datetime.datetime.now())
          db_row = Webhooks(id=uuid,
                            project_id=project_id,
                            is_admin_webhook=is_admin,
                            created_at=created_at,
                            url=url,
                            headers=headers,
                            regex_filter=regex_filter)
          return db_row
  
      def _check_valid_webhook(self, url, headers, regex_filter):
          if not self._validate_url(url):
              return Result(False, {"ERROR": "Invalid URL"})
          elif not self._validate_headers(headers):
              return Result(False, {"ERROR": "Headers in invalid format"})
          elif not self._validate_regex(regex_filter):
              return Result(False, {"ERROR": "Invalid RegEx"})
          return Result(True, "")
  
      def _validate_url(self, url):
          try:
              result = urlparse(url)
              if not result.scheme or not result.netloc:
                  return False
          except Exception:
              return False
          return True
  
      def _validate_regex(self, regex_filter):
          if regex_filter:
              try:
                  filter_dict = ast.literal_eval(regex_filter)
                  if not isinstance(filter_dict, dict):
                      return False
                  for filter in filter_dict.values():
                      re.compile(filter)
              except Exception:
                  return False
          return True
  
      def _validate_headers(self, headers):
          if headers:
              try:
                  return isinstance(ast.literal_eval(headers), dict)
              except Exception:
                  return False
          return True
  