text: # Copyright 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
  #
  # Licensed under the Apache License, Version 2.0 (the "License"). You
  # may not use this file except in compliance with the License. A copy of
  # the License is located at
  #
  # http://aws.amazon.com/apache2.0/
  #
  # or in the "license" file accompanying this file. This file 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 os
  import sys
  import logging
  
  from botocore.history import get_global_history_recorder
  from botocore.exceptions import ProfileNotFound
  
  from awscli.compat import sqlite3
  from awscli.customizations.commands import BasicCommand
  from awscli.customizations.history.constants import HISTORY_FILENAME_ENV_VAR
  from awscli.customizations.history.constants import DEFAULT_HISTORY_FILENAME
  from awscli.customizations.history.db import DatabaseConnection
  from awscli.customizations.history.db import DatabaseRecordWriter
  from awscli.customizations.history.db import RecordBuilder
  from awscli.customizations.history.db import DatabaseHistoryHandler
  from awscli.customizations.history.show import ShowCommand
  from awscli.customizations.history.list import ListCommand
  
  
  LOG = logging.getLogger(__name__)
  HISTORY_RECORDER = get_global_history_recorder()
  
  
  def register_history_mode(event_handlers):
      event_handlers.register(
          'session-initialized', attach_history_handler)
  
  
  def register_history_commands(event_handlers):
      event_handlers.register(
          "building-command-table.main", add_history_commands)
  
  
  def attach_history_handler(session, parsed_args, **kwargs):
      if _should_enable_cli_history(session, parsed_args):
          LOG.debug('Enabling CLI history')
  
          history_filename = os.environ.get(
              HISTORY_FILENAME_ENV_VAR, DEFAULT_HISTORY_FILENAME)
          if not os.path.isdir(os.path.dirname(history_filename)):
              os.makedirs(os.path.dirname(history_filename))
  
          connection = DatabaseConnection(history_filename)
          writer = DatabaseRecordWriter(connection)
          record_builder = RecordBuilder()
          db_handler = DatabaseHistoryHandler(writer, record_builder)
  
          HISTORY_RECORDER.add_handler(db_handler)
          HISTORY_RECORDER.enable()
  
  
  def _should_enable_cli_history(session, parsed_args):
      if parsed_args.command == 'history':
          return False
      try:
          scoped_config = session.get_scoped_config()
      except ProfileNotFound:
          # If the profile does not exist, cli history is definitely not
          # enabled, but don't let the error get propogated as commands down
          # the road may handle this such as the configure set command with
          # a --profile flag set.
          return False
      has_history_enabled = scoped_config.get('cli_history') == 'enabled'
      if has_history_enabled and sqlite3 is None:
          if has_history_enabled:
              sys.stderr.write(
                  'cli_history is enabled but sqlite3 is unavailable. '
                  'Unable to collect CLI history.\n'
              )
          return False
      return has_history_enabled
  
  
  def add_history_commands(command_table, session, **kwargs):
      command_table['history'] = HistoryCommand(session)
  
  
  class HistoryCommand(BasicCommand):
      NAME = 'history'
      DESCRIPTION = (
          'Commands to interact with the history of AWS CLI commands ran '
          'over time. To record the history of AWS CLI commands set '
          '``cli_history`` to ``enabled`` in the ``~/.aws/config`` file. '
          'This can be done by running:\n\n'
          '``$ aws configure set cli_history enabled``'
      )
      SUBCOMMANDS = [
          {'name': 'show', 'command_class': ShowCommand},
          {'name': 'list', 'command_class': ListCommand}
      ]
  
      def _run_main(self, parsed_args, parsed_globals):
          if parsed_args.subcommand is None:
              raise ValueError("usage: aws [options] <command> <subcommand> "
                               "[parameters]\naws: error: too few arguments")
  