2단계: 원장과의 연결을 테스트

원장과의 연결을 테스트하려면

1. 다음 프로그램(connect_to_ledger.py)을 사용하여 vehicle-registration 원장에 대한 데이터 세션 연결을 생성합니다.

   3.x

   # Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
   # SPDX-License-Identifier: MIT-0
   #
   # Permission is hereby granted, free of charge, to any person obtaining a copy of this
   # software and associated documentation files (the "Software"), to deal in the Software
   # without restriction, including without limitation the rights to use, copy, modify,
   # merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
   # permit persons to whom the Software is furnished to do so.
   #
   # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
   # INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
   # PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
   # HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
   # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   #
   # This code expects that you have AWS credentials setup per:
   # https://boto3.amazonaws.com/v1/documentation/api/latest/guide/quickstart.html
   from logging import basicConfig, getLogger, INFO
   
   from botocore.exceptions import ClientError
   
   from pyqldb.driver.qldb_driver import QldbDriver
   from pyqldbsamples.constants import Constants
   
   logger = getLogger(__name__)
   basicConfig(level=INFO)
   
   
   def create_qldb_driver(ledger_name=Constants.LEDGER_NAME, region_name=None, endpoint_url=None, boto3_session=None):
       """
       Create a QLDB driver for executing transactions.
   
       :type ledger_name: str
       :param ledger_name: The QLDB ledger name.
   
       :type region_name: str
       :param region_name: See [1].
   
       :type endpoint_url: str
       :param endpoint_url: See [1].
   
       :type boto3_session: :py:class:`boto3.session.Session`
       :param boto3_session: The boto3 session to create the client with (see [1]).
   
       :rtype: :py:class:`pyqldb.driver.qldb_driver.QldbDriver`
       :return: A QLDB driver object.
   
       [1]: `Boto3 Session.client Reference <https://boto3.amazonaws.com/v1/documentation/api/latest/reference/core/session.html#boto3.session.Session.client>`.
       """
       qldb_driver = QldbDriver(ledger_name=ledger_name, region_name=region_name, endpoint_url=endpoint_url,
                                boto3_session=boto3_session)
       return qldb_driver
   
   
   def main(ledger_name=Constants.LEDGER_NAME):
       """
       Connect to a given ledger using default settings.
       """
       try:
           with create_qldb_driver(ledger_name) as driver:
               logger.info('Listing table names ')
               for table in driver.list_tables():
                   logger.info(table)
       except ClientError as ce:
           logger.exception('Unable to list tables.')
           raise ce
   
   
   if __name__ == '__main__':
       main()

   참고

   • 원장에서 데이터 거래를 실행하려면 특정 원장에 연결할 QLDB 드라이버 객체를 생성해야 합니다. 이는 이전 단계에서 원장을 생성할 때 사용한 qldb_client 객체와는 다른 클라이언트 객체입니다. 이전 클라이언트는 에 나열된 관리 API 작업을 실행하는 데만 사용됩니다. 아마존 QLDB API 레퍼런스

   • 이 드라이버 객체를 생성할 때 원장 이름을 지정해야 합니다.

   2.x

   # Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
   # SPDX-License-Identifier: MIT-0
   #
   # Permission is hereby granted, free of charge, to any person obtaining a copy of this
   # software and associated documentation files (the "Software"), to deal in the Software
   # without restriction, including without limitation the rights to use, copy, modify,
   # merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
   # permit persons to whom the Software is furnished to do so.
   #
   # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
   # INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
   # PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
   # HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
   # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   #
   # This code expects that you have AWS credentials setup per:
   # https://boto3.amazonaws.com/v1/documentation/api/latest/guide/quickstart.html
   from logging import basicConfig, getLogger, INFO
   
   from botocore.exceptions import ClientError
   
   from pyqldb.driver.pooled_qldb_driver import PooledQldbDriver
   from pyqldbsamples.constants import Constants
   
   logger = getLogger(__name__)
   basicConfig(level=INFO)
   
   
   def create_qldb_driver(ledger_name=Constants.LEDGER_NAME, region_name=None, endpoint_url=None, boto3_session=None):
       """
       Create a QLDB driver for creating sessions.
   
       :type ledger_name: str
       :param ledger_name: The QLDB ledger name.
   
       :type region_name: str
       :param region_name: See [1].
   
       :type endpoint_url: str
       :param endpoint_url: See [1].
   
       :type boto3_session: :py:class:`boto3.session.Session`
       :param boto3_session: The boto3 session to create the client with (see [1]).
   
       :rtype: :py:class:`pyqldb.driver.pooled_qldb_driver.PooledQldbDriver`
       :return: A pooled QLDB driver object.
   
       [1]: `Boto3 Session.client Reference <https://boto3.amazonaws.com/v1/documentation/api/latest/reference/core/session.html#boto3.session.Session.client>`.
       """
       qldb_driver = PooledQldbDriver(ledger_name=ledger_name, region_name=region_name, endpoint_url=endpoint_url,
                                      boto3_session=boto3_session)
       return qldb_driver
   
   
   def create_qldb_session():
       """
       Retrieve a QLDB session object.
   
       :rtype: :py:class:`pyqldb.session.pooled_qldb_session.PooledQldbSession`
       :return: A pooled QLDB session object.
       """
       qldb_session = pooled_qldb_driver.get_session()
       return qldb_session
   
   
   pooled_qldb_driver = create_qldb_driver()
   
   
   if __name__ == '__main__':
       """
       Connect to a session for a given ledger using default settings.
       """
       try:
           qldb_session = create_qldb_session()
           logger.info('Listing table names ')
           for table in qldb_session.list_tables():
               logger.info(table)
       except ClientError:
           logger.exception('Unable to create session.')

   참고

   • 원장에서 데이터 트랜잭션을 실행하려면 특정 원장에 연결할 QLDB 드라이버 객체를 생성해야 합니다. 이는 이전 단계에서 원장을 생성할 때 사용한 qldb_client 객체와는 다른 클라이언트 객체입니다. 이전 클라이언트는 에 나열된 관리 API 작업을 실행하는 데만 사용됩니다. 아마존 QLDB API 레퍼런스

   • 먼저 풀링된 QLDB 드라이버 객체를 생성합니다. 이 드라이버를 생성할 때 원장 이름을 지정해야 합니다.

   • 그러면 이 풀링된 드라이버 객체에서 세션을 생성할 수 있습니다.

2. 프로그램을 실행하려면 다음 명령을 입력합니다.

   python connect_to_ledger.py