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Etapa 2: Testar a conectividade com o ledger
Importante
Aviso de fim do suporte: os clientes existentes poderão usar a Amazon QLDB até o final do suporte em 31/07/2025. Para obter mais detalhes, consulte Migrar um Amazon QLDB Ledger para o Amazon Aurora Postgre
Nesta etapa, você verifica se pode se conectar ao vehicle-registration
livro contábil na Amazon QLDB usando o endpoint de dados transacionais. API
Para testar a conexão com o ledger
-
Use o programa a seguir (
connect_to_ledger.py
) para criar uma conexão de sessão de dados com o ledgervehicle-registration
.- 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()
nota
-
Para executar transações de dados em seu livro contábil, você deve criar um objeto de QLDB driver para se conectar a um livro contábil específico. Esse é um objeto cliente diferente do objeto
qldb_client
que você usou na etapa anterior para criar o ledger. Esse cliente anterior é usado somente para executar as API operações de gerenciamento listadas noQLDBAPIReferência da Amazon. -
Você deve especificar um nome de ledger ao criar esse objeto de driver.
-
- 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.')
nota
-
Para executar transações de dados em seu livro contábil, você deve criar um objeto de QLDB driver para se conectar a um livro contábil específico. Esse é um objeto cliente diferente do objeto
qldb_client
que você usou na etapa anterior para criar o ledger. Esse cliente anterior é usado somente para executar as API operações de gerenciamento listadas noQLDBAPIReferência da Amazon. -
Primeiro, crie um objeto de QLDB driver agrupado. Você deve especificar um nome de ledger ao criar esse objeto de driver.
-
Em seguida, você pode criar sessões a partir desse objeto de driver agrupado.
-
-
Para executar o programa, digite o comando a seguir.
python connect_to_ledger.py
Para criar tabelas no ledger vehicle-registration
, vá para Etapa 3: criar tabelas, índices e dados de amostra.