第 1 步：创建新的分类账

重要

终止支持通知：现有客户将能够使用亚马逊，QLDB直到 2025 年 7 月 31 日终止支持。有关更多详细信息，请参阅将亚马逊QLDB账本迁移到亚马逊 Aurora Postgr SQL e。

在此步骤中，您将创建一个名为的新 Amazon QLDB 账本vehicle-registration。

创建新分类账

1. 查看以下文件（Constants.ts），其包含本教程中所有其他程序使用的常量值。

   /*
    * 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.
    */
   
   /**
    * Constant values used throughout this tutorial.
    */
   export const LEDGER_NAME = "vehicle-registration";
   export const LEDGER_NAME_WITH_TAGS = "tags";
   
   export const DRIVERS_LICENSE_TABLE_NAME = "DriversLicense";
   export const PERSON_TABLE_NAME = "Person";
   export const VEHICLE_REGISTRATION_TABLE_NAME = "VehicleRegistration";
   export const VEHICLE_TABLE_NAME = "Vehicle";
   
   export const GOV_ID_INDEX_NAME = "GovId";
   export const LICENSE_NUMBER_INDEX_NAME = "LicenseNumber";
   export const LICENSE_PLATE_NUMBER_INDEX_NAME = "LicensePlateNumber";
   export const PERSON_ID_INDEX_NAME = "PersonId";
   export const VIN_INDEX_NAME = "VIN";
   
   export const RETRY_LIMIT = 4;
   
   export const JOURNAL_EXPORT_S3_BUCKET_NAME_PREFIX = "qldb-tutorial-journal-export";
   export const USER_TABLES = "information_schema.user_tables";

2. 使用以下程序（CreateLedger.ts）创建名为 vehicle-registration 的分类账。

   /*
    * 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.
    */
   
   import { QLDB } from "aws-sdk";
   import {
       CreateLedgerRequest,
       CreateLedgerResponse,
       DescribeLedgerRequest,
       DescribeLedgerResponse
   } from "aws-sdk/clients/qldb";
   
   import { LEDGER_NAME } from "./qldb/Constants";
   import { error, log } from "./qldb/LogUtil";
   import { sleep } from "./qldb/Util";
   
   const LEDGER_CREATION_POLL_PERIOD_MS = 10000;
   const ACTIVE_STATE = "ACTIVE";
   
   /**
    * Create a new ledger with the specified name.
    * @param ledgerName Name of the ledger to be created.
    * @param qldbClient The QLDB control plane client to use.
    * @returns Promise which fulfills with a CreateLedgerResponse.
    */
   export async function createLedger(ledgerName: string, qldbClient: QLDB): Promise<CreateLedgerResponse> {
       log(`Creating a ledger named: ${ledgerName}...`);
       const request: CreateLedgerRequest = {
           Name: ledgerName,
           PermissionsMode: "ALLOW_ALL"
       }
       const result: CreateLedgerResponse = await qldbClient.createLedger(request).promise();
       log(`Success. Ledger state: ${result.State}.`);
       return result;
   }
   
   /**
    * Wait for the newly created ledger to become active.
    * @param ledgerName Name of the ledger to be checked on.
    * @param qldbClient The QLDB control plane client to use.
    * @returns Promise which fulfills with a DescribeLedgerResponse.
    */
   export async function waitForActive(ledgerName: string, qldbClient: QLDB): Promise<DescribeLedgerResponse> {
       log(`Waiting for ledger ${ledgerName} to become active...`);
       const request: DescribeLedgerRequest = {
           Name: ledgerName
       }
       while (true) {
           const result: DescribeLedgerResponse = await qldbClient.describeLedger(request).promise();
           if (result.State === ACTIVE_STATE) {
               log("Success. Ledger is active and ready to be used.");
               return result;
           }
           log("The ledger is still creating. Please wait...");
           await sleep(LEDGER_CREATION_POLL_PERIOD_MS);
       }
   }
   
   /**
    * Create a ledger and wait for it to be active.
    * @returns Promise which fulfills with void.
    */
   const main = async function(): Promise<void> {
       try {
           const qldbClient: QLDB = new QLDB();
           await createLedger(LEDGER_NAME, qldbClient);
           await waitForActive(LEDGER_NAME, qldbClient);
       } catch (e) {
           error(`Unable to create the ledger: ${e}`);
       }
   }
   
   if (require.main === module) {
       main();
   }

   注意

   • 在 createLedger 调用中，您必须指定分类账名称和权限模式。我们强烈建议使用 STANDARD 权限模式来最大限度地提高分类账数据的安全性。

   • 创建分类账时，将默认启用 删除保护。这是QLDB一项防止任何用户删除账本的功能。您可以选择使用QLDBAPI或 AWS Command Line Interface (AWS CLI) 在创建账本时禁用删除保护。

   • 您还可选择指定要附加到分类账的标签。

3. 要运行编译后的程序，请输入以下命令。

   node dist/CreateLedger.js

要验证您与新分类账的连接，请继续 第 2 步：测试与分类账的连接。