AWS 文档 AWS SDK示例 GitHub 存储库中还有更多SDK示例
本文属于机器翻译版本。若本译文内容与英语原文存在差异,则一律以英文原文为准。
使用 f SDK or JavaScript (v3) 的 Lambda 示例
以下代码示例向您展示了如何使用带有 Lambda 的 AWS SDK for JavaScript (v3) 来执行操作和实现常见场景。
基础知识是向您展示如何在服务中执行基本操作的代码示例。
操作是大型程序的代码摘录,必须在上下文中运行。您可以通过操作了解如何调用单个服务函数,还可以通过函数相关场景的上下文查看操作。
场景是向您展示如何通过在一个服务中调用多个函数或与其他 AWS 服务结合来完成特定任务的代码示例。
每个示例都包含一个指向完整源代码的链接,您可以在其中找到有关如何在上下文中设置和运行代码的说明。
开始使用
以下代码示例展示了如何开始使用 Lambda。
- SDK对于 JavaScript (v3)
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注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 import { LambdaClient, paginateListFunctions } from "@aws-sdk/client-lambda"; const client = new LambdaClient({}); export const helloLambda = async () => { const paginator = paginateListFunctions({ client }, {}); const functions = []; for await (const page of paginator) { const funcNames = page.Functions.map((f) => f.FunctionName); functions.push(...funcNames); } console.log("Functions:"); console.log(functions.join("\n")); return functions; };
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有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 ListFunctions” 中的。
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基础知识
以下代码示例展示了如何:
创建IAM角色和 Lambda 函数,然后上传处理程序代码。
使用单个参数来调用函数并获取结果。
更新函数代码并使用环境变量进行配置。
使用新参数来调用函数并获取结果。显示返回的执行日志。
列出账户函数,然后清除函数。
有关更多信息,请参阅使用控制台创建 Lambda 函数。
- SDK对于 JavaScript (v3)
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注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 创建一个 AWS Identity and Access Management (IAM) 角色来授予 Lambda 写入日志的权限。
logger.log(`Creating role (${NAME_ROLE_LAMBDA})...`); const response = await createRole(NAME_ROLE_LAMBDA); import { AttachRolePolicyCommand, IAMClient } from "@aws-sdk/client-iam"; const client = new IAMClient({}); /** * * @param {string} policyArn * @param {string} roleName */ export const attachRolePolicy = (policyArn, roleName) => { const command = new AttachRolePolicyCommand({ PolicyArn: policyArn, RoleName: roleName, }); return client.send(command); };
创建 Lambda 函数并上传处理程序代码。
const createFunction = async (funcName, roleArn) => { const client = new LambdaClient({}); const code = await readFile(`${dirname}../functions/${funcName}.zip`); const command = new CreateFunctionCommand({ Code: { ZipFile: code }, FunctionName: funcName, Role: roleArn, Architectures: [Architecture.arm64], Handler: "index.handler", // Required when sending a .zip file PackageType: PackageType.Zip, // Required when sending a .zip file Runtime: Runtime.nodejs16x, // Required when sending a .zip file }); return client.send(command); };
调用单参数函数并得出结果。
const invoke = async (funcName, payload) => { const client = new LambdaClient({}); const command = new InvokeCommand({ FunctionName: funcName, Payload: JSON.stringify(payload), LogType: LogType.Tail, }); const { Payload, LogResult } = await client.send(command); const result = Buffer.from(Payload).toString(); const logs = Buffer.from(LogResult, "base64").toString(); return { logs, result }; };
更新函数代码并使用环境变量配置其 Lambda 环境。
const updateFunctionCode = async (funcName, newFunc) => { const client = new LambdaClient({}); const code = await readFile(`${dirname}../functions/${newFunc}.zip`); const command = new UpdateFunctionCodeCommand({ ZipFile: code, FunctionName: funcName, Architectures: [Architecture.arm64], Handler: "index.handler", // Required when sending a .zip file PackageType: PackageType.Zip, // Required when sending a .zip file Runtime: Runtime.nodejs16x, // Required when sending a .zip file }); return client.send(command); }; const updateFunctionConfiguration = (funcName) => { const client = new LambdaClient({}); const config = readFileSync(`${dirname}../functions/config.json`).toString(); const command = new UpdateFunctionConfigurationCommand({ ...JSON.parse(config), FunctionName: funcName, }); const result = client.send(command); waitForFunctionUpdated({ FunctionName: funcName }); return result; };
列出您账户的函数。
const listFunctions = () => { const client = new LambdaClient({}); const command = new ListFunctionsCommand({}); return client.send(command); };
删除该IAM角色和 Lambda 函数。
import { DeleteRoleCommand, IAMClient } from "@aws-sdk/client-iam"; const client = new IAMClient({}); /** * * @param {string} roleName */ export const deleteRole = (roleName) => { const command = new DeleteRoleCommand({ RoleName: roleName }); return client.send(command); }; /** * @param {string} funcName */ const deleteFunction = (funcName) => { const client = new LambdaClient({}); const command = new DeleteFunctionCommand({ FunctionName: funcName }); return client.send(command); };
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有关API详细信息,请参阅 “参AWS SDK for JavaScript API考” 中的以下主题。
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操作
以下代码示例演示如何使用 CreateFunction
。
- SDK对于 JavaScript (v3)
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注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 const createFunction = async (funcName, roleArn) => { const client = new LambdaClient({}); const code = await readFile(`${dirname}../functions/${funcName}.zip`); const command = new CreateFunctionCommand({ Code: { ZipFile: code }, FunctionName: funcName, Role: roleArn, Architectures: [Architecture.arm64], Handler: "index.handler", // Required when sending a .zip file PackageType: PackageType.Zip, // Required when sending a .zip file Runtime: Runtime.nodejs16x, // Required when sending a .zip file }); return client.send(command); };
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有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 CreateFunction” 中的。
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以下代码示例演示如何使用 DeleteFunction
。
- SDK对于 JavaScript (v3)
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注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 /** * @param {string} funcName */ const deleteFunction = (funcName) => { const client = new LambdaClient({}); const command = new DeleteFunctionCommand({ FunctionName: funcName }); return client.send(command); };
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有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 DeleteFunction” 中的。
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以下代码示例演示如何使用 GetFunction
。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 const getFunction = (funcName) => { const client = new LambdaClient({}); const command = new GetFunctionCommand({ FunctionName: funcName }); return client.send(command); };
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有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 GetFunction” 中的。
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以下代码示例演示如何使用 Invoke
。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 const invoke = async (funcName, payload) => { const client = new LambdaClient({}); const command = new InvokeCommand({ FunctionName: funcName, Payload: JSON.stringify(payload), LogType: LogType.Tail, }); const { Payload, LogResult } = await client.send(command); const result = Buffer.from(Payload).toString(); const logs = Buffer.from(LogResult, "base64").toString(); return { logs, result }; };
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有关API详细信息,请参见在AWS SDK for JavaScript API参考中调用。
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以下代码示例演示如何使用 ListFunctions
。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 const listFunctions = () => { const client = new LambdaClient({}); const command = new ListFunctionsCommand({}); return client.send(command); };
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有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 ListFunctions” 中的。
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以下代码示例演示如何使用 UpdateFunctionCode
。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 const updateFunctionCode = async (funcName, newFunc) => { const client = new LambdaClient({}); const code = await readFile(`${dirname}../functions/${newFunc}.zip`); const command = new UpdateFunctionCodeCommand({ ZipFile: code, FunctionName: funcName, Architectures: [Architecture.arm64], Handler: "index.handler", // Required when sending a .zip file PackageType: PackageType.Zip, // Required when sending a .zip file Runtime: Runtime.nodejs16x, // Required when sending a .zip file }); return client.send(command); };
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有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 UpdateFunctionCode” 中的。
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以下代码示例演示如何使用 UpdateFunctionConfiguration
。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 const updateFunctionConfiguration = (funcName) => { const client = new LambdaClient({}); const config = readFileSync(`${dirname}../functions/config.json`).toString(); const command = new UpdateFunctionConfigurationCommand({ ...JSON.parse(config), FunctionName: funcName, }); const result = client.send(command); waitForFunctionUpdated({ FunctionName: funcName }); return result; };
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有关API详细信息,请参阅 “AWS SDK for JavaScript API参考 UpdateFunctionConfiguration” 中的。
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场景
以下代码示例显示了如何使用 Lambda 函数自动确认已知的 Amazon Cognito 用户。
配置用户池以调用
PreSignUp
触发器的 Lambda 函数。将用户注册到 Amazon Cognito
Lambda 函数会扫描 DynamoDB 表并自动确认已知用户。
以新用户身份登录,然后清理资源。
- SDK对于 JavaScript (v3)
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注意
还有更多相关信息 GitHub。查找完整示例,学习如何在 AWS 代码示例存储库
中进行设置和运行。 配置交互式 “场景” 运行。 JavaScript (v3) 示例共享一个场景运行器,以简化复杂的示例。完整的源代码已打开 GitHub。
import { AutoConfirm } from "./scenario-auto-confirm.js"; /** * The context is passed to every scenario. Scenario steps * will modify the context. */ const context = { errors: [], users: [ { UserName: "test_user_1", UserEmail: "test_email_1@example.com", }, { UserName: "test_user_2", UserEmail: "test_email_2@example.com", }, { UserName: "test_user_3", UserEmail: "test_email_3@example.com", }, ], }; /** * Three Scenarios are created for the workflow. A Scenario is an orchestration class * that simplifies running a series of steps. */ export const scenarios = { // Demonstrate automatically confirming known users in a database. "auto-confirm": AutoConfirm(context), }; // Call function if run directly import { fileURLToPath } from "node:url"; import { parseScenarioArgs } from "@aws-doc-sdk-examples/lib/scenario/index.js"; if (process.argv[1] === fileURLToPath(import.meta.url)) { parseScenarioArgs(scenarios, { name: "Cognito user pools and triggers", description: "Demonstrate how to use the AWS SDKs to customize Amazon Cognito authentication behavior.", }); }
此场景演示自动确认已知用户。它编排了示例步骤。
import { wait } from "@aws-doc-sdk-examples/lib/utils/util-timers.js"; import { Scenario, ScenarioAction, ScenarioInput, ScenarioOutput, } from "@aws-doc-sdk-examples/lib/scenario/scenario.js"; import { getStackOutputs, logCleanUpReminder, promptForStackName, promptForStackRegion, skipWhenErrors, } from "./steps-common.js"; import { populateTable } from "./actions/dynamodb-actions.js"; import { addPreSignUpHandler, deleteUser, getUser, signIn, signUpUser, } from "./actions/cognito-actions.js"; import { getLatestLogStreamForLambda, getLogEvents, } from "./actions/cloudwatch-logs-actions.js"; /** * @typedef {{ * errors: Error[], * password: string, * users: { UserName: string, UserEmail: string }[], * selectedUser?: string, * stackName?: string, * stackRegion?: string, * token?: string, * confirmDeleteSignedInUser?: boolean, * TableName?: string, * UserPoolClientId?: string, * UserPoolId?: string, * UserPoolArn?: string, * AutoConfirmHandlerArn?: string, * AutoConfirmHandlerName?: string * }} State */ const greeting = new ScenarioOutput( "greeting", (/** @type {State} */ state) => `This demo will populate some users into the \ database created as part of the "${state.stackName}" stack. \ Then the autoConfirmHandler will be linked to the PreSignUp \ trigger from Cognito. Finally, you will choose a user to sign up.`, { skipWhen: skipWhenErrors }, ); const logPopulatingUsers = new ScenarioOutput( "logPopulatingUsers", "Populating the DynamoDB table with some users.", { skipWhenErrors: skipWhenErrors }, ); const logPopulatingUsersComplete = new ScenarioOutput( "logPopulatingUsersComplete", "Done populating users.", { skipWhen: skipWhenErrors }, ); const populateUsers = new ScenarioAction( "populateUsers", async (/** @type {State} */ state) => { const [_, err] = await populateTable({ region: state.stackRegion, tableName: state.TableName, items: state.users, }); if (err) { state.errors.push(err); } }, { skipWhen: skipWhenErrors, }, ); const logSetupSignUpTrigger = new ScenarioOutput( "logSetupSignUpTrigger", "Setting up the PreSignUp trigger for the Cognito User Pool.", { skipWhen: skipWhenErrors }, ); const setupSignUpTrigger = new ScenarioAction( "setupSignUpTrigger", async (/** @type {State} */ state) => { const [_, err] = await addPreSignUpHandler({ region: state.stackRegion, userPoolId: state.UserPoolId, handlerArn: state.AutoConfirmHandlerArn, }); if (err) { state.errors.push(err); } }, { skipWhen: skipWhenErrors, }, ); const logSetupSignUpTriggerComplete = new ScenarioOutput( "logSetupSignUpTriggerComplete", ( /** @type {State} */ state, ) => `The lambda function "${state.AutoConfirmHandlerName}" \ has been configured as the PreSignUp trigger handler for the user pool "${state.UserPoolId}".`, { skipWhen: skipWhenErrors }, ); const selectUser = new ScenarioInput( "selectedUser", "Select a user to sign up.", { type: "select", choices: (/** @type {State} */ state) => state.users.map((u) => u.UserName), skipWhen: skipWhenErrors, default: (/** @type {State} */ state) => state.users[0].UserName, }, ); const checkIfUserAlreadyExists = new ScenarioAction( "checkIfUserAlreadyExists", async (/** @type {State} */ state) => { const [user, err] = await getUser({ region: state.stackRegion, userPoolId: state.UserPoolId, username: state.selectedUser, }); if (err?.name === "UserNotFoundException") { // Do nothing. We're not expecting the user to exist before // sign up is complete. return; } if (err) { state.errors.push(err); return; } if (user) { state.errors.push( new Error( `The user "${state.selectedUser}" already exists in the user pool "${state.UserPoolId}".`, ), ); } }, { skipWhen: skipWhenErrors, }, ); const createPassword = new ScenarioInput( "password", "Enter a password that has at least eight characters, uppercase, lowercase, numbers and symbols.", { type: "password", skipWhen: skipWhenErrors, default: "Abcd1234!" }, ); const logSignUpExistingUser = new ScenarioOutput( "logSignUpExistingUser", (/** @type {State} */ state) => `Signing up user "${state.selectedUser}".`, { skipWhen: skipWhenErrors }, ); const signUpExistingUser = new ScenarioAction( "signUpExistingUser", async (/** @type {State} */ state) => { const signUp = (password) => signUpUser({ region: state.stackRegion, userPoolClientId: state.UserPoolClientId, username: state.selectedUser, email: state.users.find((u) => u.UserName === state.selectedUser) .UserEmail, password, }); let [_, err] = await signUp(state.password); while (err?.name === "InvalidPasswordException") { console.warn("The password you entered was invalid."); await createPassword.handle(state); [_, err] = await signUp(state.password); } if (err) { state.errors.push(err); } }, { skipWhen: skipWhenErrors }, ); const logSignUpExistingUserComplete = new ScenarioOutput( "logSignUpExistingUserComplete", (/** @type {State} */ state) => `"${state.selectedUser} was signed up successfully.`, { skipWhen: skipWhenErrors }, ); const logLambdaLogs = new ScenarioAction( "logLambdaLogs", async (/** @type {State} */ state) => { console.log( "Waiting a few seconds to let Lambda write to CloudWatch Logs...\n", ); await wait(10); const [logStream, logStreamErr] = await getLatestLogStreamForLambda({ functionName: state.AutoConfirmHandlerName, region: state.stackRegion, }); if (logStreamErr) { state.errors.push(logStreamErr); return; } console.log( `Getting some recent events from log stream "${logStream.logStreamName}"`, ); const [logEvents, logEventsErr] = await getLogEvents({ functionName: state.AutoConfirmHandlerName, region: state.stackRegion, eventCount: 10, logStreamName: logStream.logStreamName, }); if (logEventsErr) { state.errors.push(logEventsErr); return; } console.log(logEvents.map((ev) => `\t${ev.message}`).join("")); }, { skipWhen: skipWhenErrors }, ); const logSignInUser = new ScenarioOutput( "logSignInUser", (/** @type {State} */ state) => `Let's sign in as ${state.selectedUser}`, { skipWhen: skipWhenErrors }, ); const signInUser = new ScenarioAction( "signInUser", async (/** @type {State} */ state) => { const [response, err] = await signIn({ region: state.stackRegion, clientId: state.UserPoolClientId, username: state.selectedUser, password: state.password, }); if (err?.name === "PasswordResetRequiredException") { state.errors.push(new Error("Please reset your password.")); return; } if (err) { state.errors.push(err); return; } state.token = response?.AuthenticationResult?.AccessToken; }, { skipWhen: skipWhenErrors }, ); const logSignInUserComplete = new ScenarioOutput( "logSignInUserComplete", (/** @type {State} */ state) => `Successfully signed in. Your access token starts with: ${state.token.slice(0, 11)}`, { skipWhen: skipWhenErrors }, ); const confirmDeleteSignedInUser = new ScenarioInput( "confirmDeleteSignedInUser", "Do you want to delete the currently signed in user?", { type: "confirm", skipWhen: skipWhenErrors }, ); const deleteSignedInUser = new ScenarioAction( "deleteSignedInUser", async (/** @type {State} */ state) => { const [_, err] = await deleteUser({ region: state.stackRegion, accessToken: state.token, }); if (err) { state.errors.push(err); } }, { skipWhen: (/** @type {State} */ state) => skipWhenErrors(state) || !state.confirmDeleteSignedInUser, }, ); const logErrors = new ScenarioOutput( "logErrors", (/** @type {State}*/ state) => { const errorList = state.errors .map((err) => ` - ${err.name}: ${err.message}`) .join("\n"); return `Scenario errors found:\n${errorList}`; }, { // Don't log errors when there aren't any! skipWhen: (/** @type {State} */ state) => state.errors.length === 0, }, ); export const AutoConfirm = (context) => new Scenario( "AutoConfirm", [ promptForStackName, promptForStackRegion, getStackOutputs, greeting, logPopulatingUsers, populateUsers, logPopulatingUsersComplete, logSetupSignUpTrigger, setupSignUpTrigger, logSetupSignUpTriggerComplete, selectUser, checkIfUserAlreadyExists, createPassword, logSignUpExistingUser, signUpExistingUser, logSignUpExistingUserComplete, logLambdaLogs, logSignInUser, signInUser, logSignInUserComplete, confirmDeleteSignedInUser, deleteSignedInUser, logCleanUpReminder, logErrors, ], context, );
这些步骤与其他场景共享。
import { ScenarioAction, ScenarioInput, ScenarioOutput, } from "@aws-doc-sdk-examples/lib/scenario/scenario.js"; import { getCfnOutputs } from "@aws-doc-sdk-examples/lib/sdk/cfn-outputs.js"; export const skipWhenErrors = (state) => state.errors.length > 0; export const getStackOutputs = new ScenarioAction( "getStackOutputs", async (state) => { if (!state.stackName || !state.stackRegion) { state.errors.push( new Error( "No stack name or region provided. The stack name and \ region are required to fetch CFN outputs relevant to this example.", ), ); return; } const outputs = await getCfnOutputs(state.stackName, state.stackRegion); Object.assign(state, outputs); }, ); export const promptForStackName = new ScenarioInput( "stackName", "Enter the name of the stack you deployed earlier.", { type: "input", default: "PoolsAndTriggersStack" }, ); export const promptForStackRegion = new ScenarioInput( "stackRegion", "Enter the region of the stack you deployed earlier.", { type: "input", default: "us-east-1" }, ); export const logCleanUpReminder = new ScenarioOutput( "logCleanUpReminder", "All done. Remember to run 'cdk destroy' to teardown the stack.", { skipWhen: skipWhenErrors }, );
带有 Lambda 函数的
PreSignUp
触发器的处理程序。import type { PreSignUpTriggerEvent, Handler } from "aws-lambda"; import type { UserRepository } from "./user-repository"; import { DynamoDBUserRepository } from "./user-repository"; export class PreSignUpHandler { private userRepository: UserRepository; constructor(userRepository: UserRepository) { this.userRepository = userRepository; } private isPreSignUpTriggerSource(event: PreSignUpTriggerEvent): boolean { return event.triggerSource === "PreSignUp_SignUp"; } private getEventUserEmail(event: PreSignUpTriggerEvent): string { return event.request.userAttributes.email; } async handlePreSignUpTriggerEvent( event: PreSignUpTriggerEvent, ): Promise<PreSignUpTriggerEvent> { console.log( `Received presignup from ${event.triggerSource} for user '${event.userName}'`, ); if (!this.isPreSignUpTriggerSource(event)) { return event; } const eventEmail = this.getEventUserEmail(event); console.log(`Looking up email ${eventEmail}.`); const storedUserInfo = await this.userRepository.getUserInfoByEmail(eventEmail); if (!storedUserInfo) { console.log( `Email ${eventEmail} not found. Email verification is required.`, ); return event; } if (storedUserInfo.UserName !== event.userName) { console.log( `UserEmail ${eventEmail} found, but stored UserName '${storedUserInfo.UserName}' does not match supplied UserName '${event.userName}'. Verification is required.`, ); } else { console.log( `UserEmail ${eventEmail} found with matching UserName ${storedUserInfo.UserName}. User is confirmed.`, ); event.response.autoConfirmUser = true; event.response.autoVerifyEmail = true; } return event; } } const createPreSignUpHandler = (): PreSignUpHandler => { const tableName = process.env.TABLE_NAME; if (!tableName) { throw new Error("TABLE_NAME environment variable is not set"); } const userRepository = new DynamoDBUserRepository(tableName); return new PreSignUpHandler(userRepository); }; export const handler: Handler = async (event: PreSignUpTriggerEvent) => { const preSignUpHandler = createPreSignUpHandler(); return preSignUpHandler.handlePreSignUpTriggerEvent(event); };
CloudWatch 日志操作模块。
import { CloudWatchLogsClient, GetLogEventsCommand, OrderBy, paginateDescribeLogStreams, } from "@aws-sdk/client-cloudwatch-logs"; /** * Get the latest log stream for a Lambda function. * @param {{ functionName: string, region: string }} config * @returns {Promise<[import("@aws-sdk/client-cloudwatch-logs").LogStream | null, unknown]>} */ export const getLatestLogStreamForLambda = async ({ functionName, region }) => { try { const logGroupName = `/aws/lambda/${functionName}`; const cwlClient = new CloudWatchLogsClient({ region }); const paginator = paginateDescribeLogStreams( { client: cwlClient }, { descending: true, limit: 1, orderBy: OrderBy.LastEventTime, logGroupName, }, ); for await (const page of paginator) { return [page.logStreams[0], null]; } } catch (err) { return [null, err]; } }; /** * Get the log events for a Lambda function's log stream. * @param {{ * functionName: string, * logStreamName: string, * eventCount: number, * region: string * }} config * @returns {Promise<[import("@aws-sdk/client-cloudwatch-logs").OutputLogEvent[] | null, unknown]>} */ export const getLogEvents = async ({ functionName, logStreamName, eventCount, region, }) => { try { const cwlClient = new CloudWatchLogsClient({ region }); const logGroupName = `/aws/lambda/${functionName}`; const response = await cwlClient.send( new GetLogEventsCommand({ logStreamName: logStreamName, limit: eventCount, logGroupName: logGroupName, }), ); return [response.events, null]; } catch (err) { return [null, err]; } };
亚马逊 Cognito 操作模块。
import { AdminGetUserCommand, CognitoIdentityProviderClient, DeleteUserCommand, InitiateAuthCommand, SignUpCommand, UpdateUserPoolCommand, } from "@aws-sdk/client-cognito-identity-provider"; /** * Connect a Lambda function to the PreSignUp trigger for a Cognito user pool * @param {{ region: string, userPoolId: string, handlerArn: string }} config * @returns {Promise<[import("@aws-sdk/client-cognito-identity-provider").UpdateUserPoolCommandOutput | null, unknown]>} */ export const addPreSignUpHandler = async ({ region, userPoolId, handlerArn, }) => { try { const cognitoClient = new CognitoIdentityProviderClient({ region, }); const command = new UpdateUserPoolCommand({ UserPoolId: userPoolId, LambdaConfig: { PreSignUp: handlerArn, }, }); const response = await cognitoClient.send(command); return [response, null]; } catch (err) { return [null, err]; } }; /** * Attempt to register a user to a user pool with a given username and password. * @param {{ * region: string, * userPoolClientId: string, * username: string, * email: string, * password: string * }} config * @returns {Promise<[import("@aws-sdk/client-cognito-identity-provider").SignUpCommandOutput | null, unknown]>} */ export const signUpUser = async ({ region, userPoolClientId, username, email, password, }) => { try { const cognitoClient = new CognitoIdentityProviderClient({ region, }); const response = await cognitoClient.send( new SignUpCommand({ ClientId: userPoolClientId, Username: username, Password: password, UserAttributes: [{ Name: "email", Value: email }], }), ); return [response, null]; } catch (err) { return [null, err]; } }; /** * Sign in a user to Amazon Cognito using a username and password authentication flow. * @param {{ region: string, clientId: string, username: string, password: string }} config * @returns {Promise<[import("@aws-sdk/client-cognito-identity-provider").InitiateAuthCommandOutput | null, unknown]>} */ export const signIn = async ({ region, clientId, username, password }) => { try { const cognitoClient = new CognitoIdentityProviderClient({ region }); const response = await cognitoClient.send( new InitiateAuthCommand({ AuthFlow: "USER_PASSWORD_AUTH", ClientId: clientId, AuthParameters: { USERNAME: username, PASSWORD: password }, }), ); return [response, null]; } catch (err) { return [null, err]; } }; /** * Retrieve an existing user from a user pool. * @param {{ region: string, userPoolId: string, username: string }} config * @returns {Promise<[import("@aws-sdk/client-cognito-identity-provider").AdminGetUserCommandOutput | null, unknown]>} */ export const getUser = async ({ region, userPoolId, username }) => { try { const cognitoClient = new CognitoIdentityProviderClient({ region }); const response = await cognitoClient.send( new AdminGetUserCommand({ UserPoolId: userPoolId, Username: username, }), ); return [response, null]; } catch (err) { return [null, err]; } }; /** * Delete the signed-in user. Useful for allowing a user to delete their * own profile. * @param {{ region: string, accessToken: string }} config * @returns {Promise<[import("@aws-sdk/client-cognito-identity-provider").DeleteUserCommandOutput | null, unknown]>} */ export const deleteUser = async ({ region, accessToken }) => { try { const client = new CognitoIdentityProviderClient({ region }); const response = await client.send( new DeleteUserCommand({ AccessToken: accessToken }), ); return [response, null]; } catch (err) { return [null, err]; } };
DynamoDB 操作模块。
import { DynamoDBClient } from "@aws-sdk/client-dynamodb"; import { BatchWriteCommand, DynamoDBDocumentClient, } from "@aws-sdk/lib-dynamodb"; /** * Populate a DynamoDB table with provide items. * @param {{ region: string, tableName: string, items: Record<string, unknown>[] }} config * @returns {Promise<[import("@aws-sdk/lib-dynamodb").BatchWriteCommandOutput | null, unknown]>} */ export const populateTable = async ({ region, tableName, items }) => { try { const ddbClient = new DynamoDBClient({ region }); const docClient = DynamoDBDocumentClient.from(ddbClient); const response = await docClient.send( new BatchWriteCommand({ RequestItems: { [tableName]: items.map((item) => ({ PutRequest: { Item: item, }, })), }, }), ); return [response, null]; } catch (err) { return [null, err]; } };
-
有关API详细信息,请参阅 “参AWS SDK for JavaScript API考” 中的以下主题。
-
以下代码示例演示如何创建无服务器应用程序,让用户能够使用标签管理照片。
以下代码示例说明如何创建应用程序来分析客户意见卡、翻译其母语、确定其情绪并根据译后的文本生成音频文件。
- SDK对于 JavaScript (v3)
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此示例应用程序可分析并存储客户反馈卡。具体来说,它满足了纽约市一家虚构酒店的需求。酒店以实体意见卡的形式收集来自不同语种的客人的反馈。该反馈通过 Web 客户端上传到应用程序中。意见卡图片上传后,将执行以下步骤:
-
使用 Amazon Textract 从图片中提取文本。
-
Amazon Comprehend 确定所提取文本的情绪及其语言。
-
使用 Amazon Translate 将所提取文本翻译为英语。
-
Amazon Polly 根据所提取文本合成音频文件。
完整的应用程序可使用 AWS CDK 进行部署。有关源代码和部署说明,请参阅中的项目 GitHub
。以下摘录显示了在 Lambda 函数中 AWS SDK for JavaScript 是如何使用的。 import { ComprehendClient, DetectDominantLanguageCommand, DetectSentimentCommand, } from "@aws-sdk/client-comprehend"; /** * Determine the language and sentiment of the extracted text. * * @param {{ source_text: string}} extractTextOutput */ export const handler = async (extractTextOutput) => { const comprehendClient = new ComprehendClient({}); const detectDominantLanguageCommand = new DetectDominantLanguageCommand({ Text: extractTextOutput.source_text, }); // The source language is required for sentiment analysis and // translation in the next step. const { Languages } = await comprehendClient.send( detectDominantLanguageCommand, ); const languageCode = Languages[0].LanguageCode; const detectSentimentCommand = new DetectSentimentCommand({ Text: extractTextOutput.source_text, LanguageCode: languageCode, }); const { Sentiment } = await comprehendClient.send(detectSentimentCommand); return { sentiment: Sentiment, language_code: languageCode, }; };
import { DetectDocumentTextCommand, TextractClient, } from "@aws-sdk/client-textract"; /** * Fetch the S3 object from the event and analyze it using Amazon Textract. * * @param {import("@types/aws-lambda").EventBridgeEvent<"Object Created">} eventBridgeS3Event */ export const handler = async (eventBridgeS3Event) => { const textractClient = new TextractClient(); const detectDocumentTextCommand = new DetectDocumentTextCommand({ Document: { S3Object: { Bucket: eventBridgeS3Event.bucket, Name: eventBridgeS3Event.object, }, }, }); // Textract returns a list of blocks. A block can be a line, a page, word, etc. // Each block also contains geometry of the detected text. // For more information on the Block type, see https://docs.aws.amazon.com/textract/latest/dg/API_Block.html. const { Blocks } = await textractClient.send(detectDocumentTextCommand); // For the purpose of this example, we are only interested in words. const extractedWords = Blocks.filter((b) => b.BlockType === "WORD").map( (b) => b.Text, ); return extractedWords.join(" "); };
import { PollyClient, SynthesizeSpeechCommand } from "@aws-sdk/client-polly"; import { S3Client } from "@aws-sdk/client-s3"; import { Upload } from "@aws-sdk/lib-storage"; /** * Synthesize an audio file from text. * * @param {{ bucket: string, translated_text: string, object: string}} sourceDestinationConfig */ export const handler = async (sourceDestinationConfig) => { const pollyClient = new PollyClient({}); const synthesizeSpeechCommand = new SynthesizeSpeechCommand({ Engine: "neural", Text: sourceDestinationConfig.translated_text, VoiceId: "Ruth", OutputFormat: "mp3", }); const { AudioStream } = await pollyClient.send(synthesizeSpeechCommand); const audioKey = `${sourceDestinationConfig.object}.mp3`; // Store the audio file in S3. const s3Client = new S3Client(); const upload = new Upload({ client: s3Client, params: { Bucket: sourceDestinationConfig.bucket, Key: audioKey, Body: AudioStream, ContentType: "audio/mp3", }, }); await upload.done(); return audioKey; };
import { TranslateClient, TranslateTextCommand, } from "@aws-sdk/client-translate"; /** * Translate the extracted text to English. * * @param {{ extracted_text: string, source_language_code: string}} textAndSourceLanguage */ export const handler = async (textAndSourceLanguage) => { const translateClient = new TranslateClient({}); const translateCommand = new TranslateTextCommand({ SourceLanguageCode: textAndSourceLanguage.source_language_code, TargetLanguageCode: "en", Text: textAndSourceLanguage.extracted_text, }); const { TranslatedText } = await translateClient.send(translateCommand); return { translated_text: TranslatedText }; };
本示例中使用的服务
Amazon Comprehend
Lambda
Amazon Polly
Amazon Textract
Amazon Translate
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以下代码示例显示了如何从浏览器调用 AWS Lambda 函数。
- SDK对于 JavaScript (v3)
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您可以创建一个基于浏览器的应用程序,该应用程序使用 AWS Lambda 函数更新包含用户选择的 Amazon DynamoDB 表。此应用程序使用 AWS SDK for JavaScript v3。
有关如何设置和运行的完整源代码和说明,请参阅上的完整示例GitHub
。 本示例中使用的服务
DynamoDB
Lambda
以下代码示例展示了如何创建由 Amazon API Gateway 调用的 AWS Lambda 函数。
- SDK对于 JavaScript (v3)
-
演示如何使用 Lambda JavaScript 运行时创建 AWS Lambda 函数。API此示例调用不同的 AWS 服务来执行特定的用例。此示例演示如何创建由 Amazon API Gateway 调用的 Lambda 函数,该函数会扫描亚马逊 DynamoDB 表中的工作周年纪念日,并使用亚马逊简单通知服务 (AmazonSNS) 向您的员工发送一条短信,祝贺他们在一周年之日向他们表示祝贺。
有关如何设置和运行的完整源代码和说明,请参阅上的完整示例GitHub
。 该示例也可在 AWS SDK for JavaScript v3 开发人员指南中找到。
本示例中使用的服务
API网关
DynamoDB
Lambda
Amazon SNS
以下代码示例显示如何创建由 Amazon EventBridge 计划事件调用的 AWS Lambda 函数。
- SDK对于 JavaScript (v3)
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演示如何创建调用函数的 Amazon EventBridge 计划事件。 AWS Lambda 配置 EventBridge 为使用 cron 表达式来调度 Lambda 函数的调用时间。在此示例中,您将使用 Lambda 运行时创建一个 Lambda 函数。 JavaScript API此示例调用不同的 AWS 服务来执行特定的用例。此示例展示了如何创建一个应用程序,在其一周年纪念日时向员工发送移动短信表示祝贺。
有关如何设置和运行的完整源代码和说明,请参阅上的完整示例GitHub
。 该示例也可在 AWS SDK for JavaScript v3 开发人员指南中找到。
本示例中使用的服务
DynamoDB
EventBridge
Lambda
Amazon SNS
无服务器示例
以下代码示例说明如何实现连接到数据库的 Lambda 函数。RDS该函数发出一个简单的数据库请求并返回结果。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用在 Lambda 函数中连接到亚马逊RDS数据库。 JavaScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 /* Node.js code here. */ // ES6+ example import { Signer } from "@aws-sdk/rds-signer"; import mysql from 'mysql2/promise'; async function createAuthToken() { // Define connection authentication parameters const dbinfo = { hostname: process.env.ProxyHostName, port: process.env.Port, username: process.env.DBUserName, region: process.env.AWS_REGION, } // Create RDS Signer object const signer = new Signer(dbinfo); // Request authorization token from RDS, specifying the username const token = await signer.getAuthToken(); return token; } async function dbOps() { // Obtain auth token const token = await createAuthToken(); // Define connection configuration let connectionConfig = { host: process.env.ProxyHostName, user: process.env.DBUserName, password: token, database: process.env.DBName, ssl: 'Amazon RDS' } // Create the connection to the DB const conn = await mysql.createConnection(connectionConfig); // Obtain the result of the query const [res,] = await conn.execute('select ?+? as sum', [3, 2]); return res; } export const handler = async (event) => { // Execute database flow const result = await dbOps(); // Return result return { statusCode: 200, body: JSON.stringify("The selected sum is: " + result[0].sum) } };
使用在 Lambda 函数中连接到亚马逊RDS数据库。 TypeScript
import { Signer } from "@aws-sdk/rds-signer"; import mysql from 'mysql2/promise'; // RDS settings // Using '!' (non-null assertion operator) to tell the TypeScript compiler that the DB settings are not null or undefined, const proxy_host_name = process.env.PROXY_HOST_NAME! const port = parseInt(process.env.PORT!) const db_name = process.env.DB_NAME! const db_user_name = process.env.DB_USER_NAME! const aws_region = process.env.AWS_REGION! async function createAuthToken(): Promise<string> { // Create RDS Signer object const signer = new Signer({ hostname: proxy_host_name, port: port, region: aws_region, username: db_user_name }); // Request authorization token from RDS, specifying the username const token = await signer.getAuthToken(); return token; } async function dbOps(): Promise<mysql.QueryResult | undefined> { try { // Obtain auth token const token = await createAuthToken(); const conn = await mysql.createConnection({ host: proxy_host_name, user: db_user_name, password: token, database: db_name, ssl: 'Amazon RDS' // Ensure you have the CA bundle for SSL connection }); const [rows, fields] = await conn.execute('SELECT ? + ? AS sum', [3, 2]); console.log('result:', rows); return rows; } catch (err) { console.log(err); } } export const lambdaHandler = async (event: any): Promise<{ statusCode: number; body: string }> => { // Execute database flow const result = await dbOps(); // Return error is result is undefined if (result == undefined) return { statusCode: 500, body: JSON.stringify(`Error with connection to DB host`) } // Return result return { statusCode: 200, body: JSON.stringify(`The selected sum is: ${result[0].sum}`) }; };
以下代码示例展示了如何实现一个 Lambda 函数,该函数接收因接收来自 Kinesis 流的记录而触发的事件。该函数检索 Kinesis 有效负载,将 Base64 解码,并记录下记录内容。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 消耗 Kinesis 事件。 JavaScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 exports.handler = async (event, context) => { for (const record of event.Records) { try { console.log(`Processed Kinesis Event - EventID: ${record.eventID}`); const recordData = await getRecordDataAsync(record.kinesis); console.log(`Record Data: ${recordData}`); // TODO: Do interesting work based on the new data } catch (err) { console.error(`An error occurred ${err}`); throw err; } } console.log(`Successfully processed ${event.Records.length} records.`); }; async function getRecordDataAsync(payload) { var data = Buffer.from(payload.data, "base64").toString("utf-8"); await Promise.resolve(1); //Placeholder for actual async work return data; }
使用 Lambda 消耗 Kinesis 事件。 TypeScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 import { KinesisStreamEvent, Context, KinesisStreamHandler, KinesisStreamRecordPayload, } from "aws-lambda"; import { Buffer } from "buffer"; import { Logger } from "@aws-lambda-powertools/logger"; const logger = new Logger({ logLevel: "INFO", serviceName: "kinesis-stream-handler-sample", }); export const functionHandler: KinesisStreamHandler = async ( event: KinesisStreamEvent, context: Context ): Promise<void> => { for (const record of event.Records) { try { logger.info(`Processed Kinesis Event - EventID: ${record.eventID}`); const recordData = await getRecordDataAsync(record.kinesis); logger.info(`Record Data: ${recordData}`); // TODO: Do interesting work based on the new data } catch (err) { logger.error(`An error occurred ${err}`); throw err; } logger.info(`Successfully processed ${event.Records.length} records.`); } }; async function getRecordDataAsync( payload: KinesisStreamRecordPayload ): Promise<string> { var data = Buffer.from(payload.data, "base64").toString("utf-8"); await Promise.resolve(1); //Placeholder for actual async work return data; }
以下代码示例演示如何实现 Lambda 函数,该函数接收通过从 DynamoDB 流接收记录而触发的事件。该函数检索 DynamoDB 有效负载,并记录下记录内容。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 使用一个 DynamoDB 事件。 JavaScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 exports.handler = async (event, context) => { console.log(JSON.stringify(event, null, 2)); event.Records.forEach(record => { logDynamoDBRecord(record); }); }; const logDynamoDBRecord = (record) => { console.log(record.eventID); console.log(record.eventName); console.log(`DynamoDB Record: ${JSON.stringify(record.dynamodb)}`); };
使用 Lambda 使用一个 DynamoDB 事件。 TypeScript
export const handler = async (event, context) => { console.log(JSON.stringify(event, null, 2)); event.Records.forEach(record => { logDynamoDBRecord(record); }); } const logDynamoDBRecord = (record) => { console.log(record.eventID); console.log(record.eventName); console.log(`DynamoDB Record: ${JSON.stringify(record.dynamodb)}`); };
以下代码示例说明如何实现一个 Lambda 函数,该函数接收通过从 DocumentDB 更改流接收记录而触发的事件。该函数检索 DocumentDB 有效负载,并记录下记录内容。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 使用亚马逊 DocumentDB 事件。 JavaScript
console.log('Loading function'); exports.handler = async (event, context) => { event.events.forEach(record => { logDocumentDBEvent(record); }); return 'OK'; }; const logDocumentDBEvent = (record) => { console.log('Operation type: ' + record.event.operationType); console.log('db: ' + record.event.ns.db); console.log('collection: ' + record.event.ns.coll); console.log('Full document:', JSON.stringify(record.event.fullDocument, null, 2)); };
使用 Lambda 使用亚马逊文档数据库事件 TypeScript
import { DocumentDBEventRecord, DocumentDBEventSubscriptionContext } from 'aws-lambda'; console.log('Loading function'); export const handler = async ( event: DocumentDBEventSubscriptionContext, context: any ): Promise<string> => { event.events.forEach((record: DocumentDBEventRecord) => { logDocumentDBEvent(record); }); return 'OK'; }; const logDocumentDBEvent = (record: DocumentDBEventRecord): void => { console.log('Operation type: ' + record.event.operationType); console.log('db: ' + record.event.ns.db); console.log('collection: ' + record.event.ns.coll); console.log('Full document:', JSON.stringify(record.event.fullDocument, null, 2)); };
以下代码示例说明如何实现 Lambda 函数,该函数接收通过从 Ama MSK zon 集群接收记录而触发的事件。该函数检索MSK有效载荷并记录记录内容。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 使用亚马逊MSK活动。 JavaScript
exports.handler = async (event) => { // Iterate through keys for (let key in event.records) { console.log('Key: ', key) // Iterate through records event.records[key].map((record) => { console.log('Record: ', record) // Decode base64 const msg = Buffer.from(record.value, 'base64').toString() console.log('Message:', msg) }) } }
以下代码示例展示了如何实现一个 Lambda 函数,该函数接收通过将对象上传到 S3 桶而触发的事件。该函数从事件参数中检索 S3 存储桶名称和对象密钥,并调用 Amazon S3 API 来检索和记录对象的内容类型。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 使用 S3 事件。 JavaScript
import { S3Client, HeadObjectCommand } from "@aws-sdk/client-s3"; const client = new S3Client(); export const handler = async (event, context) => { // Get the object from the event and show its content type const bucket = event.Records[0].s3.bucket.name; const key = decodeURIComponent(event.Records[0].s3.object.key.replace(/\+/g, ' ')); try { const { ContentType } = await client.send(new HeadObjectCommand({ Bucket: bucket, Key: key, })); console.log('CONTENT TYPE:', ContentType); return ContentType; } catch (err) { console.log(err); const message = `Error getting object ${key} from bucket ${bucket}. Make sure they exist and your bucket is in the same region as this function.`; console.log(message); throw new Error(message); } };
使用 Lambda 使用 S3 事件。 TypeScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 import { S3Event } from 'aws-lambda'; import { S3Client, HeadObjectCommand } from '@aws-sdk/client-s3'; const s3 = new S3Client({ region: process.env.AWS_REGION }); export const handler = async (event: S3Event): Promise<string | undefined> => { // Get the object from the event and show its content type const bucket = event.Records[0].s3.bucket.name; const key = decodeURIComponent(event.Records[0].s3.object.key.replace(/\+/g, ' ')); const params = { Bucket: bucket, Key: key, }; try { const { ContentType } = await s3.send(new HeadObjectCommand(params)); console.log('CONTENT TYPE:', ContentType); return ContentType; } catch (err) { console.log(err); const message = `Error getting object ${key} from bucket ${bucket}. Make sure they exist and your bucket is in the same region as this function.`; console.log(message); throw new Error(message); } };
以下代码示例说明如何实现一个 Lambda 函数,该函数接收通过接收来自主题的消息而触发的事件。SNS该函数从事件参数检索消息并记录每条消息的内容。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 使用一个SNS事件。 JavaScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 exports.handler = async (event, context) => { for (const record of event.Records) { await processMessageAsync(record); } console.info("done"); }; async function processMessageAsync(record) { try { const message = JSON.stringify(record.Sns.Message); console.log(`Processed message ${message}`); await Promise.resolve(1); //Placeholder for actual async work } catch (err) { console.error("An error occurred"); throw err; } }
使用 Lambda 使用一个SNS事件。 TypeScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 import { SNSEvent, Context, SNSHandler, SNSEventRecord } from "aws-lambda"; export const functionHandler: SNSHandler = async ( event: SNSEvent, context: Context ): Promise<void> => { for (const record of event.Records) { await processMessageAsync(record); } console.info("done"); }; async function processMessageAsync(record: SNSEventRecord): Promise<any> { try { const message: string = JSON.stringify(record.Sns.Message); console.log(`Processed message ${message}`); await Promise.resolve(1); //Placeholder for actual async work } catch (err) { console.error("An error occurred"); throw err; } }
以下代码示例说明如何实现一个 Lambda 函数,该函数接收通过从队列接收消息而触发的事件。SQS该函数从事件参数检索消息并记录每条消息的内容。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 使用一个SQS事件。 JavaScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 exports.handler = async (event, context) => { for (const message of event.Records) { await processMessageAsync(message); } console.info("done"); }; async function processMessageAsync(message) { try { console.log(`Processed message ${message.body}`); // TODO: Do interesting work based on the new message await Promise.resolve(1); //Placeholder for actual async work } catch (err) { console.error("An error occurred"); throw err; } }
使用 Lambda 使用一个SQS事件。 TypeScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 import { SQSEvent, Context, SQSHandler, SQSRecord } from "aws-lambda"; export const functionHandler: SQSHandler = async ( event: SQSEvent, context: Context ): Promise<void> => { for (const message of event.Records) { await processMessageAsync(message); } console.info("done"); }; async function processMessageAsync(message: SQSRecord): Promise<any> { try { console.log(`Processed message ${message.body}`); // TODO: Do interesting work based on the new message await Promise.resolve(1); //Placeholder for actual async work } catch (err) { console.error("An error occurred"); throw err; } }
以下代码示例展示了如何为接收来自 Kinesis 流的事件的 Lambda 函数实现部分批处理响应。该函数在响应中报告批处理项目失败,并指示 Lambda 稍后重试这些消息。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 报告使用 Javascript 进行 Lambda Kinesis 批处理项目失败。
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 exports.handler = async (event, context) => { for (const record of event.Records) { try { console.log(`Processed Kinesis Event - EventID: ${record.eventID}`); const recordData = await getRecordDataAsync(record.kinesis); console.log(`Record Data: ${recordData}`); // TODO: Do interesting work based on the new data } catch (err) { console.error(`An error occurred ${err}`); /* Since we are working with streams, we can return the failed item immediately. Lambda will immediately begin to retry processing from this failed item onwards. */ return { batchItemFailures: [{ itemIdentifier: record.kinesis.sequenceNumber }], }; } } console.log(`Successfully processed ${event.Records.length} records.`); return { batchItemFailures: [] }; }; async function getRecordDataAsync(payload) { var data = Buffer.from(payload.data, "base64").toString("utf-8"); await Promise.resolve(1); //Placeholder for actual async work return data; }
使用 Lambda 报告 Kinesis 批处理项目失败。 TypeScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 import { KinesisStreamEvent, Context, KinesisStreamHandler, KinesisStreamRecordPayload, KinesisStreamBatchResponse, } from "aws-lambda"; import { Buffer } from "buffer"; import { Logger } from "@aws-lambda-powertools/logger"; const logger = new Logger({ logLevel: "INFO", serviceName: "kinesis-stream-handler-sample", }); export const functionHandler: KinesisStreamHandler = async ( event: KinesisStreamEvent, context: Context ): Promise<KinesisStreamBatchResponse> => { for (const record of event.Records) { try { logger.info(`Processed Kinesis Event - EventID: ${record.eventID}`); const recordData = await getRecordDataAsync(record.kinesis); logger.info(`Record Data: ${recordData}`); // TODO: Do interesting work based on the new data } catch (err) { logger.error(`An error occurred ${err}`); /* Since we are working with streams, we can return the failed item immediately. Lambda will immediately begin to retry processing from this failed item onwards. */ return { batchItemFailures: [{ itemIdentifier: record.kinesis.sequenceNumber }], }; } } logger.info(`Successfully processed ${event.Records.length} records.`); return { batchItemFailures: [] }; }; async function getRecordDataAsync( payload: KinesisStreamRecordPayload ): Promise<string> { var data = Buffer.from(payload.data, "base64").toString("utf-8"); await Promise.resolve(1); //Placeholder for actual async work return data; }
以下代码示例演示如何为接收来自 DynamoDB 流的事件的 Lambda 函数实现部分批量响应。该函数在响应中报告批处理项目失败,并指示 Lambda 稍后重试这些消息。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 报告 DynamoDB 批处理项目失败。 JavaScript
export const handler = async (event) => { const records = event.Records; let curRecordSequenceNumber = ""; for (const record of records) { try { // Process your record curRecordSequenceNumber = record.dynamodb.SequenceNumber; } catch (e) { // Return failed record's sequence number return { batchItemFailures: [{ itemIdentifier: curRecordSequenceNumber }] }; } } return { batchItemFailures: [] }; };
使用 Lambda 报告 DynamoDB 批处理项目失败。 TypeScript
import { DynamoDBBatchResponse, DynamoDBBatchItemFailure, DynamoDBStreamEvent, } from "aws-lambda"; export const handler = async ( event: DynamoDBStreamEvent ): Promise<DynamoDBBatchResponse> => { const batchItemFailures: DynamoDBBatchItemFailure[] = []; let curRecordSequenceNumber; for (const record of event.Records) { curRecordSequenceNumber = record.dynamodb?.SequenceNumber; if (curRecordSequenceNumber) { batchItemFailures.push({ itemIdentifier: curRecordSequenceNumber, }); } } return { batchItemFailures: batchItemFailures }; };
以下代码示例说明如何为从队列接收事件的 Lambda 函数实现部分批量响应。SQS该函数在响应中报告批处理项目失败,并指示 Lambda 稍后重试这些消息。
- SDK对于 JavaScript (v3)
-
注意
还有更多相关信息 GitHub。在无服务器示例
存储库中查找完整示例,并了解如何进行设置和运行。 使用 Lambda 报告SQS批量项目失败。 JavaScript
// Node.js 20.x Lambda runtime, AWS SDK for Javascript V3 export const handler = async (event, context) => { const batchItemFailures = []; for (const record of event.Records) { try { await processMessageAsync(record, context); } catch (error) { batchItemFailures.push({ itemIdentifier: record.messageId }); } } return { batchItemFailures }; }; async function processMessageAsync(record, context) { if (record.body && record.body.includes("error")) { throw new Error("There is an error in the SQS Message."); } console.log(`Processed message: ${record.body}`); }
使用 Lambda 报告SQS批量项目失败。 TypeScript
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 import { SQSEvent, SQSBatchResponse, Context, SQSBatchItemFailure, SQSRecord } from 'aws-lambda'; export const handler = async (event: SQSEvent, context: Context): Promise<SQSBatchResponse> => { const batchItemFailures: SQSBatchItemFailure[] = []; for (const record of event.Records) { try { await processMessageAsync(record); } catch (error) { batchItemFailures.push({ itemIdentifier: record.messageId }); } } return {batchItemFailures: batchItemFailures}; }; async function processMessageAsync(record: SQSRecord): Promise<void> { if (record.body && record.body.includes("error")) { throw new Error('There is an error in the SQS Message.'); } console.log(`Processed message ${record.body}`); }