通过 Amazon DocumentDB 触发器调用 Lambda 函数 - Amazon Lambda
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通过 Amazon DocumentDB 触发器调用 Lambda 函数

以下代码示例演示了如何实现一个 Lambda 函数,该函数接收通过接收来自 DynamoDB 更改流的记录而触发的事件。该函数检索 DocumentDB 有效负载,并记录下记录内容。

.NET
Amazon SDK for .NET
注意

查看 GitHub,了解更多信息。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 .NET 将 Amazon DocumentDB 事件与 Lambda 结合使用。

using Amazon.Lambda.Core; using System.Text.Json; using System; using System.Collections.Generic; using System.Text.Json.Serialization; //Assembly attribute to enable the Lambda function's JSON input to be converted into a .NET class. [assembly: LambdaSerializer(typeof(Amazon.Lambda.Serialization.SystemTextJson.DefaultLambdaJsonSerializer))] namespace LambdaDocDb; public class Function { /// <summary> /// Lambda function entry point to process Amazon DocumentDB events. /// </summary> /// <param name="event">The Amazon DocumentDB event.</param> /// <param name="context">The Lambda context object.</param> /// <returns>A string to indicate successful processing.</returns> public string FunctionHandler(Event evnt, ILambdaContext context) { foreach (var record in evnt.Events) { ProcessDocumentDBEvent(record, context); } return "OK"; } private void ProcessDocumentDBEvent(DocumentDBEventRecord record, ILambdaContext context) { var eventData = record.Event; var operationType = eventData.OperationType; var databaseName = eventData.Ns.Db; var collectionName = eventData.Ns.Coll; var fullDocument = JsonSerializer.Serialize(eventData.FullDocument, new JsonSerializerOptions { WriteIndented = true }); context.Logger.LogLine($"Operation type: {operationType}"); context.Logger.LogLine($"Database: {databaseName}"); context.Logger.LogLine($"Collection: {collectionName}"); context.Logger.LogLine($"Full document:\n{fullDocument}"); } public class Event { [JsonPropertyName("eventSourceArn")] public string EventSourceArn { get; set; } [JsonPropertyName("events")] public List<DocumentDBEventRecord> Events { get; set; } [JsonPropertyName("eventSource")] public string EventSource { get; set; } } public class DocumentDBEventRecord { [JsonPropertyName("event")] public EventData Event { get; set; } } public class EventData { [JsonPropertyName("_id")] public IdData Id { get; set; } [JsonPropertyName("clusterTime")] public ClusterTime ClusterTime { get; set; } [JsonPropertyName("documentKey")] public DocumentKey DocumentKey { get; set; } [JsonPropertyName("fullDocument")] public Dictionary<string, object> FullDocument { get; set; } [JsonPropertyName("ns")] public Namespace Ns { get; set; } [JsonPropertyName("operationType")] public string OperationType { get; set; } } public class IdData { [JsonPropertyName("_data")] public string Data { get; set; } } public class ClusterTime { [JsonPropertyName("$timestamp")] public Timestamp Timestamp { get; set; } } public class Timestamp { [JsonPropertyName("t")] public long T { get; set; } [JsonPropertyName("i")] public int I { get; set; } } public class DocumentKey { [JsonPropertyName("_id")] public Id Id { get; set; } } public class Id { [JsonPropertyName("$oid")] public string Oid { get; set; } } public class Namespace { [JsonPropertyName("db")] public string Db { get; set; } [JsonPropertyName("coll")] public string Coll { get; set; } } }
Go
适用于 Go V2 的 SDK
注意

查看 GitHub,了解更多信息。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 Go 将 Amazon DocumentDB 事件与 Lambda 结合使用。

package main import ( "context" "encoding/json" "fmt" "github.com/aws/aws-lambda-go/lambda" ) type Event struct { Events []Record `json:"events"` } type Record struct { Event struct { OperationType string `json:"operationType"` NS struct { DB string `json:"db"` Coll string `json:"coll"` } `json:"ns"` FullDocument interface{} `json:"fullDocument"` } `json:"event"` } func main() { lambda.Start(handler) } func handler(ctx context.Context, event Event) (string, error) { fmt.Println("Loading function") for _, record := range event.Events { logDocumentDBEvent(record) } return "OK", nil } func logDocumentDBEvent(record Record) { fmt.Printf("Operation type: %s\n", record.Event.OperationType) fmt.Printf("db: %s\n", record.Event.NS.DB) fmt.Printf("collection: %s\n", record.Event.NS.Coll) docBytes, _ := json.MarshalIndent(record.Event.FullDocument, "", " ") fmt.Printf("Full document: %s\n", string(docBytes)) }
Java
适用于 Java 的 SDK 2.x
注意

查看 GitHub,了解更多信息。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 Java 将 Amazon DocumentDB 事件与 Lambda 结合使用。

import java.util.List; import java.util.Map; import com.amazonaws.services.lambda.runtime.Context; import com.amazonaws.services.lambda.runtime.RequestHandler; public class Example implements RequestHandler<Map<String, Object>, String> { @SuppressWarnings("unchecked") @Override public String handleRequest(Map<String, Object> event, Context context) { List<Map<String, Object>> events = (List<Map<String, Object>>) event.get("events"); for (Map<String, Object> record : events) { Map<String, Object> eventData = (Map<String, Object>) record.get("event"); processEventData(eventData); } return "OK"; } @SuppressWarnings("unchecked") private void processEventData(Map<String, Object> eventData) { String operationType = (String) eventData.get("operationType"); System.out.println("operationType: %s".formatted(operationType)); Map<String, Object> ns = (Map<String, Object>) eventData.get("ns"); String db = (String) ns.get("db"); System.out.println("db: %s".formatted(db)); String coll = (String) ns.get("coll"); System.out.println("coll: %s".formatted(coll)); Map<String, Object> fullDocument = (Map<String, Object>) eventData.get("fullDocument"); System.out.println("fullDocument: %s".formatted(fullDocument)); } }
JavaScript
适用于 JavaScript 的 SDK(v3)
注意

查看 GitHub,了解更多信息。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 JavaScript 将 Amazon DocumentDB 事件与 Lambda 结合使用。

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 TypeScript 将 Amazon DocumentDB 事件与 Lambda 结合使用

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)); };
PHP
适用于 PHP 的 SDK
注意

查看 GitHub,了解更多信息。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 PHP 将 Amazon DocumentDB 事件与 Lambda 结合使用。

<?php require __DIR__.'/vendor/autoload.php'; use Bref\Context\Context; use Bref\Event\Handler; class DocumentDBEventHandler implements Handler { public function handle($event, Context $context): string { $events = $event['events'] ?? []; foreach ($events as $record) { $this->logDocumentDBEvent($record['event']); } return 'OK'; } private function logDocumentDBEvent($event): void { // Extract information from the event record $operationType = $event['operationType'] ?? 'Unknown'; $db = $event['ns']['db'] ?? 'Unknown'; $collection = $event['ns']['coll'] ?? 'Unknown'; $fullDocument = $event['fullDocument'] ?? []; // Log the event details echo "Operation type: $operationType\n"; echo "Database: $db\n"; echo "Collection: $collection\n"; echo "Full document: " . json_encode($fullDocument, JSON_PRETTY_PRINT) . "\n"; } } return new DocumentDBEventHandler();
Python
适用于 Python 的 SDK(Boto3)
注意

查看 GitHub,了解更多信息。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 Python 将 Amazon DocumentDB 事件与 Lambda 结合使用。

import json def lambda_handler(event, context): for record in event.get('events', []): log_document_db_event(record) return 'OK' def log_document_db_event(record): event_data = record.get('event', {}) operation_type = event_data.get('operationType', 'Unknown') db = event_data.get('ns', {}).get('db', 'Unknown') collection = event_data.get('ns', {}).get('coll', 'Unknown') full_document = event_data.get('fullDocument', {}) print(f"Operation type: {operation_type}") print(f"db: {db}") print(f"collection: {collection}") print("Full document:", json.dumps(full_document, indent=2))
Ruby
适用于 Ruby 的 SDK
注意

查看 GitHub,了解更多信息。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 Ruby 将 Amazon DocumentDB 事件与 Lambda 结合使用。

require 'json' def lambda_handler(event:, context:) event['events'].each do |record| log_document_db_event(record) end 'OK' end def log_document_db_event(record) event_data = record['event'] || {} operation_type = event_data['operationType'] || 'Unknown' db = event_data.dig('ns', 'db') || 'Unknown' collection = event_data.dig('ns', 'coll') || 'Unknown' full_document = event_data['fullDocument'] || {} puts "Operation type: #{operation_type}" puts "db: #{db}" puts "collection: #{collection}" puts "Full document: #{JSON.pretty_generate(full_document)}" end
Rust
适用于 Rust 的 SDK
注意

查看 GitHub,了解更多信息。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 Rust 将 Amazon DocumentDB 事件与 Lambda 结合使用。

use lambda_runtime::{service_fn, tracing, Error, LambdaEvent}; use aws_lambda_events::{ event::documentdb::{DocumentDbEvent, DocumentDbInnerEvent}, }; // Built with the following dependencies: //lambda_runtime = "0.11.1" //serde_json = "1.0" //tokio = { version = "1", features = ["macros"] } //tracing = { version = "0.1", features = ["log"] } //tracing-subscriber = { version = "0.3", default-features = false, features = ["fmt"] } //aws_lambda_events = "0.15.0" async fn function_handler(event: LambdaEvent<DocumentDbEvent>) ->Result<(), Error> { tracing::info!("Event Source ARN: {:?}", event.payload.event_source_arn); tracing::info!("Event Source: {:?}", event.payload.event_source); let records = &event.payload.events; if records.is_empty() { tracing::info!("No records found. Exiting."); return Ok(()); } for record in records{ log_document_db_event(record); } tracing::info!("Document db records processed"); // Prepare the response Ok(()) } fn log_document_db_event(record: &DocumentDbInnerEvent)-> Result<(), Error>{ tracing::info!("Change Event: {:?}", record.event); Ok(()) } #[tokio::main] async fn main() -> Result<(), Error> { tracing_subscriber::fmt() .with_max_level(tracing::Level::INFO) .with_target(false) .without_time() .init(); let func = service_fn(function_handler); lambda_runtime::run(func).await?; Ok(()) }

有关 Amazon SDK 开发人员指南和代码示例的完整列表,请参阅 将 Lambda 与 Amazon SDK 配合使用。本主题还包括有关入门的信息以及有关先前的 SDK 版本的详细信息。