Criar um item do DynamoDB com TTL usando um SDK da AWS

Os exemplos de código a seguir mostram como criar um item com TTL.

Java

SDK para Java 2.x

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0

package com.amazon.samplelib.ttl;

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
import software.amazon.awssdk.services.dynamodb.model.DynamoDbException;
import software.amazon.awssdk.services.dynamodb.model.PutItemRequest;
import software.amazon.awssdk.services.dynamodb.model.PutItemResponse;
import software.amazon.awssdk.services.dynamodb.model.ResourceNotFoundException;
import software.amazon.awssdk.utils.ImmutableMap;

import java.io.Serializable;
import java.util.Map;
import java.util.Optional;

public class CreateTTL {
    public static void main(String[] args) {
        final String usage = """
                Usage:
                    <tableName> <primaryKey> <sortKey> <region>
                Where:
                    tableName - The Amazon DynamoDB table being queried.
                    primaryKey - The name of the primary key. Also known as the hash or partition key.
                    sortKey - The name of the sort key. Also known as the range attribute.
                    region (optional) - The AWS region that the Amazon DynamoDB table is located in. (Default: us-east-1)
                """;
        // Optional "region" parameter - if args list length is NOT 3 or 4, short-circuit exit.
        if (!(args.length == 3 || args.length == 4)) {
            System.out.println(usage);
            System.exit(1);
        }

        String tableName = args[0];
        String primaryKey = args[1];
        String sortKey = args[2];
        Region region = Optional.ofNullable(args[3]).isEmpty() ? Region.US_EAST_1 : Region.of(args[3]);

        // Get current time in epoch second format
        final long createDate = System.currentTimeMillis() / 1000;

        // Calculate expiration time 90 days from now in epoch second format
        final long expireDate = createDate + (90 * 24 * 60 * 60);

        final ImmutableMap<String, ? extends Serializable> itemMap =
                ImmutableMap.of("primaryKey", primaryKey,
                "sortKey", sortKey,
                "creationDate", createDate,
                "expireAt", expireDate);
        final PutItemRequest request = PutItemRequest.builder()
                .tableName(tableName)
                .item((Map<String, AttributeValue>) itemMap)
                .build();
        try (DynamoDbClient ddb = DynamoDbClient.builder()
                .region(region)
                .build()) {
            final PutItemResponse response = ddb.putItem(request);
            System.out.println(tableName + " PutItem operation with TTL successful. Request id is "
                    + response.responseMetadata().requestId());
        } catch (ResourceNotFoundException e) {
            System.err.format("Error: The Amazon DynamoDB table \"%s\" can't be found.\n", tableName);
            System.exit(1);
        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
        System.exit(0);
    }
}

• Para obter detalhes da API, consulte PutItem na Referência da API AWS SDK for Java 2.x.

JavaScript

SDK para JavaScript (v3)

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
import { DynamoDBClient, PutItemCommand } from "@aws-sdk/client-dynamodb";

function createDynamoDBItem(table_name, region, partition_key, sort_key) {
    const client = new DynamoDBClient({
        region: region,
        endpoint: `https://dynamodb.${region}.amazonaws.com`
    });

    // Get the current time in epoch second format
    const current_time = Math.floor(new Date().getTime() / 1000);

    // Calculate the expireAt time (90 days from now) in epoch second format
    const expire_at = Math.floor((new Date().getTime() + 90 * 24 * 60 * 60 * 1000) / 1000);

    // Create DynamoDB item
    const item = {
        'partitionKey': {'S': partition_key},
        'sortKey': {'S': sort_key},
        'createdAt': {'N': current_time.toString()},
        'expireAt': {'N': expire_at.toString()}
    };

    const putItemCommand = new PutItemCommand({
        TableName: table_name,
        Item: item,
        ProvisionedThroughput: {
            ReadCapacityUnits: 1,
            WriteCapacityUnits: 1,
        },
    });

    client.send(putItemCommand, function(err, data) {
        if (err) {
            console.log("Exception encountered when creating item %s, here's what happened: ", data, ex);
            throw err;
        } else {
            console.log("Item created successfully: %s.", data);
            return data;
        }
    });
}

// use your own values
createDynamoDBItem('your-table-name', 'us-east-1', 'your-partition-key-value', 'your-sort-key-value');

• Para obter detalhes da API, consulte PutItem na Referência da API AWS SDK for JavaScript.

Python

SDK para Python (Boto3)

# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: Apache-2.0
import boto3
from datetime import datetime, timedelta

def create_dynamodb_item(table_name, region, primary_key, sort_key):
    """
    Creates a DynamoDB item with an attached expiry attribute.

    :param table_name: Table name for the boto3 resource to target when creating an item
    :param region: string representing the AWS region. Example: `us-east-1`
    :param primary_key: one attribute known as the partition key.
    :param sort_key: Also known as a range attribute.
    :return: Void (nothing)
    """
    try:
        dynamodb = boto3.resource('dynamodb', region_name=region)
        table = dynamodb.Table(table_name)

        # Get the current time in epoch second format
        current_time = int(datetime.now().timestamp())

        # Calculate the expiration time (90 days from now) in epoch second format
        expiration_time = int((datetime.now() + timedelta(days=90)).timestamp())

        item = {
            'primaryKey': primary_key,
            'sortKey': sort_key,
            'creationDate': current_time,
            'expireAt': expiration_time
        }

        table.put_item(Item=item)

        print("Item created successfully.")
    except Exception as e:
        print(f"Error creating item: {e}")
        raise


# Use your own values
create_dynamodb_item('your-table-name', 'us-west-2', 'your-partition-key-value', 'your-sort-key-value')

• Para obter detalhes da API, consulte PutItem na Referência da API AWS SDK para Python (Boto3).

Para ver uma lista completa dos Guias do desenvolvedor de SDK da AWS e exemplos de código, consulte Usar o DynamoDB com um AWS SDK. Este tópico também inclui informações sobre como começar e detalhes sobre versões anteriores do SDK.