# Trabalho com os fluxos e com a vida útil do DynamoDB usando a versão 2 da AWS Command Line Interface
<a name="iam_example_dynamodb_Scenario_StreamsAndTTL_section"></a>

O exemplo de código apresentado a seguir demonstra como gerenciar os recursos de fluxos e de vida útil do DynamoDB.
+ Crie uma tabela com a opção de fluxos habilitada.
+ Descreva os fluxos.
+ Crie uma função do Lambda para processar os fluxos.
+ Habilite a vida útil (TTL) em uma tabela.
+ Adicione itens com atributos de TTL.
+ Descreva as configurações de TTL.

------
#### [ Bash ]

**AWS CLI com script Bash**  
Crie uma tabela com a opção de fluxos habilitada.  

```
# Create a table with DynamoDB Streams enabled
aws dynamodb create-table \
    --table-name StreamsDemo \
    --attribute-definitions \
        AttributeName=ID,AttributeType=S \
    --key-schema \
        AttributeName=ID,KeyType=HASH \
    --billing-mode PAY_PER_REQUEST \
    --stream-specification StreamEnabled=true,StreamViewType=NEW_AND_OLD_IMAGES
```
Descreva os fluxos.  

```
# Get information about the stream
aws dynamodb describe-table \
    --table-name StreamsDemo \
    --query "Table.StreamSpecification"

# Get the stream ARN
STREAM_ARN=$(aws dynamodb describe-table \
    --table-name StreamsDemo \
    --query "Table.LatestStreamArn" \
    --output text)

echo "Stream ARN: $STREAM_ARN"

# Describe the stream
aws dynamodbstreams describe-stream \
    --stream-arn $STREAM_ARN
```
Crie uma função do Lambda para os fluxos.  

```
# Step 1: Create an IAM role for the Lambda function
cat > trust-policy.json << 'EOF'
{
  "Version":"2012-10-17",		 	 	 
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": "lambda.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}
EOF

aws iam create-role \
    --role-name DynamoDBStreamsLambdaRole \
    --assume-role-policy-document file://trust-policy.json

# Step 2: Attach permissions to the role
aws iam attach-role-policy \
    --role-name DynamoDBStreamsLambdaRole \
    --policy-arn arn:aws:iam::aws:policy/service-role/AWSLambdaDynamoDBExecutionRole

# Step 3: Create a Lambda function (code would be in a separate file)
echo "Lambda function creation would be done separately with appropriate code"

# Step 4: Create an event source mapping
echo "Example command to create event source mapping:"
echo "aws lambda create-event-source-mapping \\"
echo "    --function-name ProcessDynamoDBRecords \\"
echo "    --event-source $STREAM_ARN \\"
echo "    --batch-size 100 \\"
echo "    --starting-position LATEST"
```
Habilite a vida útil (TTL) em uma tabela.  

```
# Create a table for TTL demonstration
aws dynamodb create-table \
    --table-name TTLDemo \
    --attribute-definitions \
        AttributeName=ID,AttributeType=S \
    --key-schema \
        AttributeName=ID,KeyType=HASH \
    --billing-mode PAY_PER_REQUEST

# Wait for table to become active
aws dynamodb wait table-exists --table-name TTLDemo

# Enable TTL on the table
aws dynamodb update-time-to-live \
    --table-name TTLDemo \
    --time-to-live-specification "Enabled=true, AttributeName=ExpirationTime"
```
Adicione itens com atributos de TTL.  

```
# Calculate expiration time (current time + 1 day in seconds)
EXPIRATION_TIME=$(date -d "+1 day" +%s)

# Add an item with TTL attribute
aws dynamodb put-item \
    --table-name TTLDemo \
    --item '{
        "ID": {"S": "item1"},
        "Data": {"S": "This item will expire in 1 day"},
        "ExpirationTime": {"N": "'$EXPIRATION_TIME'"}
    }'

# Add an item that expires in 1 hour
EXPIRATION_TIME_HOUR=$(date -d "+1 hour" +%s)
aws dynamodb put-item \
    --table-name TTLDemo \
    --item '{
        "ID": {"S": "item2"},
        "Data": {"S": "This item will expire in 1 hour"},
        "ExpirationTime": {"N": "'$EXPIRATION_TIME_HOUR'"}
    }'
```
Descreva as configurações de TTL.  

```
# Describe TTL settings for a table
aws dynamodb describe-time-to-live \
    --table-name TTLDemo
```
+ Consulte detalhes da API nos tópicos a seguir na *Referência de comandos da AWS CLI*.
  + [AttachRolePolicy](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/AttachRolePolicy)
  + [CreateRole](https://docs.aws.amazon.com/goto/aws-cli/iam-2010-05-08/CreateRole)
  + [CreateTable](https://docs.aws.amazon.com/goto/aws-cli/dynamodb-2012-08-10/CreateTable)
  + [DescribeTable](https://docs.aws.amazon.com/goto/aws-cli/dynamodb-2012-08-10/DescribeTable)
  + [DescribeTimeToLive](https://docs.aws.amazon.com/goto/aws-cli/dynamodb-2012-08-10/DescribeTimeToLive)
  + [PutItem](https://docs.aws.amazon.com/goto/aws-cli/dynamodb-2012-08-10/PutItem)
  + [UpdateTimeToLive](https://docs.aws.amazon.com/goto/aws-cli/dynamodb-2012-08-10/UpdateTimeToLive)

------

Para ver uma lista completa dos guias de desenvolvedor e exemplos de código do SDK da AWS, consulte [Using this service with an AWS SDK](sdk-general-information-section.md). Este tópico também inclui informações sobre como começar e detalhes sobre versões anteriores do SDK.