AWS Cloudformation Dynamodb Agent Skill

AWS CloudFormation DynamoDB Patterns

Provides production-ready NoSQL database infrastructure patterns using AWS CloudFormation templates with DynamoDB tables, GSIs, LSIs, auto-scaling, encryption, TTL, and streams.

Overview

Covers DynamoDB tables, primary keys, secondary indexes (GSI/LSI), capacity modes, auto-scaling, encryption, TTL, streams, and best practices for parameters, outputs, and cross-stack references.

When to Use

Creating DynamoDB tables, configuring keys and indexes, setting capacity modes, implementing auto-scaling, enabling encryption/TTL/streams, and organizing CloudFormation templates.

Instructions

Follow these steps to create DynamoDB tables with CloudFormation:

• Define Table Parameters: Specify table name and billing mode
• Configure Primary Key: Set partition key and optional sort key
• Add Secondary Indexes: Create GSIs for alternative access patterns
• Configure Encryption: Enable encryption using KMS keys
• Set Up TTL: Define timestamp attribute for automatic deletion
• Enable Streams: Configure stream for change data capture
• Add Auto Scaling: Implement Application Auto Scaling for provisioned capacity
• Create Backup: Enable point-in-time recovery
• Validate Template: Run aws cloudformation validate-template before deployment

10. Deploy Stack: Use aws cloudformation create-stack or update-stack

11. Monitor Events: Check aws cloudformation describe-stack-events for failures or ROLLBACK status

12. Handle Rollback: On failure, review events for resource errors, fix the template, and re-deploy

Quick Reference

| Resource Type | Purpose |

|---------------|---------|

| AWS::DynamoDB::Table | Create DynamoDB table |

| AWS::ApplicationAutoScaling::ScalableTarget | Auto scaling configuration |

| AWS::ApplicationAutoScaling::ScalingPolicy | Scaling policies |

| AWS::KMS::Key | KMS key for encryption |

| AWS::IAM::Role | IAM roles for auto scaling |

| BillingMode | PAY_PER_REQUEST or PROVISIONED |

| SSESpecification | Server-side encryption |

Examples

Basic Table with On-Demand Capacity

DynamoDBTable:
  Type: AWS::DynamoDB::Table
  Properties:
    TableName: !Sub "${AWS::StackName}-table"
    BillingMode: PAY_PER_REQUEST
    AttributeDefinitions:
      - AttributeName: pk
        AttributeType: S
    KeySchema:
      - AttributeName: pk
        KeyType: HASH

Table with Global Secondary Index

DynamoDBTable:
  Type: AWS::DynamoDB::Table
  Properties:
    TableName: !Sub "${AWS::StackName}-table"
    BillingMode: PAY_PER_REQUEST
    AttributeDefinitions:
      - AttributeName: pk
        AttributeType: S
      - AttributeName: gsi-pk
        AttributeType: S
    KeySchema:
      - AttributeName: pk
        KeyType: HASH
    GlobalSecondaryIndexes:
      - IndexName: gsi-index
        KeySchema:
          - AttributeName: gsi-pk
            KeyType: HASH
        Projection:
          ProjectionType: ALL

Table with TTL

SessionTable:
  Type: AWS::DynamoDB::Table
  Properties:
    TableName: !Sub "${AWS::StackName}-sessions"
    BillingMode: PAY_PER_REQUEST
    AttributeDefinitions:
      - AttributeName: sessionId
        AttributeType: S
    KeySchema:
      - AttributeName: sessionId
        KeyType: HASH
    TimeToLiveSpecification:
      AttributeName: expiresAt
      Enabled: true

Table with Auto Scaling

ScalableTarget:
  Type: AWS::ApplicationAutoScaling::ScalableTarget
  Properties:
    MaxCapacity: 100
    MinCapacity: 5
    ResourceId: !Sub "table/${DynamoDBTable}"
    RoleARN: !GetAtt AutoScalingRole.Arn
    ScalableDimension: dynamodb:table:ReadCapacityUnits
    ServiceNamespace: dynamodb

See references/complete-examples.md for more complete examples including encryption, streams, auto scaling, and production tables.

Template Structure

Base Template

AWSTemplateFormatVersion: 2010-09-09
Description: DynamoDB table with GSI and auto-scaling

Parameters:
  TableName:
    Type: String
    Default: my-table
  BillingMode:
    Type: String
    Default: PAY_PER_REQUEST

Resources:
  DynamoDBTable:
    Type: AWS::DynamoDB::Table
    Properties:
      TableName: !Ref TableName
      BillingMode: !Ref BillingMode

Outputs:
  TableName:
    Value: !Ref DynamoDBTable
  TableArn:
    Value: !GetAtt DynamoDBTable.Arn

See references/advanced-configuration.md for detailed Parameters, Mappings, Conditions, Outputs, IAM roles, and cross-stack references.

Best Practices

• Use PAY_PER_REQUEST for development/testing and unpredictable workloads
• Enable Point-In-Time Recovery for production tables
• Use KMS encryption for sensitive data (SSE-KMS)
• Configure auto-scaling for provisioned capacity tables
• Design GSIs carefully - each GSI consumes capacity
• Use TTL for automatic data expiration (sessions, cache)
• Enable Streams for change data capture and analytics
• Tag resources for cost allocation and organization
• Export outputs for cross-stack references

10. Use Conditions for environment-specific configurations

Common Troubleshooting

Table already exists: Use unique table names or stack deletion policy

GSI creation fails: Verify attribute definitions include GSI attributes

Auto-scaling not working: Check IAM role permissions and service-linked role

TTL not expiring: Ensure TTL attribute is Number type, not String

Streams not enabled: Can only enable streams during table creation

Encryption errors: Verify KMS key exists in same region as table

Related Skills

• aws-cloudformation-security - Security best practices for DynamoDB
• aws-cloudformation-lambda - Lambda triggers for DynamoDB Streams
• aws-cloudformation-iam - IAM roles for DynamoDB access

References

Complete Examples

• references/complete-examples.md - Basic tables, GSI, LSI, TTL, encryption, PITR, auto-scaling, production tables, global tables, streams

Advanced Configuration

• references/advanced-configuration.md - Parameters, Mappings, Conditions, auto scaling policies, streams, TTL, global tables, outputs, IAM roles, deletion policies

Constraints and Warnings

• Table names: Must be unique per region (globally unique for global tables)
• GSI limits: Maximum 5 GSIs per table (for single-region tables)
• LSI limits: Maximum 5 LSIs per table, same partition key as table
• Capacity limits: On-demand has default account limits (40,000 RCUs, 40,000 WCUs)
• Auto-scaling: Requires PROVISIONED billing mode (not PAY_PER_REQUEST)
• Point-in-time recovery: Can only be enabled during table creation
• Streams: Can only be enabled during table creation
• Encryption: KMS keys must be in same region as table
• TTL: Attribute must be Number type, measured in seconds
• Throughput: Each GSI shares provisioned throughput with table
• Item size limit: Maximum 400 KB per item
• Hot partition: Design keys to avoid hot partition issues