DynamoDB

A leaky bucket backed by AWS DynamoDB

Usage

This library assumes the table is created with the following attributes:

• name is the primary key
• (optional) _ttl is the enabled time to live specification field

Depending on your use case it may be worth disabling the default retries in the passed in aws.Config object. Please refer to the following sections for examples.

CloudFormation Table Definition Example

  Buckets:
    Type: AWS::DynamoDB::Table
    Properties:
      AttributeDefinitions:
      - AttributeName: name
        AttributeType: S
      BillingMode: PAY_PER_REQUEST
      KeySchema:
      - AttributeName: name
        KeyType: HASH
      SSESpecification:
        SSEEnabled: true
      TableName: your-favorite-table-naming-strategy-Buckets
      TimeToLiveSpecification:
        AttributeName: _ttl
        Enabled: true

Usage Example

package main

import (
    "log"
    "time"

    leakybucketDynamoDB "github.com/Clever/leakybucket/dynamodb"

    "github.com/aws/aws-sdk-go/aws"
    "github.com/aws/aws-sdk-go/aws/session"
)

func main() {
    storage, err := leakybucketDynamoDB.New(
        "buckets-table",
        session.New(&aws.Config{
            Region:     aws.String("us-west-1"),
            MaxRetries: aws.Int(0),
        }),
        24*time.Hour,
    )
    if err != nil {
        log.Fatal(err)
    }

    bucket, err := storage.Create("my-bucket", 100, time.Minute)
    if err != nil {
        log.Fatal(err)
    }

    // use your new leaky bucket!
}

Testing

All tests assume there is a locally running DynamoDB defined in an environment variable AWS_DYNAMO_ENDPOINT

Helpful Development Resources

• DynamoDB CloudFormation User Guide
• DynamoDB Conditional Expressions
• DynamoDB Update Expressions