Description

DynamoDB local Streams for serverless-aws-lambda

Installation

yarn add -D serverless-aws-lambda-ddb-streams
# or
npm install -D serverless-aws-lambda-ddb-streams

Usage

use serverless-aws-lambda's defineConfig to import this plugin

// config.js
const { defineConfig } = require("serverless-aws-lambda/defineConfig");
const { dynamoStream } = require("serverless-aws-lambda-ddb-streams");

module.exports = defineConfig({
  plugins: [dynamoStream()],
});

Configuration

{
  endpoint?: string; // default "http://localhost:8000"
  region?: string; // based on your serverless.yml or default "eu-west-1"
  waitBeforeInit?: number; // default 25 (secondes)
  watchInterval?: number; // default 2 (secondes)
}

• endpoint:
  local DynamoDB http endpoint
• region: AWS Region for dynamodb client
• waitBeforeInit:
  An error will be thrown if after "waitBeforeInit" the plugin was not able to connect to the Table.
• watchInterval:
  interval to check for new streamable records.

example:

module.exports = defineConfig({
  plugins: [
    dynamoStream({
      endpoint: "http://localhost:8822",
      waitBeforeInit: 40,
    }),
  ],
});

# serverless.yml
service: sls-project

frameworkVersion: "3"

plugins:
  - serverless-aws-lambda

custom:
  serverless-aws-lambda:
    configPath: ./config.default

provider:
  name: aws
  runtime: nodejs18.x
  region: eu-west-3

functions:
  myAwsomeLambda:
    handler: src/handlers/lambda.default
    events:
      - stream:
          arn: arn:aws:dynamodb:region:XXXXXX:table/Banana/stream/1970-01-01T00:00:00.000
          batchSize: 3

Supported stream declarations

- stream:
    arn: arn:aws:dynamodb:region:XXXXXX:table/Banana/stream/1970-01-01T00:00:00.000

- stream:
    type: dynamodb
    arn:
      Fn::GetAtt: [MyDynamoDbTable, StreamArn]

- stream:
    arn:
      Fn::ImportValue: MyExportedDynamoDbStreamArnId

- stream:
    arn:
      Ref: MyDynamoDbTableStreamArn

- stream:
    arn: !GetAtt dynamoTable.StreamArn

functions:
  myAwsomeLambda:
    handler: src/handlers/lambda.default
    events:
      - stream:
          arn: arn:aws:dynamodb:region:XXXXXX:table/Banana/stream/1970-01-01T00:00:00.000
          batchSize: 3
          filterPatterns:
            - eventName: [INSERT]
            - dynamodb:
                NewImage:
                  OrderId:
                    N:
                      - numeric: [">", 4]

Supported configurations

✅ supported
🌕 planned
❌ not planned

• ✅ batchSize
• ✅ batchWindow
• ✅ bisectBatchOnFunctionError
• ✅ destinations (requires AWS Local SNS and/or AWS Local SQS)
• ✅ enabled
• ✅ filterPatterns
• ✅ functionResponseType
• ✅ maximumRecordAgeInSeconds
• ✅ maximumRetryAttempts
• ❌ startingPosition (uses always "LATEST")
• ❌ startingPositionTimestamp
• ✅ tumblingWindowInSeconds
• ❌ parallelizationFactor