serverless.yml

service:
  name: moneybutton-webhook-proxy

# Add the serverless-webpack plugin
plugins:
  - serverless-webpack
  - serverless-offline-sns
  - serverless-offline
provider:
  name: aws
  runtime: nodejs10.x
  region: ${opt:region, 'ap-southeast-1'}
  memorySize: 128
  usagePlan:
    rateLimit: ${opt:rateLimit,'2'}
    burstLimit: ${opt:burstLimit,'8'}
  iamRoleStatements:
    - Effect: 'Allow'
      Action:
        - 'sns:Publish'
      Resource:
        Ref: WebhookNotificationTopic


custom:
  webpack:
    includeModules: true
    keepOutputDirectory: true
  serverless-offline-sns:
    port: 4002
    debug: true

functions:
  webhook:
    handler: src/functions/webhook.handle
    environment:
      TOPIC_ARN:
        Ref: WebhookNotificationTopic
      WEBHOOK_SECRET: ${ssm:moneybuttonWebhookProxySecret}

    events:
      - http:
          method: post
          path: webhook
  processSNSMessage:
    handler: src/functions/processSNSMessage.middyHandler
    environment:
      TARGET_ENDPOINT: ${opt:targetEndpoint}
      REQUEST_TIMOUT: ${opt:endpointTimeout,'5000'}
      TOPIC_ARN:
        Ref: WebhookNotificationTopic
    events:
      - http:
          method: post
          path: processSNSMessage


resources:
  Resources:
    WebhookNotificationTopic:
      Type: AWS::SNS::Topic
      Properties:
        DisplayName: 'Topic for delivery of webhook notifications to target endpoint'
    ProcessMessageSubscription:
      Type: AWS::SNS::Subscription
      Properties:
        Protocol: 'https'
        DeliveryPolicy: "{\"healthyRetryPolicy\":{\"minDelayTarget\":${env:SNS_MIN_DELAY,'120'},\"maxDelayTarget\":${env:SNS_MAX_DELAY,'600'},\"numRetries\":11,\"numMaxDelayRetries\":${env:POST_BACKOFF_RETRIES,'2'},\"numNoDelayRetries\": ${env:IMMEDIATE_RETRIES,'1'},\"numMinDelayRetries\": ${env:PRE_BACKOFF_RETRIES,'2'},\"backoffFunction\":\"exponential\"}}"
        TopicArn:
          Ref: WebhookNotificationTopic
        Endpoint:
          Fn::Join:
            - ""
            - - "https://"
              - Ref: "ApiGatewayRestApi"
              - ".execute-api.${self:provider.region}.amazonaws.com/${self:provider.stage}/processSNSMessage"
  Outputs:
    WebhookNotificationTopicARN:
      Description: ARN of WebhookNotificationTopic Endpoint
      Value:
        Ref: WebhookNotificationTopic