serverless.yml

service: thumbnailer-service # NOTE: update this with your service name
plugins:
  - serverless-offline
  - serverless-plugin-existing-s3
provider:
  name: aws
  stage: dev
  region: us-east-1
  profile: default
  runtime: nodejs6.10
  memorySize: 256
  timeout: 30
  iamRoleStatements:
    - Effect: "Allow"
      Action:
        - "sns:*"
      Resource: "*"
    - Effect: "Allow"
      Action:
        - "s3:*"
      Resource:
       Fn::Join:
        - ""
        - - "*"
functions:
  thumbnailer:
    handler: index.thumbnailer
    events:
      - s3:
          bucket: <your-bucket-name>
          event: s3:ObjectCreated:*
          rules:
            - prefix: <folder-name>/