Strapi Serverless config with S3 static bucket.

serverless.yml

service: sls-strapi

provider:
  name: aws
  runtime: nodejs12.x
  profile: <your-aws-profile>
  logRetentionInDays: ${self:custom.vars.logRetentionInDays, 1}

  environment:
    ADMIN_JWT_SECRET: "Just using dummy"
    API_SERVICE_HOST: "https://l4rjveb7rk.execute-api.us-east-1.amazonaws.com/dev"
    BUCKET_NAME: !Ref S3StaticBucket
    # URL from a free Mongo Atlas cluster.
    MONGODB_URI: "mongodb+srv://strapiowner:PASSWORD@cluster0.weldo.mongodb.net/strapi?retryWrites=true&w=majority"
  
  iamRoleStatements:
    - Effect: Allow
      Action: 
        - "s3:*"
      Resource: 
        - !Sub 
          - "#{BucketArn}/*"
          - BucketArn: !GetAtt S3StaticBucket.Arn
        - !GetAtt S3StaticBucket.Arn

resources:
  Resources:  
    S3StaticBucket:
      Type: AWS::S3::Bucket
      
custom:
  apigwBinary:
    types:
      - "multipart/form-data"

plugins:
  - serverless-offline
  - serverless-cloudformation-sub-variables
  - serverless-apigw-binary

# ...