How do you specify multiple functions to for a single bucket event with custom bucket configuration

Serverless Framework
1

Hello, from the example for an s3 event https://serverless.com/framework/docs/providers/aws/events/s3/ we have:

functions:
  resize:
    handler: resize.handler
    events:
      - s3: photos
resources:
  Resources:
    S3BucketPhotos:
      Type: AWS::S3::Bucket
      Properties:
        BucketName: my-custom-bucket-name
        # add additional custom bucket configuration here
    ResizeLambdaPermissionPhotosS3:
      Type: "AWS::Lambda::Permission"
      Properties:
        FunctionName:
          "Fn::GetAtt":
            - ResizeLambdaFunction
            - Arn
        Principal: "s3.amazonaws.com"
        Action: "lambda:InvokeFunction"
        SourceAccount:
          Ref: AWS::AccountId
        SourceArn: "arn:aws:s3:::my-custom-bucket-name"

this works, but how do you specify a a specific function per event, as per https://serverless.com/framework/docs/providers/aws/events/s3#triggering-separate-functions-from-the-same-bucket, but with custom bucket configuration

so i want to trigger a function on

event: s3:ObjectCreated:*

and a different function on

event: s3:ObjectRemoved:*

any advice is much appreciated

2

It seems like you would need to have different function definitions. Like:

functions:

````    handler: resize.handler
````    events:
````     - s3: 
````         bucket: photos
````         event: s3:ObjectCreated:*
````  otherfunc:
````    handler: resize.handler
````    events:
````     - s3: 
````         bucket: photos
````         event: s3:ObjectRemoved:*

And then continue with the bucket customization as you already have.

3

Adding event in the function does not work, you have to add it to the AWS::S3::Bucket, as:

        NotificationConfiguration:
          LambdaConfigurations:
            - Event: 's3:ObjectCreated:*'
              Function:
                "Fn::GetAtt":
                  - ProcessLambdaFunction
                  - Arn
            - Event: 's3:ObjectRemoved:*'
              Function:
                "Fn::GetAtt":
                  - ReprocessLambdaFunction
                  - Arn

here is the complete Resource, note that we also have to create the LambdaPermission for each of the functions, specifically the Naming conventions are XxxLambdaPermissionYyy where Xxx is the lambda function and Yyy is the bucket reference in the function

  process:
    handler: bin/process
    description: Process CSV files function when file has been added to S3 bucket
    package:
      individually: true
      include:
        - ./bin/process
    memorySize: 128
    timeout: 30
    events:
      - s3: csv

  reprocess:
    handler: bin/reprocess
    description: Reprocess CSV files function when files have been deleted
    package:
      individually: true
      include:
        - ./bin/reprocess
    memorySize: 128
    timeout: 30
    events:
      - s3: csv

resources:
  Resources:
    S3BucketCsv:
      Type: AWS::S3::Bucket
      Properties:
        BucketName: ${file(./config.yml):${opt:stage}.CSV_BUCKET}
        # add additional custom bucket configuration here
        NotificationConfiguration:
          LambdaConfigurations:
            - Event: 's3:ObjectCreated:*'
              Function:
                "Fn::GetAtt":
                  - ProcessLambdaFunction
                  - Arn
            - Event: 's3:ObjectRemoved:*'
              Function:
                "Fn::GetAtt":
                  - ReprocessLambdaFunction
                  - Arn
        LifecycleConfiguration:
          Rules:
            - Id: "Delayed csv expiration"
              Status: "Enabled"
              TagFilters:
                  - Key: "deleted-csv"
                    Value: "true"
              ExpirationInDays: 1

    CsvBucketPolicy:
      Type: AWS::S3::BucketPolicy
      Properties:
        Bucket: ${file(./config.yml):${opt:stage}.CSV_BUCKET}
        PolicyDocument:
          Statement:
            - Action:
                - s3:putObject
              Effect: "Allow"
              Principal:
                "AWS":
                  - "arn:aws:iam::#{AWS::AccountId}:root"
              Resource:
                - "arn:aws:s3:::${file(./config.yml):${opt:stage}.CSV_BUCKET}/*.xls"
                - "arn:aws:s3:::${file(./config.yml):${opt:stage}.CSV_BUCKET}/*.csv"
                - "arn:aws:s3:::${file(./config.yml):${opt:stage}.CSV_BUCKET}/*.tsv"
                - "arn:aws:s3:::${file(./config.yml):${opt:stage}.CSV_BUCKET}/*.xlsx"

    ProcessLambdaPermissionCsvS3:
      Type: "AWS::Lambda::Permission"
      Properties:
        FunctionName:
          "Fn::GetAtt":
            - ProcessLambdaFunction
            - Arn
        Principal: "s3.amazonaws.com"
        Action: "lambda:InvokeFunction"
        SourceAccount:
          Ref: AWS::AccountId
        SourceArn: "arn:aws:s3:::${file(./config.yml):${opt:stage}.CSV_BUCKET}"

    ReprocessLambdaPermissionCsvS3:
      Type: "AWS::Lambda::Permission"
      Properties:
        FunctionName:
          "Fn::GetAtt":
            - ReprocessLambdaFunction
            - Arn
        Principal: "s3.amazonaws.com"
        Action: "lambda:InvokeFunction"
        SourceAccount:
          Ref: AWS::AccountId
        SourceArn: "arn:aws:s3:::${file(./config.yml):${opt:stage}.CSV_BUCKET}"

Hope this helps others