I have a S3 resource definition where the object path(regexp) need to have a date variable in it.

resources:
  - name: add_file_to_s3
    type: s3
    source:
      access_key_id: ((access_key_id))
      bucket: pipeline-assets
      regexp: size_monitor/((date))/size_(.*).csv
      secret_access_key: ((secret_access_key))

I have tried creating a task generate-date for generating the current date, loading it and passing it to add_file_to_s3 resource.

jobs:
  - name: size-monitor  
    serial: true
    plan:
      - in_parallel:
        - get: ci-image
        - get: repo
          trigger: true
          passed:
          - set-pipeline
      - task: generate-date
        image: ci-image
        config:
          platform: linux
          outputs:
            - name: current-date        
          run:
            path: /bin/sh
            args:
            - -c
            - |
              DATE=$(date +%Y-%m-%d)
              echo $DATE > current-date/date.env
      - load_var: current_date
        file: current-date/date.env
      - task: size-monitor-script
        image: ci-image
        file: repo/ci/size_monitor/task.yml
        params:
        #params here
      - put: add_file_to_s3
        params:
          file: output_dir/size_*.csv
          date: current_date

The task size-monitor-script will generate a csv file at the location output_dir/size_*.csv.

This logic is not passing the date variable to the resource. Is there any other way it could be passed? Any help would be greatly appreciated. Thanks!