[Feature Request]: YAML - how to output the error of error_handling in sub yaml?

[ZwxwZ]

What would you like to happen?

For example,
mainl.yaml

pipeline:
  transforms:
    - type: ReadFromCsv
      config:
        path: /path/to/input*.csv

    - type: MapToFields
      name: ComputeRatio
      input: ReadFromCsv
      config:
        language: python
        fields:
          col1: col1
        error_handling:
          output: my_error

......

    - type: **RaiseElementToPower**
      name: RaiseElementToPowerName
      input: XXX

    - type: LogError
      name: LogForTesting
      input: 
         - ComputeRatio.my_error_output
         - RaiseElementToPowerName.my_error
providers:
  - include: "file://sub.yaml"

sub.yaml

- type: yaml
  transforms:
    # Define the first transform of type "RaiseElementToPower"
    RaiseElementToPower:
      config_schema:
        properties:
          n: {type: integer}
      body:
        type: chain
        transforms:
          - type: MapToFields
            config:
              language: python
              append: true
              fields:
                power: "element ** {{n}}"
              error_handling:
                output: my_error

Now it will have error, and the error info said that we didn't output the error,

      input: 
         - ComputeRatio.my_error_output
         - RaiseElementToPowerName.my_error

so, i want to know,
how to output the error when the error is in the yaml provider

Issue Priority

Priority: 2 (default / most feature requests should be filed as P2)

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[derrickaw]

Hi @ZwxwZ,

1. Opened a PR to give more examples of usage - [yaml] : add more error handling tests and website example #37245.
2. In your particular case, I think one area of your code needs two slight tweaks and it should work:
   • type: LogError <-- Change this to LogForTesting
     name: LogForTesting <-- keep or change to whatever
     input:
     • ComputeRatio.my_error_output <-- Change this to ComputeRatio.my_error
     • RaiseElementToPowerName.my_error