Hi Everyone. I am trying to run

meltano install

but it fails with the following message

Failed to parse JSON array from string: 'None'

Python 3.10.10

meltano, version 3.1.0

$ meltano install
Installing 9 plugins...
Skipped installing mapper 'transform-field-custom'...
Installing extractor 'tap-mysql'...
Installing extractor 'tap-singer-jsonl'...
Installing loader 'target-jsonl'...
Installing loader 'target-parquet'...
Installing loader 'target-s3'...
Installing loader 'target-s3-parquet'...
Installing loader 'target-singer-jsonl'...
Installing mapper 'transform-field-custom'...
Need help fixing this problem? Visit <http://melta.no/> for troubleshooting steps, or to
join our friendly Slack community.

Failed to parse JSON array from string: 'None'

I've run again with

meltano --log-level=debug

and the issue seems to be with installing my custom

transform-field

mapper

Installing mapper 'transform-field-custom'...
2023-11-01T17:16:46.144149Z [debug    ] Packages for 'mappers/transform-field-custom' have changed so performing a clean install.
2023-11-01T17:16:46.146434Z [debug    ] Removed old virtual environment for 'mappers/transform-field-custom'
2023-11-01T17:16:46.146584Z [debug    ] Creating virtual environment for 'mappers/transform-field-custom'
2023-11-01T17:16:46.167154Z [debug    ] Need help fixing this problem? Visit <http://melta.no/> for troubleshooting steps, or to
join our friendly Slack community.

Mapper is defined as follows in my

meltano.yml

file

mappers:
  - name: transform-field-custom
    namespace: transform_field_custom
    pip_url: git+<https://github.com/><my-github-id>/pipelinewise-transform-field.git
    executable: transform-field
    mappings:
      ... ...