no issue
We missed handling `undefined` values for fields during csv export for memebrs, which causes csv entries as `undefined` for fields that don't exist. It also added need for extra handling of `undefined` entries during csv import. This PR fixes the bug by properly handling empty/undefined values in export
no issue
- New fields that are accepted through members CSV import endpoint are:
- `subscribed_to_emails` - corresponds to `subscribed` flag in API
- `stripe_customer_id` - links existing Stripe customer to created member
- `complimentary_plan` - flag controlling "Complimentary" plan subscription creation for imported member
- Noteworthy exception in field naming - `subscribed_to_emails` that corresponds to `subscribed` API flag present on members resources. It's a special case of CSV format, where users can be less technical it's more explicit to what the flag does (also the same naming is applied in the Admin UI)
- Failing to either link Stripe customer or assign "Complimentary" subscription to imported member behaves in a transaction-like manner - imported record is not created in the database. This is needed to be able to retry imports when it fails for reasons like connectivity failure with Stripe or Stripe miss-configuration.
- To avoid conflicts with linking same Stripe customer to multiple members there is a special handling for duplicate `stripe_customer_id` fields. Records with duplicates are removed from imported set.
