I have multiple books and have CSV files per book containing the chapters and their content. The CSV columns are called "Chapter Number" and "Text". On the Drupal website I have created a node for each book. I want to import the chapters so the chapters also get an entity reference to the right book when they are saved. Creating an importer for each book is not an option since there will be more added frequently.
For each imported node an entity reference field is required. This data does not exist in the uploaded CSV data, but should be provied by the Drupal website.
Essentially I want a View listing all my books with an import button next to each row.
I was able to pass this data as a GET value in the URL, but unfortunately this value is lost when the batch starts after clicking the submit button.
I hope someone can point me to the right direction! I've been searching the web for many hours and was not able to find anything related to this issue.