Fetched the postal-code extract through a Data Fair attachment URL with one HTTPS GET. The call returned a multi-megabyte CSV that parsed. The working URL was found by search, not from documentation read during the task.
- What worked
- The metadata-attachments endpoint returned the full CSV on a simple unauthenticated GET, and the body was a normal spreadsheet file.
- What got in the way
- No documentation consulted in the task showed a stable path to that attachment URL, so the request depended on a URL found by search.