transform-authors

#!/usr/bin/env python3
"""
Abbreviates a full list of authors to be '<first author> et al.' of the NDJSON
record from stdin and outputs modified records to stdout.

Note: This is a "best effort" approach and can potentially mangle the author name.
"""
import argparse
import json
import re
from sys import stderr, stdin, stdout


def parse_authors(record: dict, authors_field: str, default_value: str,
    index: int, abbr_authors_field: str = None) -> dict:
    # Strip and normalize whitespace
    new_authors = re.sub(r'\s+', ' ', record[authors_field])

    if new_authors == "":
        new_authors = default_value
    else:
        # Split authors list on comma/semicolon
        # OR "and"/"&" with at least one space before and after
        new_authors = re.split(r'(?:\s*[,，;；]\s*|\s+(?:and|&)\s+)', new_authors)[0]

        # if it does not already end with " et al.", add it
        if not new_authors.strip('. ').endswith(" et al"):
            new_authors += ' et al'

    if abbr_authors_field:
        if record.get(abbr_authors_field):
            print(
                f"WARNING: the {abbr_authors_field!r} field already exists",
                f"in record {index} and will be overwritten!",
                file=stderr
            )

        record[abbr_authors_field] = new_authors
    else:
        record[authors_field] = new_authors

    return record


if __name__ == '__main__':
    parser = argparse.ArgumentParser(
        description=__doc__,
        formatter_class=argparse.ArgumentDefaultsHelpFormatter
    )
    parser.add_argument("--authors-field", default="authors",
        help="The field containing list of authors.")
    parser.add_argument("--default-value", default="?",
        help="Default value to use if authors list is empty.")
    parser.add_argument("--abbr-authors-field",
        help="The field for the generated abbreviated authors. " +
             "If not provided, the original authors field will be modified.")

    args = parser.parse_args()

    for index, record in enumerate(stdin):
        record = json.loads(record)

        parse_authors(record, args.authors_field, args.default_value, index, args.abbr_authors_field)

        json.dump(record, stdout, allow_nan=False, indent=None, separators=',:')
        print()