Module date_utils 

Date and datetime utilities.

EDTF level 0 (ISO 8601 subset used by DataCite and InvenioRDM) is the primary parser. A manual fallback handles malformed dates from upstream sources (e.g. single-digit months like “2023-8-25”).

Mirrors the Go dateutils package in front-matter/commonmeta.

Functions

date_from_parts

Build an ISO 8601 partial date from numeric parts. Pass 0 for month or day to omit that component. date_from_parts(2023, 8, 5) → "2023-08-05".

date_from_str_parts

Build an ISO 8601 partial date from string parts (empty string = omit). Used for Crossref XML and RIS date fields.

date_only

Return only the date portion of a datetime string (first 10 characters). "2024-01-15T12:34:56Z" → "2024-01-15". Pass-through for shorter strings.

normalize_date

Pad single-digit month/day components to two digits so they are valid EDTF/ISO 8601. "2023-8-5" → "2023-08-05", "2023-8-5T12:00:00" → "2023-08-05T12:00:00".

parse_date

Parse a date or datetime string and return an ISO 8601 date ("YYYY", "YYYY-MM", or "YYYY-MM-DD"). Time components are discarded.

parse_datetime

Parse a date or datetime string and return an ISO 8601 datetime ("YYYY-MM-DDTHH:MM:SSZ"), or a date-only string when the time is midnight. Returns "" on failure.

sanitize_date

Sanitize an arbitrary date string from upstream sources into valid EDTF / ISO 8601. Handles, in order:

strip_milliseconds

Remove sub-second fractions from an ISO 8601 datetime string. A midnight time component (T00:00:00) is stripped entirely, leaving only the date. Normalises +00:00 timezone suffix to Z.

unix_to_date

Convert a Unix timestamp to an ISO 8601 date string ("YYYY-MM-DD").

unix_to_datetime

Convert a Unix timestamp to an ISO 8601 datetime string ("YYYY-MM-DDTHH:MM:SSZ").