docs/schema.md

_source.json Sidecar Schema

Every downloaded file (or group of files from the same source) in CatholicCorpus has a companion _source.json sidecar that documents where it came from, who made it available, and how it may be used. This is the formal schema for those sidecars.

The machine-readable JSON Schema (draft 2020-12) is at schema.json.

Fields

Top-level

Field	Type	Required	Description
corpus	string	Yes	Always "CatholicCorpus.org". Identifies this file as part of the project.
source_name	string	Yes	Human-readable name of the source.
source_url	string (URI)	Yes	URL from which the content was downloaded.
upstream_url	string (URI)	Yes	Canonical URL of the original project. May equal source_url.
description	string	Yes	What this source contains and why it matters.
language	string	Yes	Primary language(s). See controlled values below.
date_downloaded	string (date)	Yes	ISO 8601 date of download (YYYY-MM-DD).
license	string	Yes	Short license identifier. See controlled values below.
license_url	string or null	Yes	URL to full license text. Null for public domain.
license_details	string	Yes	Extended explanation of the licensing situation.
attribution_required	boolean	Yes	Whether attribution must be given when using this content.
attribution_text	string or null	Yes	Copy-paste-ready attribution text. Null if not required.
credit	object	Yes	Structured credit information (see below).
format	string	Yes	File format(s) of the content.
estimated_words	string or number	Yes	Approximate word count.
notes	string or null	Yes	Additional context, or null.
article_count	string	No	Number of discrete articles (encyclopedia-type sources only).

The credit object

Field	Type	Required	Description
digitized_by	string	Yes	Institution or person who created the digital version.
digitizer_url	string (URI)	Yes	URL of the digitization project.
original_author	string	Yes	Original author(s) of the text.
translator	string or null	No	Translator, if applicable. Null for original-language texts.
editor	string or null	No	Editor of the edition used.
publisher	string or null	No	Historical print publisher.
publication_year	string or null	No	Year or range of the print edition.
thank_you	string	Yes	Human-readable acknowledgment.

Controlled Vocabularies

license values

Value	Meaning
Public Domain	Work is in the public domain (pre-1928 U.S. publication or author deceased 70+ years). No restrictions on use.
CC BY 4.0	Creative Commons Attribution 4.0. Free to use with attribution.
CC BY-NC-SA 4.0	Creative Commons Attribution-NonCommercial-ShareAlike 4.0.
CC BY 4.0 with additional EULA	CC BY 4.0 with an additional end-user license for specific uses (e.g., SBLGNT commercial use restriction).
Non-commercial use permitted	May be used for non-commercial purposes. Check license_details for specifics.
Copyrighted (not redistributable)	Content is under copyright. Scripts to download it are included but the content itself is not in the corpus.
Unclear	License status could not be determined. Check license_details for what is known.

language values

The language field uses standard language names, not ISO codes. Common values in the corpus:

• Latin
• Ancient Greek
• English
• Latin (primary), English (translations)
• Latin, Greek
• Multilingual

For multilingual sources, the primary language is listed first.

How Edition and Citation References Work

Patrologia Latina references

For texts from the Migne Patrologia Latina (Task 02), the standard scholarly citation format is PL volume:column (e.g., PL 32:659 for Augustine's Confessions, Book 1, Chapter 1). The Corpus Corporum download preserves the internal structure of each text but does not embed column numbers in the TEI XML. Researchers needing precise PL column references should cross-reference with the original Migne volumes (available in Task 16 for the Graeca, or via the PDF volumes on archive.org for the Latina).

Archive.org item IDs

For texts downloaded from archive.org, the source_url contains the archive.org identifier (e.g., https://archive.org/details/summatheologica01thom). This identifier can be used to access the original metadata, alternative formats, and lending status via the archive.org API.

Three-Tier License Model

The corpus uses a three-tier approach:

1. Tier 1 (Public Domain): The vast majority. No restrictions. Use freely.
2. Tier 2 (Creative Commons): A small number of texts. Follow the CC license terms (attribute, and for NC licenses, do not use commercially).
3. Tier 3 (Copyrighted): Task 17 only. Scripts are MIT-licensed; content is not redistributed. Users who run the scripts are responsible for their own compliance.

The license field in each sidecar tells you which tier a given source belongs to.

Validation

To validate your sidecars against this schema:

pip install jsonschema
python3 -c "
import json, jsonschema, glob
schema = json.load(open('docs/schema.json'))
files = glob.glob('**/_source.json', recursive=True)
errors = 0
for f in files:
    try:
        jsonschema.validate(json.load(open(f)), schema)
    except jsonschema.ValidationError as e:
        print(f'{f}: {e.message}')
        errors += 1
print(f'Validated {len(files)} files, {errors} errors')
"