loc_mods's Introduction

Library of Congress MODS in Ruby

Purpose

This is a class-oriented Ruby library that parses LOC’s MOD data.

This gem is developed using the MODS 3.7 XSD schema.

Usage

Ruby API

require 'loc_mods'

# Single record under `<modsCollection>`
LocMods::Collection.from_xml(File.read("spec/fixtures/record_1.xml"))

# Full NIST Tech Pubs records
# https://github.com/usnistgov/NIST-Tech-Pubs/tree/nist-pages/xml
LocMods::Collection.from_xml(File.read("reference/allrecords-MODS.xml"))

Command line interface

LocMods provides a command-line interface (CLI) for various operations. The main executable is loc-mods.

Detect duplicates

The detect-duplicates command allows you to find duplicate MODS records based on using a "primary ID" that is their DOI (Digital Object Identifier).

Usage:

$ loc-mods detect-duplicates [OPTIONS] <file_or_directory_path>

Options:

-r, --recursive: Search for MODS files recursively in subdirectories.
-v, --verbose: Display more detailed output.
-o, --output FILE: Write the results to a file instead of stdout.

Example:

$ loc-mods detect-duplicates -r -v /path/to/mods/files

This command will:

Search for MODS XML files in the specified directory (and subdirectories if -r is used).
Parse each MODS file and extract the DOI.
Group records with the same DOI.
For each group of duplicates:
1. Display the shared DOI.
2. List the filenames of the duplicate records.
3. Show a detailed comparison of the differences between the records.

The output will highlight differences, removed elements, and missing elements between the duplicate records, helping you identify discrepancies in the metadata.