Module: Glossarist::Rdf::DeterministicSlug

Defined in:

lib/glossarist/rdf/deterministic_slug.rb

Overview

Deterministic slug helper for RDF subject URIs.

When an entity has no natural-language identifier (no source/id pair, no text), derive a deterministic short slug from its content fingerprint. Same content → same slug across runs and across processes; different content → different slug (modulo collision probability).

Hash choice:

- SHA-256 (not MD5). MD5 is deprecated for new code; SHA-256
is the modern baseline and is free performance-wise.
- Truncated to 16 hex chars (64 bits). Birthday-paradox
collision probability at 4 million items < 1e-9, comfortable
margin for any realistic dataset.

Previous width was 12 chars (48 bits) using MD5 — collision probability at 100k items was ~0.3%, too high for RDF merge.

Constant Summary

HASH_WIDTH =

16

Class Method Summary

• .from_parts(*parts) ⇒ Object

Class Method Details

.from_parts(*parts) ⇒ Object

# File 'lib/glossarist/rdf/deterministic_slug.rb', line 27

def self.from_parts(*parts)
  joined = parts.compact.join("|")
  Digest::SHA256.hexdigest(joined)[0, HASH_WIDTH]
end