EpiDoc Validator

JRuby library for validating EpiDoc XML.

Installation

Add this line to your application's Gemfile:

gem 'epi_doc_validator'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install epi_doc_validator

(See project at rubygems.org)

Requirements

• JRuby >= 9.2.9

Usage

require 'epi_doc_validator'

validator = EpiDocValidator::Validator.new
xml = File.read('my-epi-doc-file.xml')

# Validate against latest schema
validator.valid?(xml) # => `true` or `false`

# Validate against a specific schema version
validator.valid?(xml, version: '9.1') # => `true` or `false`
                                      # => raises exception if version doesn't exist

# Get list of versions
validator.versions # => `["8", "8-rc1", "8.2", ... , "dev", "latest"]`

# Validate and return a list of errors
validator.errors(xml) # => array of errors (`[]` if valid)

# Validate and return a list of errors for a specific schema version
validator.errors(xml, version: '9.1') # => array of errors (`[]` if valid)
                                      # => raises exception if version doesn't exist

Development

Setup

• bundle install

Running tests

• bundle exec rspec

Linting the code

• bundle exec rubocop

Auditing the code

• bundle exec bundler-audit check --update

Updating schemas

• bash scripts/update-schema.sh (requires wget)

Publishing

• Bump version in lib/epi_doc_validator/version.rb
• Commit and push to GitHub
• On GitHub, create a new release
• Run gem build epi_doc_validator.gemspec
• Run gem push epi_doc_validator-X.Y.Z-java.gem

Notes

Currently, the library only works with JRuby. All of the code in this repository works with both Ruby MRI and JRuby. In the future we hope to release a version that works with Ruby MRI.

The problem is that the EpiDoc schema is written in something called RELAX NG. Nokogiri, the main XML processing library for Ruby, uses libxml2 with Ruby MRI and jing with JRuby. jing works correctly, but there are at least two long-standing bugs in libxml2's RELAX NG validation code. Until these are fixed, this library is too unstable with Ruby MRI to release.

List of (known) bugs:

• 2008: "RNG internal error trying to compile notAllowed" warning is printed multiple times (link)
• 2012: Validation never terminates on occasion (link)

For a more detailed explanation of this problem in a slightly different domain, see Hugh Cayless's post Experiment: is the JavaScript port of libxml2 viable?:

Result: Inconclusive; lean towards endless screaming.