Add support for PDF/A-1b

.travis.yml

@@ -1,8 +1,15 @@
 language: ruby
+env:
+  - VERAPDF_VERSION=1.6.3 VERAPDF_VERSION_SHORT=1.6
 before_install:
   - gem update --system
   - gem install bundler
   - bundle --version
+  - wget http://software.verapdf.org/rel/${VERAPDF_VERSION_SHORT}/verapdf-${VERAPDF_VERSION}-installer.zip
+  - unzip verapdf-${VERAPDF_VERSION}-installer.zip
+  - java -jar -DINSTALL_PATH=${PWD}/verapdf verapdf-${VERAPDF_VERSION}/verapdf-izpack-installer-${VERAPDF_VERSION}.jar -options-system
+  - export PATH=$PATH:$PWD/verapdf
+  - verapdf --version
 rvm:
   - 2.1.0-p0
   - 2.1.10

lib/prawn/document.rb

@@ -66,7 +66,8 @@ class Document
       :page_size, :page_layout, :margin, :left_margin,
       :right_margin, :top_margin, :bottom_margin, :skip_page_creation,
       :compress, :background, :info,
-      :text_formatter, :print_scaling
+      :text_formatter, :print_scaling,
+      :enable_pdfa_1b
     ].freeze
 
     # Any module added to this array will be included into instances of

spec/extensions/vera_pdf_helpers.rb

@@ -0,0 +1,48 @@
+require 'rexml/document'
+require 'open3'
+
+module VeraPdfHelpers
+  VERA_PDF_EXECUTABLE = 'verapdf'.freeze
+  VERA_PDF_COMMAND = "#{VERA_PDF_EXECUTABLE} --flavour 1b --format xml".freeze
+
+  def which(cmd)
+    exts = ENV['PATHEXT'] ? ENV['PATHEXT'].split(';') : ['']
+    ENV['PATH'].split(File::PATH_SEPARATOR).each do |path|
+      exts.each do |ext|
+        exe = File.join(path, "#{cmd}#{ext}")
+        return exe if File.executable?(exe) && !File.directory?(exe)
+      end
+    end
+    return nil
+  end
+
+  def vera_pdf_available?
+    which VERA_PDF_EXECUTABLE
+  end
+
+  def valid_pdfa_1b?(pdf_data)
+    stdout, stderr, status = Open3.capture3(VERA_PDF_COMMAND, stdin_data: pdf_data)
+    raise Exception, "VeraPDF could not be run. #{stderr}" unless status.success?
+
+    reported_as_compliant? stdout.lines[4..-1].join
+  end
+
+  def reported_as_compliant?(xml_data)
+    xml_doc = REXML::Document.new xml_data
+    xml_doc.elements.each('/processorResult/validationResult/ns2:assertions/ns2:assertion') do |element|
+      message = element.elements.to_a('ns2:message').first.text
+      clause = element.elements.to_a('ns2:ruleId').first.attributes['clause']
+      test = element.elements.to_a('ns2:ruleId').first.attributes['testNumber']
+      context = element.elements.to_a('ns2:location/ns2:context').first.text
+      url = 'https://github.com/veraPDF/veraPDF-validation-profiles/wiki/PDFA-Part-1-rules'
+      url_anchor = "rule-#{clause.delete('.')}-#{test}"
+      puts
+      puts 'PDF/A-1b VIOLATION'
+      puts "  Message: #{message}"
+      puts "  Context: #{context}"
+      puts "  Details: #{url}##{url_anchor}"
+      puts
+    end
+    xml_doc.elements.to_a('/processorResult/validationResult').first.attributes['isCompliant'] == 'true'
+  end
+end

spec/manual_spec.rb

@@ -5,7 +5,7 @@
 MANUAL_HASH =
   case RUBY_ENGINE
   when 'ruby'
-    'b55f154c9093c60f38051c75920c8157c775b946b0c77ffafc0a8a634ad5401e8ceafd0b96942839f82bacd726a690af3fdd1fd9e185616f67c6c0edfcfd0460'
+    '9b2fde84364fdde4d879c4a29072bab38dfb89e3397923ae7a5a430e96fe7fb3c5dd59962152f47940b854a2d0806c555010258e03e8d462ae2feace8637c653'
   when 'jruby'
     'd2eb71ea3ddc35acb185de671a6fa48862ebad5727ce372e3a742f45d31447765c4004fbe5fbfdc1f5a32903ac87182c75e6abe021ab003c8af6e6cc33e0d01e'
   end

spec/prawn/pdfa_1b_spec.rb

@@ -0,0 +1,10 @@
+require 'spec_helper'
+
+include VeraPdfHelpers
+
+if vera_pdf_available?
+  require_relative 'pdfa_1b_spec_impl'
+else
+  puts 'NOTICE: Specs for PDF/A-1b are not run, because veraPDF ' \
+       'binary was not found in path.'
+end

spec/prawn/pdfa_1b_spec_impl.rb

@@ -0,0 +1,30 @@
+require 'spec_helper'
+
+describe Prawn::Document do
+  include VeraPdfHelpers
+
+  let(:pdf) { described_class.new(enable_pdfa_1b: true) }
+
+  describe 'PDF/A 1b conformance' do
+    it 'empty document' do
+      expect(valid_pdfa_1b?(pdf.render)).to be true
+    end
+
+    it 'document with some text' do
+      pdf.font_families.update(
+        'DejaVuSans' => {
+          normal: "#{Prawn::DATADIR}/fonts/DejaVuSans.ttf"
+        }
+      )
+      pdf.font 'DejaVuSans' do
+        pdf.text_box 'Some text', at: [100, 100]
+      end
+      expect(valid_pdfa_1b?(pdf.render)).to be true
+    end
+
+    it 'document with some image' do
+      pdf.image "#{Prawn::DATADIR}/images/pigs.jpg"
+      expect(valid_pdfa_1b?(pdf.render)).to be true
+    end
+  end
+end