Include Processor Extension Example

Purpose: Include a file from a URI.

Asciidoctor supports including content from a URI out of the box if you set the allow-uri-read attribute (not available if the safe mode is secure).

sample-with-uri-include.adoc

:source-highlighter: coderay

.Gemfile
[source,ruby]
----
include::https://raw.githubusercontent.com/asciidoctor/asciidoctor/master/Gemfile[]
----

UriIncludeProcessor

require 'asciidoctor'
require 'asciidoctor/extensions'
require 'open-uri'

class UriIncludeProcessor < Asciidoctor::Extensions::IncludeProcessor
  def handles? target
    (target.start_with? 'http://') or (target.start_with? 'https://')
  end

  def process doc, reader, target, attributes
    content = (open target).readlines
    reader.push_include content, target, target, 1, attributes
    reader
  end
end

Usage

Asciidoctor::Extensions.register do
  include_processor UriIncludeProcessor
end

Asciidoctor.convert_file 'sample-with-uri-include.adoc', safe: :safe