require "open3" require "nokogiri" require "net/http" require "json" def render_cached(cache, display, string, render_comment = nil) cache.fetch(string) do |new| puts " Rendering #{render_comment || new}" res = Net::HTTP.post URI("http://localhost:8000/render"), { :equations => [ { :str => string, :display => display } ] }.to_json, "Content-Type" => "application/json" cache[string] = JSON.parse(res.body)[0] end end def perform_katex_sub(inline_cache, display_cache, content) rendered = content.gsub /\\\(((?:[^\\]|\\[^\)])*)\\\)/ do |match| render_cached(inline_cache, false, $~[1]) end rendered = rendered.gsub /\$\$((?:[^\$]|$[^\$])*)\$\$/ do |match| render_cached(display_cache, true, $~[1], "display") end return rendered end files = ARGV[0..-1] inline_cache, display_cache = {}, {} files.each do |file| puts "Rendering file: #{file}" document = Nokogiri::HTML.parse(File.open(file)) document.search('//*[not(ancestor-or-self::code)]/text()').each do |t| t.replace(perform_katex_sub(inline_cache, display_cache, t.content)) end File.write(file, document.to_html(encoding: 'UTF-8')) end