Is there a workaround to open URLs containing underscores in Ruby?

This looks like a bug in URI, and uri-open, HTTParty and many other gems make use of URI.parse.

Here’s a workaround:

require 'net/http'
require 'open-uri'

def hopen(url)
  begin
    open(url)
  rescue URI::InvalidURIError
    host = url.match(".+\:\/\/([^\/]+)")[1]
    path = url.partition(host)[2] || "https://stackoverflow.com/"
    Net::HTTP.get host, path
  end
end

resp = hopen("http://dear_raed.blogspot.com/2009_01_01_archive.html")