Shoes Rb Hostname not known: sub.localhost:3000

Question

I am using the shoes's GUI builder and I get the below error when I make a simple HTTP request to my local Rails server

So when I make the request

res = Net::HTTP.get(URI.parse("http://sub.localhost:3000"))

I get the error:

Hostname not known: sub.localhost
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/resolv-replace.rb:12:in `rescue in getaddress'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/resolv-replace.rb:9:in `getaddress'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/resolv-replace.rb:23:in `initialize'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:879:in `open'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:879:in `block in connect'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/timeout.rb:73:in `timeout'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:878:in `connect'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:863:in `do_start'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:852:in `start'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:1375:in `request'
shoes.rb:24:in `request'
shoes.rb:63:in `block (3 levels) in <main>'
-e:1:in `call'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/resolv-replace.rb:12:in `rescue in getaddress'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/resolv-replace.rb:9:in `getaddress'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/resolv-replace.rb:23:in `initialize'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:879:in `open'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:879:in `block in connect'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/timeout.rb:73:in `timeout'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:878:in `connect'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:863:in `do_start'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:852:in `start'
/Applications/Shoes.app/Contents/MacOS/lib/ruby/2.2.0/net/http.rb:1375:in `request'
shoes.rb:24:in `request'
shoes.rb:63:in `block (3 levels) in <main>'
-e:1:in `call'

My hosts file has 127.0.0.1 sub.localhost and I can reach the address and make requests against it no problem, just not in the shoes project.

I followed this question's advice and bound my local ip address ex 123.12.12.1, but get the same error Hostname not known: sub.123.12.12.1

This said to remove the line resolv-replace.rb:9:in in the shoes project, but I get the same error Hostname not known: sub.123.12.12.1

I'm on a Mac

Answer 1

Use a custom DNS resolver to ensure that Ruby looks at the hosts file:

require 'resolv-replace'

hosts_resolver = Resolv::Hosts.new('custom_hosts')
dns_resolver = Resolv::DNS.new

Resolv::DefaultResolver.replace_resolvers([hosts_resolver, dns_resolver])

require "net/http"
require "uri"

res = Net::HTTP.get(URI.parse("http://sub.localhost:3000"))

Now Net::HTTP will use your custom resolver that checks hosts first and successfully resolve your custom domains.