th: smile sweet sadistic surprise service

should've just hardcoded instead but noooooooooooo

"needs to be decent"

app/lib/request.rb

@@ -261,9 +261,28 @@ class Request
         begin
           addresses = [IPAddr.new(host)]
         rescue IPAddr::InvalidAddressError
-          Resolv::DNS.open do |dns|
-            dns.timeouts = 5
-            addresses = dns.getaddresses(host)
+          begin
+            Resolv::DNS.open do |dns|
+              dns.timeouts = 5
+              addresses = dns.getaddresses(host)
+              addresses = addresses.filter { |addr| addr.is_a?(Resolv::IPv6) }.take(2) + addresses.filter { |addr| !addr.is_a?(Resolv::IPv6) }.take(2)
+            end
+          rescue ResolvError
+          end
+
+          if addresses.empty?
+            # try /etc/hosts file
+            # https://github.com/mastodon/mastodon/issues/9436
+            Resolv::Hosts.new.each_address(host) do |address|
+              case address
+              when Resolv::IPv4::Regex
+                addresses << Resolv::IPv4.create(address)
+              when Resolv::IPv6::Regex
+                addresses << Resolv::IPv6.create(address)
+              else
+                raise ResolvError.new("cannot interpret as address: #{address}")
+              end
+            end
             addresses = addresses.filter { |addr| addr.is_a?(Resolv::IPv6) }.take(2) + addresses.filter { |addr| !addr.is_a?(Resolv::IPv6) }.take(2)
           end
         end