Issue #10054 has been reported by Dmitriy Semenyuk.

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Bug #10054: Net::HTTPGenericRequest sets host even if it was set before by user
https://bugs.ruby-lang.org/issues/10054

* Author: Dmitriy Semenyuk
* Status: Open
* Priority: Normal
* Assignee: 
* Category: lib
* Target version: 
* ruby -v: ruby 2.1.2p95 (2014-05-08 revision 45877) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
~~~
# there is SSH tunnel that forwards 127.0.0.1:9293 to google.com:80
request = Net::HTTP::Post.new(URI("http://127.0.0.1:9293")).tap do |req|
  req.form_data = {q: "ruby"}
  req["Host"] = "google.com"
end
~~~

This code ignores host that was already set (it uses "#{host}:#{uri}"):

~~~
Net::HTTP.start(uri.hostname, uri.port) { |http| http.request(request) }
~~~

I encountered this bug when tried to connect to remote server using SSH tunnel (/etc/hosts isn't available to edit).

Resolution:

https://bugs.ruby-lang.org/projects/ruby-trunk/repository/entry/lib/net/http/generic_request.rb line 119

~~~
def exec(sock, ver, path)   #:nodoc: internal use only
-    if @uri
+    if @uri && !self['host']
      if @uri.port == @uri.default_port
~~~



-- 
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