Ruby using namespace/module

Question

For example:

require 'net/http'
uri = URI('http://example.com/some_path?query=string')

Net::HTTP.start(uri.host, uri.port) do |http|
  request = Net::HTTP::Get.new uri

  response = http.request request # Net::HTTPResponse object
end

What is the correct/rubist way to get rid of Net::HTTP ? i.e. HTTP::Get.new() or just Get.new()

@sawa don't remove the tag `net-http`.It is needed for future search on `SO`. — Arup Rakshit, Jun 25 '13 at 15:07

tadman · Accepted Answer · 2013-06-25T17:51:43.500

19

If you want to shorten these, you can just import that namespace:

Net::HTTP.start(...)

include Net
# HTTP.start(...)

Be careful when you import aggressively as it might cause conflict within your class if you get carried away.

An alternative is to create aliases:

HTTP = Net::HTTP
Get = Net::HTTP::Get

The "correct" way is to just spell it out and not get too flustered by that. A typical Ruby program will bury this sort of low-level behavior beneath an abstraction layer so it's rarely a big deal.

edited Jun 25 '13 at 17:51

answered Jun 25 '13 at 14:29

tadman

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I can't `include Net::HTTP`, it throws error: `TypeError: wrong argument type Class (expected Module)` – w00d Jun 25 '13 at 14:44
2

Ah, I should remove that then. `include` only works on modules, but it's hard to tell how these things are structured by just looking at use cases. Aliases might work better. In any case, typing `Net::HTTP` is something that makes it abundantly clear what you're doing, and hiding that is usually a bad idea. – tadman Jun 25 '13 at 17:51

score 6 · Answer 2 · answered Jun 25 '13 at 17:24

I hope this example will clarify things.

module Foo
  def foo
    "foo"
  end
end

class Bar
  include Foo

  def bar
    "bar"
  end
end

Bar.new.foo # foo
Bar.new.bar # bar

class Baz
  extend Foo

  self.def baz
    "baz"
  end
end

Baz.foo # foo
Baz.baz # baz

Make sure you know what you are doing when you use import or extend. You could end up overriding a method that you might not want to override.

Paul · Answer 3 · 2014-11-23T22:14:48.423

2

require 'net/http'
uri = URI('http://example.com/some_path?query=string')

httpns = Net::HTTP

def get(uri)
   httpns::Get.new uri
end

http.start(uri.host, uri.port) do |http|
  request = get uri

  response = http.request request # Net::HTTPResponse object
end

in your class.

edited Nov 23 '14 at 22:14

answered Nov 23 '14 at 21:01

Paul

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Ruby using namespace/module

3 Answers3