How do I safely join relative url segments?

Question

I\'m trying to find a robust method of joining partial url path segments together. Is there a quick way to do this?

I tried the following:

puts URI::         


        

Answer 1

You can use this:

URI.join('http://exemple.com', '/a/', 'b/', 'c/', 'd')
=> #<URI::HTTP http://exemple.com/a/b/c/d>
URI.join('http://exemple.com', '/a/', 'b/', 'c/', 'd').to_s
=> "http://exemple.com/a/b/c/d"

See: http://ruby-doc.org/stdlib-2.4.1/libdoc/uri/rdoc/URI.html#method-c-join-label-Synopsis

Answer 2

Have uri as URI::Generic or subclass of thereof

uri.path += '/123' 

Enjoy!

06/25/2016 UPDATE for skeptical folk

require 'uri'
uri = URI('http://ioffe.net/boris')
uri.path += '/123'
p uri

Outputs

 <URI::HTTP:0x2341a58 URL:http://ioffe.net/boris/123>

Run me

Answer 3

You can use File.join('resource/', '/edit', '12?option=test')

Answer 4

My understanding of URI::join is that it thinks like a web browser does.

To evaluate it, point your mental web browser to the first parameter, and keep clicking links until you browse to the last parameter.

For example, URI::join('http://example.com/resource/', '/edit', '12?option=test'), you would browse like this:

• http://example.com/resource/, click a link to /edit (a file at the root of the site)
• http://example.com/edit, click a link to 12?option=test (a file in the same directory as edit)
• http://example.com/12?option=test

If the first link were /edit/ (with a trailing slash), or /edit/foo, then the next link would be relative to /edit/ rather than /.

This page possibly explains it better than I can: Why is URI.join so counterintuitive?

Answer 5

I improved @Maximo Mussini's script to make it works gracefully:

SmartURI.join('http://example.com/subpath', 'hello', query: { token: secret })
=> "http://example.com/subpath/hello?token=secret"

https://gist.github.com/zernel/0f10c71f5a9e044653c1a65c6c5ad697

require 'uri'

module SmartURI
  SEPARATOR = '/'

  def self.join(*paths, query: nil)
    paths = paths.compact.reject(&:empty?)
    last = paths.length - 1
    url = paths.each_with_index.map { |path, index|
      _expand(path, index, last)
    }.join
    if query.nil?
      return url
    elsif query.is_a? Hash
      return url + "?#{URI.encode_www_form(query.to_a)}"
    else
      raise "Unexpected input type for query: #{query}, it should be a hash."
    end
  end

  def self._expand(path, current, last)
    if path.starts_with?(SEPARATOR) && current != 0
      path = path[1..-1]
    end

    unless path.ends_with?(SEPARATOR) || current == last
      path = [path, SEPARATOR]
    end

    path
  end
end