url_validation

shrivel.ex

defmodule Shrivel do
  def valid?(url) do
    regex = "^(?:(?:https?|ftp):\/\/)"
      <> "(?:\S+(?::\S*)?@)?"
      <> "(?:"
      <> "(?!(?:10|127)(?:\.\d{1,3}){3})"
      <> "(?!(?:169\.254|192\.168)(?:\.\d{1,3}){2})"
      <> "(?!172\.(?:1[6-9]|2\d|3[0-1])(?:\.\d{1,3}){2})"
      <> "(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])"
      <> "(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}"
      <> "(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))"
      <> "|(?:(?:[a-z\x{00a1}-\x{ffff}0-9]-*)*[a-z\x{00a1}-\x{ffff}0-9]+)"
      <> "(?:\.(?:[a-z\x{00a1}-\x{ffff}0-9]-*)*[a-z\x{00a1}-\x{ffff}0-9]+)*"
      <> "(?:\.(?:[a-z\x{00a1}-\x{ffff}]{2,}))\.?)(?::\d{2,5})?(?:[\/?#]\S*)?$"
    Regex.match?(~r/#{regex}/uim, url)
  end
end

shrivel_test.exs

defmodule ShrivelTest do
  use ExUnit.Case
  doctest Shrivel

  test "url is valid" do
    urls = [
      "http://foo.com/blah_blah",
      "http://foo.com/blah_blah/",
      "http://foo.com/blah_blah_(wikipedia)",
      "http://foo.com/blah_blah_(wikipedia)_(again)",
      "http://www.example.com/wpstyle/?p=364",
      "https://www.example.com/foo/?bar=baz&inga=42&quux",
      "http://✪df.ws/123",
      "http://userid:password@example.com:8080",
      "http://userid:password@example.com:8080/",
      "http://userid@example.com",
      "http://userid@example.com/",
      "http://userid@example.com:8080",
      "http://userid@example.com:8080/",
      "http://userid:password@example.com",
      "http://userid:password@example.com/",
      "http://142.42.1.1/",
      "http://142.42.1.1:8080/",
      "http://➡.ws/䨹",
      "http://⌘.ws",
      "http://⌘.ws/",
      "http://foo.com/blah_(wikipedia)#cite-1",
      "http://foo.com/blah_(wikipedia)_blah#cite-1",
      "http://foo.com/unicode_(✪)_in_parens",
      "http://foo.com/(something)?after=parens",
      "http://☺.damowmow.com/",
      "http://code.google.com/events/#&product=browser",
      "http://j.mp",
      "ftp://foo.bar/baz",
      "http://foo.bar/?q=Test%20URL-encoded%20stuff",
      "http://مثال.إختبار",
      "http://例子.测试",
      "http://उदाहरण.परीक्षा",
      "http://-.~_!$&'()*+,;=:%40:80%2f::::::@example.com",
      "http://1337.net",
      "http://a.b-c.de",
      "http://223.255.255.254",
      "jnekavmekra"
    ]

    Enum.all? urls, &(Shrivel.valid?(&1))
  end
end