rss_parser.exs

require Record

defrecord :xmlElement, Record.extract(:xmlElement, from_lib: "xmerl/include/xmerl.hrl")
defrecord :xmlText, Record.extract(:xmlText, from_lib: "xmerl/include/xmerl.hrl")
defrecord :xmlAttribute, Record.extract(:xmlAttribute, from_lib: "xmerl/include/xmerl.hrl")

defmodule RssParserTest do
  use ExUnit.Case

  def sample_xml do
    """
    <rss>
      <channel>
        <title>Example Title</title>
        <description>Custom Description</description>
        <pubDate>Wed, 11 Jun 2014 18:00:41 +0200</pubDate>
        <generator>PHP RSSGen 1.0.0 - Seld.be</generator>
        <docs>http://www.rssboard.org/rss-2-0-10</docs>
        <ttl>60</ttl>
        <language>en</language>
        <lastBuildDate>Tue, 27 May 2014 15:07:03 +0200</lastBuildDate>
        <category>PHP</category>
        <item>
          <title>Item 1</title>
          <description>Test 1</description>
          <link>http://feeds.seld.be/~r/php-blog-seld/~3/JIWnIXuFQBU/upcoming-conferences-2013</link>
          <pubDate>Tue, 19 Nov 2013 17:36:52 +0100</pubDate>
          <guid isPermaLink="false">http://seld.be/notes/upcoming-conferences-2013</guid>
          <category>News1</category>
          <category>PHP2</category>
        </item>
        <item>
          <title>Item 2</title>
          <description>Test 2</description>
          <link>http://feeds.seld.be/~r/php-blog-seld/~3/JIWnIXuFQBU/upcoming-conferences-2013</link>
          <pubDate>Tue, 19 Nov 2013 17:36:52 +0100</pubDate>
          <guid isPermaLink="false">http://seld.be/notes/upcoming-conferences-2013</guid>
          <category>News</category>
          <category>PHP</category>
        </item>
      </channel>
    </rss>
    """
  end

  test "parsing the title out of the feed" do
    {xml, _rest} = :xmerl_scan.string(bitstring_to_list(sample_xml))
    [title_element] = :xmerl_xpath.string('/rss/channel/title', xml)
    [title_text] = title_element.content
    title = title_text.value

    assert title == 'Example Title'
  end

  test "parsing the description out of the feed" do
    {xml, _rest} = :xmerl_scan.string(bitstring_to_list(sample_xml))
    [description_element] = :xmerl_xpath.string('/rss/channel/description',xml)
    [description_text] = description_element.content
    description = description_text.value

    assert description == 'Custom Description'
  end

  test "parsing the title out of the items in the feed (alternate)" do
    {xml, _rest} = :xmerl_scan.string(bitstring_to_list(sample_xml))
    items = :xmerl_xpath.string('/rss/channel/item', xml)
    item_titles = items |> Enum.map(fn(x) ->
      [title_element] = :xmerl_xpath.string('/item/title', x)
      [title_text] = title_element.content
      title_text.value
    end)

    assert item_titles == ['Item 1', 'Item 2']
  end

  test "parsing the title out of the items in the feed" do
    {xml, _rest} = :xmerl_scan.string(bitstring_to_list(sample_xml))
    items = :xmerl_xpath.string('/rss/channel/item/title/text()', xml)
    item_titles = items |> Enum.map(fn(x) -> x.value end)

    assert item_titles == ['Item 1', 'Item 2']
  end

  test "parsing the description out of the items in the feed" do
    {xml, _rest} = :xmerl_scan.string(bitstring_to_list(sample_xml))
    items = :xmerl_xpath.string('/rss/channel/item/description/text()', xml)
    item_descriptions = items |> Enum.map(fn(x) -> x.value end)

    assert item_descriptions = ['Test 1', 'Test 2']
  end

  test "parsing the categories out of the items in the feed" do
    {xml, _rest} = :xmerl_scan.string(bitstring_to_list(sample_xml))
    items = :xmerl_xpath.string('/rss/channel/item/category/text()', xml)
    item_categories = items |> Enum.map(fn(x) -> x.value end)
    assert item_categories = ['1', 'Test 2']
  end
end