Add Feed last_updated

lib/feed.ex

@@ -3,11 +3,12 @@ defmodule FeedParser.Feed do
   A feed. Contains some information about the site it originates from and a list of items it contains.
   """
 
-  defstruct [:site_url, :title, :image_url, :items]
+  defstruct [:site_url, :title, :image_url, :last_updated, :items]
 
   @type t() :: %__MODULE__{
           site_url: String.t(),
           title: String.t(),
+          last_updated: DateTime.t() | nil,
           image_url: String.t() | nil,
           items: [FeedParser.Item.t()]
         }

lib/parser/atom.ex

@@ -34,6 +34,14 @@ defmodule FeedParser.Parser.Atom do
     link = attr('/feed/link/@href', feed)
     icon = text('/feed/icon/text()', feed)
 
+    updated =
+      text('/feed/updated/text()', feed)
+      |> Timex.parse("{ISO:Extended}")
+      |> case do
+        {:ok, date} -> date
+        _ -> nil
+      end
+
     items =
       :xmerl_xpath.string('/feed/entry', feed)
       |> Enum.map(fn entry ->
@@ -65,6 +73,7 @@ defmodule FeedParser.Parser.Atom do
        site_url: link,
        title: title,
        image_url: icon,
+       last_updated: updated,
        items: items
      }}
   end

lib/parser/jsonfeed.ex

@@ -59,6 +59,7 @@ defmodule FeedParser.Parser.JSONFeed do
        site_url: home_page_url,
        title: title,
        image_url: icon,
+       last_updated: nil,
        items: items
      }}
   end

lib/parser/rss2.ex

@@ -35,6 +35,14 @@ defmodule FeedParser.Parser.RSS2 do
     link = text('/channel/link/text()', channel)
     image = text('/channel/image/url/text()', channel)
 
+    last_updated =
+      text('/channel/lastBuildDate/text()', channel)
+      |> Timex.parse("{RFC1123}")
+      |> case do
+        {:ok, date} -> date
+        _ -> nil
+      end
+
     items =
       :xmerl_xpath.string('/channel/item', channel)
       |> Enum.map(fn item ->
@@ -65,6 +73,7 @@ defmodule FeedParser.Parser.RSS2 do
        site_url: link,
        title: title,
        image_url: image,
+       last_updated: last_updated,
        items: items
      }}
   end

lib/parser/rssinjson.ex

@@ -23,6 +23,14 @@ defmodule FeedParser.Parser.RSSInJSON do
     title = channel["title"]
     link = channel["link"]
 
+    last_updated =
+      channel["lastBuildDate"]
+      |> Timex.parse("{RFC1123}")
+      |> case do
+        {:ok, date} -> date
+        _ -> nil
+      end
+
     image =
       case channel do
         %{"image" => %{"url" => url}} -> url
@@ -59,6 +67,7 @@ defmodule FeedParser.Parser.RSSInJSON do
        site_url: link,
        title: title,
        image_url: image,
+       last_updated: last_updated,
        items: items
      }}
   end

test/fixtures/rss2/feed.xml

@@ -5,8 +5,8 @@
       <link>http://liftoff.msfc.nasa.gov/</link>
       <description>Liftoff to Space Exploration.</description>
       <language>en-us</language>
-      <pubDate>Tue, 10 Jun 2003 04:00:00 GMT</pubDate>
-      <lastBuildDate>Tue, 10 Jun 2003 09:41:01 GMT</lastBuildDate>
+      <pubDate>Tue, 10 Jun 2003 04:00:00 UTC</pubDate>
+      <lastBuildDate>Tue, 10 Jun 2003 09:41:01 UTC</lastBuildDate>
       <docs>http://blogs.law.harvard.edu/tech/rss</docs>
       <generator>Weblog Editor 2.0</generator>
       <managingEditor>editor@example.com</managingEditor>

test/fixtures/rssinjson/feed.json

@@ -6,8 +6,8 @@
             "title": "Scripting News",
             "link": "http://scripting.com/",
             "description": "Scripting News, the weblog started in 1994 that bootstrapped the blogging revolution. 🚀",
-            "pubDate": "Sat, 31 Aug 2019 18:04:35 GMT",
-            "lastBuildDate": "Sat, 31 Aug 2019 22:49:49 GMT",
+            "pubDate": "Sat, 31 Aug 2019 18:04:35 UTC",
+            "lastBuildDate": "Sat, 31 Aug 2019 22:49:49 UTC",
             "language": "en-us",
             "copyright": "&copy; 1994-2019 <a href=\"http://davewiner.com/\">Dave Winer</a>.",
             "generator": "oldSchool v0.5.29",

test/parser/atom_test.exs

@@ -15,6 +15,7 @@ defmodule FeedParser.Parser.AtomTest do
     assert {:ok, %FeedParser.Feed{} = feed} = Atom.parse_feed(parsed_data)
     assert feed.site_url == "http://example.org/"
     assert feed.title == "Example Feed"
+    assert feed.last_updated == ~U[2003-12-13 18:30:02Z]
     assert [%FeedParser.Item{} = item] = feed.items
     assert item.guid == "urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a"
     assert item.title == "Atom-Powered Robots Run Amok"

test/parser/jsonfeed_test.exs

@@ -14,7 +14,7 @@ defmodule FeedParser.Parser.JSONFeedTest do
     assert {:ok, %FeedParser.Feed{} = feed} = JSONFeed.parse_feed(parsed_data)
     assert feed.title == "My Example Feed"
     assert feed.site_url == "https://example.org/"
-    IO.inspect(feed.items)
+    assert feed.last_updated == nil
     assert [%FeedParser.Item{} = item2, %FeedParser.Item{} = item1] = feed.items
     assert item2.guid == "2"
     assert item2.content == "This is a second item."

test/parser/rss2_test.exs

@@ -15,6 +15,7 @@ defmodule FeedParser.Parser.RSS2Test do
     assert {:ok, %FeedParser.Feed{} = feed} = RSS2.parse_feed(parsed_data)
     assert feed.title == "Liftoff News"
     assert feed.site_url == "http://liftoff.msfc.nasa.gov/"
+    assert feed.last_updated == ~U[2003-06-10 09:41:01Z]
     assert [%FeedParser.Item{} = item] = feed.items
     assert item.title == "Star City"
     assert item.url == "http://liftoff.msfc.nasa.gov/news/2003/news-starcity.asp"

test/parser/rssinjson_test.exs

@@ -14,6 +14,7 @@ defmodule FeedParser.Parser.RSSInJSONTest do
     assert {:ok, %FeedParser.Feed{} = feed} = RSSInJSON.parse_feed(parsed_data)
     assert feed.title == "Scripting News"
     assert feed.site_url == "http://scripting.com/"
+    assert feed.last_updated == ~U[2019-08-31 22:49:49Z]
     assert [%FeedParser.Item{} = item] = feed.items
     assert item.url == "http://scripting.com/2019/08/31.html#a151142"
     assert item.guid == "http://scripting.com/2019/08/31.html#a151142"