add: format american style datetime

lib/domain/dart_rss.dart

@@ -4,14 +4,25 @@ import 'package:dart_rss/domain/atom_feed.dart';
 import 'package:dart_rss/domain/rss1_feed.dart';
 import 'package:dart_rss/domain/rss_feed.dart';
 import 'package:xml/xml.dart' as xml;
+import 'package:intl/intl.dart';
 
 extension SafeParseDateTime on DateTime {
   static DateTime safeParse(String str) {
+    const dateFormatPatterns = [
+      'EEE, d MMM yyyy HH:mm:ss Z',
+    ];
+
     try {
       return DateTime.parse(str);
     } catch (_) {
-      return null;
+      for (final pattern in dateFormatPatterns) {
+        try {
+          final format = DateFormat(pattern);
+          return format.parse(str);
+        } catch (_) {}
+      }
     }
+    return null;
   }
 }
 
@@ -40,56 +51,15 @@ class WebFeed {
     switch (rssVersion) {
       case RssVersion.RSS1:
         final rss1Feed = Rss1Feed.parse(xmlString);
-        return WebFeed(
-          title: rss1Feed.title,
-          description: rss1Feed.description,
-          links: [rss1Feed.link],
-          items: rss1Feed.items
-              .map(
-                (item) => WebFeedItem(
-                  title: item.title,
-                  body: item.description ?? item.dc?.description,
-                  updated: SafeParseDateTime.safeParse(item.dc?.date),
-                  links: [item.link],
-                ),
-              )
-              .toList(),
-        );
+        return WebFeed.fromRss1(rss1Feed);
         break;
       case RssVersion.RSS2:
         final rss2Feed = RssFeed.parse(xmlString);
-        return WebFeed(
-          title: rss2Feed.title,
-          description: rss2Feed.description,
-          links: [rss2Feed.link],
-          items: rss2Feed.items
-              .map(
-                (item) => WebFeedItem(
-                  title: item.title,
-                  body: item.description ?? item.dc?.description,
-                  updated: SafeParseDateTime.safeParse(item.dc?.date),
-                ),
-              )
-              .toList(),
-        );
+        return WebFeed.fromRss2(rss2Feed);
         break;
       case RssVersion.Atom:
         final atomFeed = AtomFeed.parse(xmlString);
-        return WebFeed(
-          title: atomFeed.title,
-          description: atomFeed.subtitle,
-          links: atomFeed.links.map((atomLink) => atomLink.href).toList(),
-          items: atomFeed.items
-              .map(
-                (item) => WebFeedItem(
-                  title: item.title,
-                  body: item.summary,
-                  updated: SafeParseDateTime.safeParse(item.updated),
-                  links: item.links.map((atomLink) => atomLink.href).toList(),
-                ),
-              )
-              .toList(),
-        );
+        return WebFeed.fromAtom(atomFeed);
         break;
       case RssVersion.Unknown:
         throw Error.safeToString(
@@ -100,6 +70,62 @@ class WebFeed {
     }
   }
 
+  static WebFeed fromRss1(Rss1Feed rss1feed) {
+    return WebFeed(
+      title: rss1feed.title ?? rss1feed.dc.title ?? '',
+      description: rss1feed.description ?? rss1feed.dc?.description ?? '',
+      links: [rss1feed.link],
+      items: rss1feed.items
+          .map(
+            (item) => WebFeedItem(
+              title: item.title ?? item.dc?.title ?? '',
+              body: item.description ?? item.dc?.description ?? '',
+              updated: SafeParseDateTime.safeParse(item.dc?.date),
+              links: [item.link],
+            ),
+          )
+          .toList(),
+    );
+  }
+
+  static WebFeed fromRss2(RssFeed rssFeed) {
+    return WebFeed(
+      title: rssFeed.title ?? rssFeed.dc.title ?? '',
+      description: rssFeed.description ?? rssFeed.dc.description ?? '',
+      links: [rssFeed.link],
+      items: rssFeed.items
+          .map(
+            (item) => WebFeedItem(
+              title: item.title ?? item.dc.title ?? '',
+              body: item.description ?? item.dc.description ?? '',
+              updated: SafeParseDateTime.safeParse(item.pubDate) ??
+                  SafeParseDateTime.safeParse(item.dc.date),
+              links: [item.link],
+            ),
+          )
+          .toList(),
+    );
+  }
+
+  static WebFeed fromAtom(AtomFeed atomFeed) {
+    return WebFeed(
+      title: atomFeed.title,
+      description: atomFeed.subtitle,
+      links: atomFeed.links.map((atomLink) => atomLink.href).toList(),
+      items: atomFeed.items
+          .map(
+            (item) => WebFeedItem(
+              title: item.title,
+              body: item.summary ?? item.content,
+              updated: SafeParseDateTime.safeParse(item.updated) ??
+                  SafeParseDateTime.safeParse(item.published),
+              links: item.links.map((atomLink) => atomLink.href).toList(),
+            ),
+          )
+          .toList(),
+    );
+  }
+
   static Future<WebFeed> fromUrl(String url) async {
     final response = await http.get(url);
     return fromXmlString(response.body);

pubspec.yaml

@@ -8,5 +8,7 @@ dependencies:
   xml: ^3.0.0
   http: ^0.11.0
   meta: ^1.0.0
+  intl: any
+
 dev_dependencies:
   test: ^1.0.0

test/real_rss_test.dart

@@ -0,0 +1,27 @@
+import 'package:dart_rss/dart_rss.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('Can this library use for real rss xml?', () {
+    const testFeeds = {
+      'pub.dev feed': 'https://pub.dev/feed.atom',
+      'Flutter Weekly':
+          'https://us17.campaign-archive.com/feed?u=c8d8d18b6e2c6316ddc1d48a0&id=47548a283b',
+      'jQuery blog': 'http://blog.jquery.com/feed/', // <- not use ISO8601
+      'hatena sample': 'https://b.hatena.ne.jp/sample/bookmark.rss', // <- RSS1
+    };
+
+    for (final title in testFeeds.keys) {
+      final url = testFeeds[title];
+      test(title, () async {
+        // given
+        final feed = await WebFeed.fromUrl(url);
+
+        // then
+        expect(feed.title.isNotEmpty, true);
+        expect(feed.items.first.updated is DateTime, true);
+        expect(feed.items.first.links.isNotEmpty, true);
+      });
+    }
+  });
+}

test/safe_parse_date_time_test.dart

@@ -0,0 +1,23 @@
+import 'package:dart_rss/dart_rss.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('about SafeParseDateTime, ', () {
+    test('it can parse ISO-8601', () {
+      final date = SafeParseDateTime.safeParse('2018-04-06T13:02:47Z');
+
+      expect(date.year, 2018);
+      expect(date.month, 4);
+      expect(date.day, 6);
+    });
+
+    test('it can parse American-English-Format', () {
+      final date =
+          SafeParseDateTime.safeParse('Tue, 02 Jul 2019 16:47:24 +0000');
+
+      expect(date.year, 2019);
+      expect(date.month, 7);
+      expect(date.day, 2);
+    });
+  });
+}

test/webfeed_test.dart

@@ -91,7 +91,8 @@ void main() {
         rss2Feed.items.first.body,
         'Lorem ipsum dolor sit amet, consectetur adipiscing elit',
       );
-      expect(rss2Feed.items.first.updated, null);
+      expect(rss2Feed.items.first.updated,
+          DateTime.parse('2018-03-26 14:00:00.000'));
     });
   });
 }