support enclosure & refactoring

lib/domain/rss_category.dart

@@ -1,23 +1,18 @@
 import 'package:xml/xml.dart';
 
 class RssCategory {
-  String domain;
-  String value;
+  final String domain;
+  final String value;
 
   RssCategory(this.domain, this.value);
 
-  factory RssCategory.parse(XmlElement node) {
-    var domain = node.getAttribute("domain");
-    var value = node.text;
+  factory RssCategory.parse(XmlElement element) {
+    if (element == null) {
+      return null;
+    }
+    var domain = element.getAttribute("domain");
+    var value = element.text;
 
     return new RssCategory(domain, value);
   }
-
-  @override
-  String toString() {
-    return '''
-      domain: $domain
-      value: $value
-    ''';
-  }
 }

lib/domain/rss_content.dart

@@ -16,8 +16,11 @@ class RssContent {
 
   RssContent(this.value, this.images);
 
-  factory RssContent.parse(XmlElement node) {
-    final content = node.text;
+  factory RssContent.parse(XmlElement element) {
+    if (element == null) {
+      return null;
+    }
+    final content = element.text;
     final images = <String>[];
     _imagesRegExp.allMatches(content).forEach((match) {
       images.add(match.group(1));

lib/domain/rss_enclosure.dart

@@ -0,0 +1,19 @@
+import 'package:xml/xml.dart';
+
+class RssEnclosure {
+  final String url;
+  final String type;
+  final int length;
+
+  RssEnclosure(this.url, this.type, this.length);
+
+  factory RssEnclosure.parse(XmlElement element) {
+    if (element == null) {
+      return null;
+    }
+    var url = element.getAttribute("url");
+    var type = element.getAttribute("type");
+    var length = int.tryParse(element.getAttribute("length") ?? "0");
+    return new RssEnclosure(url, type, length);
+  }
+}

lib/domain/rss_item.dart

@@ -1,9 +1,11 @@
 import 'package:webfeed/domain/media/media.dart';
 import 'package:webfeed/domain/rss_category.dart';
 import 'package:webfeed/domain/rss_content.dart';
+import 'package:webfeed/domain/rss_enclosure.dart';
 import 'package:webfeed/domain/rss_source.dart';
 import 'package:webfeed/util/helpers.dart';
 import 'package:xml/xml.dart';
+import 'package:webfeed/util/helpers.dart';
 
 class RssItem {
   final String title;
@@ -18,6 +20,7 @@ class RssItem {
   final RssSource source;
   final RssContent content;
   final Media media;
+  final RssEnclosure enclosure;
 
   RssItem({
     this.title,
@@ -31,45 +34,25 @@ class RssItem {
     this.source,
     this.content,
     this.media,
+    this.enclosure,
   });
 
   factory RssItem.parse(XmlElement element) {
-    var title = xmlGetString(element, "title", strict: false);
-    var description = xmlGetString(element, "description", strict: false);
-    var link = xmlGetString(element, "link", strict: false);
-
-    var categories = element.findElements("category").map((element) {
-      return new RssCategory.parse(element);
-    }).toList();
-
-    var guid = xmlGetString(element, "guid", strict: false);
-    var pubDate = xmlGetString(element, "pubDate", strict: false);
-    var author = xmlGetString(element, "author", strict: false);
-    var comments = xmlGetString(element, "comments", strict: false);
-
-    RssSource source;
-    try {
-      source = new RssSource.parse(element.findElements("source").first);
-    } on StateError {}
-
-    RssContent content;
-    try {
-      content =
-          new RssContent.parse(element.findElements("content:encoded").first);
-    } on StateError {}
-
     return new RssItem(
-      title: title,
-      description: description,
-      link: link,
-      categories: categories,
-      guid: guid,
-      pubDate: pubDate,
-      author: author,
-      comments: comments,
-      source: source,
-      content: content,
+      title: findElementOrNull(element, "title")?.text,
+      description: findElementOrNull(element, "description")?.text,
+      link: findElementOrNull(element, "link")?.text,
+      categories: element.findElements("category").map((element) {
+        return new RssCategory.parse(element);
+      }).toList(),
+      guid: findElementOrNull(element, "guid")?.text,
+      pubDate: findElementOrNull(element, "pubDate")?.text,
+      author: findElementOrNull(element, "author")?.text,
+      comments: findElementOrNull(element, "comments")?.text,
+      source: RssSource.parse(findElementOrNull(element, "source")),
+      content: RssContent.parse(findElementOrNull(element, "content:encoded")),
       media: Media.parse(element),
+      enclosure: RssEnclosure.parse(findElementOrNull(element, "enclosure")),
     );
   }
 

lib/domain/rss_source.dart

@@ -6,18 +6,13 @@ class RssSource {
 
   RssSource(this.url, this.value);
 
-  factory RssSource.parse(XmlElement node) {
-    var url = node.getAttribute("url");
-    var value = node.text;
+  factory RssSource.parse(XmlElement element) {
+    if (element == null) {
+      return null;
+    }
+    var url = element.getAttribute("url");
+    var value = element.text;
 
     return new RssSource(url, value);
   }
-
-  @override
-  String toString() {
-    return '''
-      url: $url
-      value: $value
-    ''';
-  }
 }

test/rss_test.dart

@@ -72,6 +72,9 @@ void main() {
     expect(feed.items.first.source.url, "https://foo.bar.news/1?source");
     expect(feed.items.first.source.value, "Foo Bar");
     expect(feed.items.first.comments, "https://foo.bar.news/1/comments");
+    expect(feed.items.first.enclosure.url, "http://www.scripting.com/mp3s/weatherReportSuite.mp3");
+    expect(feed.items.first.enclosure.length, 12216320);
+    expect(feed.items.first.enclosure.type, "audio/mpeg");
 
     expect(feed.items.first.content.value, "<img width=\"1000\" height=\"690\" src=\"https://test.com/image_link\"/> Test content<br />");
     expect(feed.items.first.content.images.first, "https://test.com/image_link");

test/xml/RSS.xml

@@ -47,6 +47,7 @@
             <source url="https://foo.bar.news/1?source">Foo Bar</source>
             <comments>https://foo.bar.news/1/comments</comments>
             <content:encoded><![CDATA[<img width="1000" height="690" src="https://test.com/image_link"/> Test content<br />]]></content:encoded>
+            <enclosure url="http://www.scripting.com/mp3s/weatherReportSuite.mp3" length="12216320" type="audio/mpeg" />
         </item>
         <item>
             <title>Section 1.10.32 of "de Finibus Bonorum et Malorum", written by Cicero in 45 BC</title>