Validate JSONFeed version and rework feed detection

application/controllers/FeedController.php

@@ -193,7 +193,6 @@ public function editAction(): void
         ]);
 
         $form->on(Form::ON_SUCCESS, function () {
-            // TODO: Should have a different message for deletion
             Notification::success($this->translate('Updated feeds'));
             $this->redirectNow('__CLOSE__');
         });

library/Feeds/FeedReader.php

@@ -8,6 +8,8 @@
 use Icinga\Module\Feeds\Parser\RSSParser;
 use Icinga\Module\Feeds\Parser\RSS1Parser;
 use Icinga\Module\Feeds\Parser\Result\Feed;
+use Icinga\Module\Feeds\Parser\InvalidFeedDataException;
+use Icinga\Module\Feeds\Parser\InvalidFeedTypeException;
 
 use Icinga\Application\Config;
 use Icinga\Application\Icinga;
@@ -73,44 +75,32 @@ protected function parse(string $rawResponse): ?Feed
     {
         Benchmark::measure('Started parsing feed');
 
-        switch ($this->type) {
-            case FeedType::Auto:
-                try {
-                    return RSSParser::parse($rawResponse);
-                } catch (Exception $ex) {
-                    // Not an RSS 2.0 feed
-                }
-
-                try {
-                    return RSS1Parser::parse($rawResponse);
-                } catch (Exception $ex) {
-                    // Not an RSS 1.0 feed
-                }
-
-                try {
-                    return AtomParser::parse($rawResponse);
-                } catch (Exception $ex) {
-                    // Not an Atom feed
-                }
-
-                try {
-                    return JsonfeedParser::parse($rawResponse);
-                } catch (Exception $ex) {
-                    // Not an JSONFeed feed
-                }
-
-                throw new Exception('Unsupported feed type or invalid data in feed');
-            case FeedType::RSS:
-                return RSSParser::parse($rawResponse);
-            case FeedType::RSS1:
-                return RSS1Parser::parse($rawResponse);
-            case FeedType::Atom:
-                return AtomParser::parse($rawResponse);
-            case FeedType::Jsonfeed:
-                return JsonfeedParser::parse($rawResponse);
-            default:
-                throw new Exception('Unsupported feed type');
+        return match ($this->type) {
+            FeedType::Auto => $this->parseAuto($rawResponse),
+            FeedType::RSS => RSSParser::parse($rawResponse),
+            FeedType::RSS1 => RSS1Parser::parse($rawResponse),
+            FeedType::Atom => AtomParser::parse($rawResponse),
+            FeedType::Jsonfeed => JsonfeedParser::parse($rawResponse),
+            default => throw new InvalidFeedTypeException('Unsupported feed type'),
+        };
+    }
+
+
+    protected function parseAuto(string $rawResponse): ?Feed
+    {
+        $parsers = [RSSParser::class, RSS1Parser::class, AtomParser::class, JsonfeedParser::class];
+
+        foreach ($parsers as $parser) {
+            try {
+                return $parser::parse($rawResponse);
+            } catch (InvalidFeedDataException $e) {
+                throw new Exception('Invalid data in feed: ' . $e->getMessage(), $e->getCode(), $e);
+            } catch (Exception) {
+                // Let's try the next format
+            }
         }
+
+        throw new Exception('Unsupported feed type');
     }
 
     /**

library/Feeds/Parser/AtomParser.php

@@ -24,7 +24,7 @@ public static function parse(string $raw): Feed
         $xmlElement = new SimpleXMLElement($raw);
 
         if ($xmlElement->getName() !== 'feed') {
-            throw new Exception('Invalid Atom-Feed');
+            throw new InvalidFeedTypeException('Invalid Atom-Feed');
         }
 
         $xmlElement->rewind();
@@ -174,8 +174,7 @@ protected static function parseDateTime(string $dateStr): ?DateTime
             try {
                 $datetime = new DateTime($dateStr);
             } catch (Exception $ex) {
-                // NOTE: Nothing to do here, but be ultimately failed to parse
-                // the time
+                // NOTE: Nothing to do here, but be ultimately failed to parse the time
                 $datetime = false;
             }
         }

library/Feeds/Parser/InvalidFeedDataException.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Icinga\Module\Feeds\Parser;
+
+use Icinga\Exception\IcingaException;
+
+/**
+ * InvalidFeedDataException is a custom Exception we use in the feed auto detection
+ * to differentiate between errors detecting a feed type and a parsing error.
+ * Use InvalidFeedDataException to communicate parsing issues to the user.
+ */
+class InvalidFeedDataException extends IcingaException
+{
+}

library/Feeds/Parser/InvalidFeedTypeException.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Icinga\Module\Feeds\Parser;
+
+use Icinga\Exception\IcingaException;
+
+/**
+ * InvalidFeedTypeException is a custom Exception we use in the feed auto detection
+ * to differentiate between errors detecting a feed type and a parsing error.
+ * Use InvalidFeedTypeException to tell the auto detection to try the next parser.
+ */
+class InvalidFeedTypeException extends IcingaException
+{
+}

library/Feeds/Parser/JsonfeedParser.php

@@ -6,6 +6,7 @@
 use Icinga\Module\Feeds\Parser\Result\FeedItem;
 
 use Exception;
+use JsonException;
 use DateTime;
 use DateTimeInterface;
 
@@ -14,17 +15,28 @@
  */
 class JsonfeedParser
 {
+    protected const JSONFEED_V10 = 'https://jsonfeed.org/version/1';
+    protected const JSONFEED_V11 = 'https://jsonfeed.org/version/1.1';
+
     /**
      * parse tries to parse the given string into a Feed object
      */
     public static function parse(string $raw): Feed
     {
-        $json = json_decode($raw, true, 512, JSON_THROW_ON_ERROR);
+        try {
+            $json = json_decode($raw, true, 512, JSON_THROW_ON_ERROR);
+        } catch (JsonException) {
+            throw new InvalidFeedTypeException('Invalid JSONfeed');
+        }
+
         if ($json === null) {
-            throw new Exception('Invalid JSONfeed');
+            throw new InvalidFeedTypeException('Invalid JSONfeed');
         }
 
-        // TODO: validate version field
+        $version = $json['version'] ?? '';
+        if (!str_contains($version, self::JSONFEED_V10)) {
+            throw new InvalidFeedDataException('Unsupported JSONfeed version');
+        }
 
         return static::parseFeed($json);
     }
@@ -41,7 +53,7 @@ protected static function parseFeed(array $json): Feed
         $items = $json['items'] ?? null;
 
         if ($items === null) {
-            throw new Exception('JSONfeed contains no items');
+            throw new InvalidFeedDataException('JSONfeed contains no items');
         }
 
         foreach ($items as $jsonItem) {
@@ -63,8 +75,7 @@ protected static function parseDateTime(string $dateStr): ?DateTime
             try {
                 $datetime = new DateTime($dateStr);
             } catch (Exception $ex) {
-                // NOTE: Nothing to do here, but be ultimately failed to parse
-                // the time
+                // NOTE: Nothing to do here, but be ultimately failed to parse the time
                 $datetime = false;
             }
         }

library/Feeds/Parser/RSS1Parser.php

@@ -25,7 +25,7 @@ public static function parse(string $raw): Feed
         $xmlElement->registerXPathNamespace('dc', 'http://purl.org/dc/elements/1.1/');
 
         if ($xmlElement->getName() !== 'RDF') {
-            throw new Exception('Invalid RSS1.0-Feed');
+            throw new InvalidFeedTypeException('Invalid RSS1.0-Feed');
         }
 
         $xmlElement->rewind();

library/Feeds/Parser/RSSParser.php

@@ -24,7 +24,7 @@ public static function parse(string $raw): Feed
         $xmlElement = new SimpleXMLElement($raw);
 
         if ($xmlElement->getName() !== 'rss') {
-            throw new Exception('Invalid RSS2.0-Feed');
+            throw new InvalidFeedTypeException('Invalid RSS2.0-Feed');
         }
 
         $xmlElement->rewind();

test/php/library/Feeds/Parser/JsonfeedParserTest.php

@@ -3,20 +3,53 @@
 namespace Tests\Icinga\Module\Feeds\Parser;
 
 use Icinga\Module\Feeds\Parser\JsonfeedParser;
+use Icinga\Module\Feeds\Parser\InvalidFeedDataException;
+use Icinga\Module\Feeds\Parser\InvalidFeedTypeException;
 use Icinga\Module\Feeds\Parser\Result\Feed;
 
 use PHPUnit\Framework\TestCase;
 
 final class JsonfeedParserTest extends TestCase
 {
-    public function testParse()
+    // https://jsonfeed.org/version/1.0
+    public function testParseJsonFeed10()
     {
-        $raw = file_get_contents(__DIR__ .'/testdata/jsonfeed.json');
+        $raw = file_get_contents(__DIR__ .'/testdata/jsonfeed1-0.json');
 
         $actual = JsonfeedParser::parse($raw);
 
         $this->assertTrue($actual instanceof Feed);
-        $this->assertSame($actual->title, 'JSONFeed Sample Feed');
+        $this->assertSame($actual->title, 'JSONFeed 1.0 Sample Feed');
         $this->assertSame(count($actual->getItems()), 1);
     }
+
+    // https://jsonfeed.org/version/1.1
+    public function testParseJsonFeed11()
+    {
+        $raw = file_get_contents(__DIR__ .'/testdata/jsonfeed1-1.json');
+
+        $actual = JsonfeedParser::parse($raw);
+
+        $this->assertTrue($actual instanceof Feed);
+        $this->assertSame($actual->title, 'JSONFeed 1.1 Sample Feed');
+        $this->assertSame(count($actual->getItems()), 2);
+    }
+
+    // Does not exist (yet)
+    public function testParseJsonFeed20()
+    {
+        $raw = file_get_contents(__DIR__ .'/testdata/jsonfeed2-0.json');
+
+        $this->expectException(InvalidFeedDataException::class);
+
+        $actual = JsonfeedParser::parse($raw);
+    }
+
+    // With invalid input
+    public function testParseJsonFeed_NoData()
+    {
+        $this->expectException(InvalidFeedTypeException::class);
+
+        $actual = JsonfeedParser::parse('');
+    }
 }

test/php/library/Feeds/Parser/testdata/jsonfeed.json → test/php/library/Feeds/Parser/testdata/jsonfeed1-0.json

@@ -1,6 +1,6 @@
 {
     "version": "https://jsonfeed.org/version/1",
-    "title": "JSONFeed Sample Feed",
+    "title": "JSONFeed 1.0 Sample Feed",
     "home_page_url": "https://example.org/homepage",
     "feed_url": "https://example.org/feed.json",
     "description": "This is my feed description",

test/php/library/Feeds/Parser/testdata/jsonfeed1-1.json

@@ -0,0 +1,61 @@
+{
+  "version": "https://jsonfeed.org/version/1.1",
+  "title": "JSONFeed 1.1 Sample Feed",
+  "home_page_url": "https://example.org/",
+  "feed_url": "https://example.org/feed.json",
+  "description": "Optional to provide more detail beyond the title.",
+  "user_comment": "Optional and should be ignored by feed readers.",
+  "next_url": "https://example.org/pagination?feed=feed.json&p=17",
+  "icon": "https://example.org/favicon-timeline-512x512.png",
+  "favicon": "https://example.org/favicon-sourcelist-64x64.png",
+  "authors": [
+    {
+      "name": "Optional Author",
+      "url": "https://example.org/authors/optional-author",
+      "avatar": "https://example.org/authors/optional-author/avatar-512x512.png"
+    }
+  ],
+  "language": "en-US",
+  "items": [
+    {
+      "id": "2",
+      "content_text": "This is a second item.",
+      "url": "https://example.org/second-item",
+      "language": "es-mx",
+      "attachments": [
+        {
+          "url": "https://example.org/second-item/audio.ogg",
+          "mime_type": "audio/ogg",
+          "title": "Optional Title",
+          "size_in_bytes": 31415927,
+          "duration_in_seconds": 1800
+        }
+      ]
+    },
+    {
+      "id": "required-unique-string-that-does-not-change: number, guid, url, etc.",
+      "url": "https://example.org/initial-post",
+      "external_url": "https://en.wikipedia.org/w/index.php?title=JSON_Feed",
+      "title": "Optional Title",
+      "content_html": "<p>Optional content for the feed reader. You may also use content_text or both at the same time.</p>",
+      "content_text": "Optional text for simple feeds.",
+      "summary": "Optional summary of the item.",
+      "image": "https://example.org/initial-post/main-img.png",
+      "banner_image": "https://example.org/initial-post/details-banner.png",
+      "date_published": "2021-10-25T19:30:00-01:00",
+      "date_modified": "2021-10-26T19:45:00-01:00",
+      "authors": [
+        {
+          "name": "Optional Author",
+          "url": "https://example.org/authors/optional-author",
+          "avatar": "https://example.org/authors/optional-author/avatar-512x512.png"
+        }
+      ],
+      "tags": [
+        "Optional Tag",
+        "Example"
+      ],
+      "language": "en-US"
+    }
+  ]
+}

test/php/library/Feeds/Parser/testdata/jsonfeed2-0.json

@@ -0,0 +1,7 @@
+{
+    "version": "https://jsonfeed.org/version/2",
+    "title": "JSONFeed 2.0",
+    "home_page_url": "https://example.org/homepage",
+    "feed_url": "https://example.org/feed.json",
+    "description": "JSONFeed 2.0 does not exist (yet)"
+}