Extract Video Short Description in YouTube.

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamInfoItemExtractor.java

@@ -288,4 +288,19 @@ private OffsetDateTime getDateFromPremiere() throws ParsingException {
             throw new ParsingException("Could not parse date from premiere:  \"" + startTime + "\"");
         }
     }
+
+    @Nullable
+    @Override
+    public String getShortDescription() throws ParsingException {
+
+        if (videoInfo.has("detailedMetadataSnippets")) {
+            return getTextFromObject(videoInfo.getArray("detailedMetadataSnippets").getObject(0).getObject("snippetText"));
+        }
+
+        if (videoInfo.has("descriptionSnippet")) {
+            return getTextFromObject(videoInfo.getObject("descriptionSnippet"));
+        }
+
+        return null;
+    }
 }

extractor/src/main/java/org/schabi/newpipe/extractor/stream/StreamInfoItem.java

@@ -32,6 +32,7 @@ public class StreamInfoItem extends InfoItem {
     private final StreamType streamType;
 
     private String uploaderName;
+    private String shortDescription;
     private String textualUploadDate;
     @Nullable
     private DateWrapper uploadDate;
@@ -92,6 +93,14 @@ public void setUploaderAvatarUrl(final String uploaderAvatarUrl) {
         this.uploaderAvatarUrl = uploaderAvatarUrl;
     }
 
+    public String getShortDescription() {
+        return shortDescription;
+    }
+
+    public void setShortDescription(final String shortDescription) {
+        this.shortDescription = shortDescription;
+    }
+
     @Nullable
     public String getTextualUploadDate() {
         return textualUploadDate;

extractor/src/main/java/org/schabi/newpipe/extractor/stream/StreamInfoItemExtractor.java

@@ -116,4 +116,14 @@ public interface StreamInfoItemExtractor extends InfoItemExtractor {
     @Nullable
     DateWrapper getUploadDate() throws ParsingException;
 
+
+    /**
+     * Get the video's short description.
+     *
+     * @return The video's short description or {@code null} if not provided by the service.
+     * @throws ParsingException if there is an error in the extraction
+     */
+    @Nullable
+    default String getShortDescription() throws ParsingException { return null; }
+
 }

extractor/src/main/java/org/schabi/newpipe/extractor/stream/StreamInfoItemsCollector.java

@@ -101,6 +101,11 @@ public StreamInfoItem extract(StreamInfoItemExtractor extractor) throws ParsingE
         } catch (Exception e) {
             addError(e);
         }
+        try {
+            resultItem.setShortDescription(extractor.getShortDescription());
+        } catch (Exception e) {
+            addError(e);
+        }
 
         return resultItem;
     }

extractor/src/test/java/org/schabi/newpipe/extractor/services/youtube/search/YoutubeSearchExtractorTest.java

@@ -343,4 +343,34 @@ public void testUploaderAvatar() throws IOException, ExtractionException {
             }
         }
     }
+
+    public static class VideoDescription extends DefaultSearchExtractorTest {
+        private static SearchExtractor extractor;
+        private static final String QUERY = "44wLAzydRFU";
+
+        @BeforeClass
+        public static void setUp() throws Exception {
+            YoutubeParsingHelper.resetClientVersionAndKey();
+            YoutubeParsingHelper.setNumberGenerator(new Random(1));
+            NewPipe.init(new DownloaderFactory().getDownloader(RESOURCE_PATH + "video_description"));
+            extractor = YouTube.getSearchExtractor(QUERY, singletonList(VIDEOS), "");
+            extractor.fetchPage();
+        }
+
+        @Override public SearchExtractor extractor() { return extractor; }
+        @Override public StreamingService expectedService() { return YouTube; }
+        @Override public String expectedName() { return QUERY; }
+        @Override public String expectedId() { return QUERY; }
+        @Override public String expectedUrlContains() { return "youtube.com/results?search_query=" + QUERY; }
+        @Override public String expectedOriginalUrlContains() { return "youtube.com/results?search_query=" + QUERY; }
+        @Override public String expectedSearchString() { return QUERY; }
+        @Nullable @Override public String expectedSearchSuggestion() { return null; }
+        @Override public InfoItem.InfoType expectedInfoItemType() { return InfoItem.InfoType.STREAM; }
+
+        @Test
+        public void testVideoDescription() throws IOException, ExtractionException {
+            final List<InfoItem> items = extractor.getInitialPage().getItems();
+            assertNotNull(((StreamInfoItem) items.get(0)).getShortDescription());
+        }
+    }
 }