Add YoutubeClient.getRecommendationPlaylist

src/main/java/YouTubeSearchApi/YoutubeClient.java

@@ -1,5 +1,6 @@
 package YouTubeSearchApi;
 
+import YouTubeSearchApi.entity.YoutubePlaylist;
 import YouTubeSearchApi.entity.YoutubeVideo;
 import YouTubeSearchApi.exception.NoResultFoundException;
 import YouTubeSearchApi.utility.Utils;
@@ -13,6 +14,8 @@
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 public class YoutubeClient {
 
@@ -39,7 +42,7 @@ public List<YoutubeVideo> search(String keywords, int maxResults) throws IOExcep
         }
 
         if (!foundFeatureFlag) {
-            throw new NoResultFoundException("what you searched was unfortunately not found or doesn't exist. keywords: " + keywords);
+            throw new NoResultFoundException("What you searched was unfortunately not found or doesn't exist. keywords: " + keywords);
         }
 
 
@@ -112,4 +115,36 @@ public YoutubeVideo getInfoByVideoUrl(String videoUrl) throws IOException {
 
         return YoutubeVideo.getParsedOEmbedObject(videoObject);
     }
+
+    public YoutubePlaylist getRecommendation(String videoId) throws IOException, NoResultFoundException {
+        String requestUrl = this.YOUTUBE_BASE_URL + "watch?v=" + videoId;
+
+        String pageContent = Utils.httpRequest(requestUrl);
+
+        Pattern pattern = Pattern.compile(
+                "\"compactRadioRenderer\"(.+?)\"compactVideoRenderer\"",
+                Pattern.CASE_INSENSITIVE
+        );
+        Matcher matcher = pattern.matcher(pageContent);
+
+        if (matcher.find()) {
+            String compactRadioRenderer = matcher.group();
+            compactRadioRenderer = "{" + compactRadioRenderer.substring(0,
+                    compactRadioRenderer.length() - ",{\"compactVideoRenderer\"".length());
+
+            System.out.println(compactRadioRenderer);
+
+            Gson gson = new Gson();
+
+            JsonObject compactRadioRendererObject = gson.fromJson(compactRadioRenderer, JsonObject.class)
+                                                        .get("compactRadioRenderer")
+                                                        .getAsJsonObject();
+            YoutubePlaylist youtubePlaylist = YoutubePlaylist.parseCompactRadioRenderer(compactRadioRendererObject);
+
+            return youtubePlaylist;
+        }
+        else {
+            throw new NoResultFoundException("Cannot find any recommendation for videoId: " + videoId);
+        }
+    }
 }

src/main/java/YouTubeSearchApi/entity/YoutubePlaylist.java

@@ -0,0 +1,94 @@
+package YouTubeSearchApi.entity;
+
+import com.google.gson.JsonObject;
+
+public class YoutubePlaylist {
+
+    private String id;
+    private String url;
+    private String title;
+    private String thumbnailUrl;
+    private String metadataUrl;
+
+    public YoutubePlaylist(String id, String url, String title, String thumbnailUrl, String metaDataUrl) {
+        this.id = id;
+        this.url = url;
+        this.title = title;
+        this.thumbnailUrl = thumbnailUrl;
+        this.metadataUrl = metaDataUrl;
+    }
+
+    public static YoutubePlaylist parseCompactRadioRenderer(JsonObject compactRadioRendererObject) {
+        String playlistId = compactRadioRendererObject.get("playlistId").getAsString();
+
+        String thumbnailUrl = compactRadioRendererObject.get("thumbnail").getAsJsonObject()
+                .get("thumbnails").getAsJsonArray()
+                .get(0).getAsJsonObject()
+                .get("url").getAsString();
+
+        String title = compactRadioRendererObject.get("title").getAsJsonObject()
+                .get("simpleText").getAsString();
+
+        String playlistUrl = compactRadioRendererObject.get("shareUrl").getAsString()
+                .replace("\\u0026", "&");
+
+        String metaDataUrl = compactRadioRendererObject.get("navigationEndpoint").getAsJsonObject()
+                .get("commandMetadata").getAsJsonObject()
+                .get("webCommandMetadata").getAsJsonObject()
+                .get("url").getAsString()
+                .replace("\\u0026", "&");
+
+        return new YoutubePlaylist(playlistId, playlistUrl, title, thumbnailUrl, metaDataUrl);
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getUrl() {
+        return url;
+    }
+
+    public void setUrl(String url) {
+        this.url = url;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getThumbnailUrl() {
+        return thumbnailUrl;
+    }
+
+    public void setThumbnailUrl(String thumbnailUrl) {
+        this.thumbnailUrl = thumbnailUrl;
+    }
+
+    public String getMetadataUrl() {
+        return metadataUrl;
+    }
+
+    public void setMetadataUrl(String metadataUrl) {
+        this.metadataUrl = metadataUrl;
+    }
+
+    @Override
+    public String toString() {
+        return "YoutubePlaylist{" +
+                "id='" + id + '\'' +
+                ", url='" + url + '\'' +
+                ", title='" + title + '\'' +
+                ", thumbnailUrl='" + thumbnailUrl + '\'' +
+                ", metadataUrl='" + metadataUrl + '\'' +
+                '}';
+    }
+}

src/main/java/YouTubeSearchApi/utility/Utils.java

@@ -6,6 +6,8 @@
 import java.net.URL;
 import java.net.URLConnection;
 import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 
 public class Utils {
 
@@ -42,4 +44,9 @@ public static String httpRequest(String url) throws IOException {
 
         return stringBuilder.toString();
     }
+
+    public static String readFile(String path, Charset encoding) throws IOException {
+        byte[] encoded = Files.readAllBytes(Paths.get(path));
+        return new String(encoded, encoding);
+    }
 }

src/test/java/YouTubeSearchApi/TestYoutubeClientGetRecommendation.java

@@ -0,0 +1,18 @@
+package YouTubeSearchApi;
+
+import YouTubeSearchApi.entity.YoutubePlaylist;
+import YouTubeSearchApi.exception.NoResultFoundException;
+
+import java.io.IOException;
+
+public class TestYoutubeClientGetRecommendation {
+    public static void main(String[] args) {
+        YoutubeClient client = new YoutubeClient();
+        try {
+            YoutubePlaylist youtubePlaylist = client.getRecommendation("oCrwzN6eb4Q");
+            System.out.println(youtubePlaylist);
+        } catch (IOException | NoResultFoundException e) {
+            e.printStackTrace();
+        }
+    }
+}