feat: youtube 관련 로직 작성

src/main/java/com/example/hackathon/domain/youtube/service/YoutubeService.java

@@ -0,0 +1,49 @@
+package com.example.hackathon.domain.youtube.service;
+
+import com.google.api.client.json.JsonFactory;
+import com.google.api.client.json.jackson2.JacksonFactory;
+import com.google.api.services.youtube.YouTube;
+import com.google.api.services.youtube.model.SearchListResponse;
+import com.google.api.services.youtube.model.SearchResult;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Service;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
+
+@Service
+public class YoutubeService {
+
+    @Value("${youtube.api.key}")
+    private  String apiKey;
+
+    public String searchVideo(String query) throws IOException {
+        String modifiedQuery = query + " 스트레칭";
+
+        JsonFactory jsonFactory = new JacksonFactory();
+
+        YouTube youtube = new YouTube.Builder(
+                new com.google.api.client.http.javanet.NetHttpTransport(),
+                jsonFactory,
+                Request -> {})
+                .build();
+        YouTube.Search.List search = youtube.search().list(Collections.singletonList("id,snippet"));
+
+        search.setKey(apiKey);
+        search.setQ(modifiedQuery);
+
+        SearchListResponse searchResponse = search.execute();
+
+        List<com.google.api.services.youtube.model.SearchResult> searchResultList = searchResponse.getItems();
+
+        if (searchResultList != null && searchResultList.size() > 0) {
+            SearchResult searchResult = searchResultList.get(0); //검색 결과 중 첫 번째 동영상 정보 가져오기
+
+            String videoId = searchResult.getId().getVideoId();
+            String videoTitle = searchResult.getSnippet().getTitle();
+
+            return "Title: " + videoTitle + "\nURL: https://www.youtube.com/watch?v=" + videoId;
+        }
+        return "검색 결과가 없습니다";    }
+}