Task #4034: delete question and its answers

check if session has this question and throw unauthorized exception if
not

src/main/java/de/thm/arsnova/controller/QuestionController.java

@@ -113,4 +113,10 @@ public class QuestionController extends AbstractController {
 		return questions;
 		
 	}
+	
+	@RequestMapping(value="/session/{sessionKey}/questions/{questiondId}", method=RequestMethod.DELETE)
+	@ResponseBody
+	public void deleteAnswersAndQuestion(@PathVariable String sessionKey, @PathVariable String questionId, HttpServletResponse response) {
+		questionService.deleteQuestion(sessionKey, questionId);
+	}
 }

src/main/java/de/thm/arsnova/dao/CouchDBDao.java

@@ -61,6 +61,7 @@ import de.thm.arsnova.entities.User;
 import de.thm.arsnova.entities.VisitedSession;
 import de.thm.arsnova.exceptions.ForbiddenException;
 import de.thm.arsnova.exceptions.NotFoundException;
+import de.thm.arsnova.exceptions.UnauthorizedException;
 import de.thm.arsnova.services.IFeedbackService;
 import de.thm.arsnova.services.ISessionService;
 import de.thm.arsnova.services.IUserService;
@@ -602,4 +603,33 @@ public class CouchDBDao implements IDatabaseDao {
 		}
 		return null;
 	}
+
+	@Override
+	public void deleteQuestion(String sessionKey, String questionId) {
+		Session s = this.getSessionFromKeyword(sessionKey);
+		try {
+			Document question = this.getDatabase().getDocument(questionId);
+			if(!question.getString("sessionId").equals(s.get_id())) {
+				throw new UnauthorizedException();
+			}
+		} catch (IOException e) {
+			logger.error("could not find question {}", questionId);
+		}
+		
+		try {
+			View view = new View("answer/cleanup");
+			view.setKey(URLEncoder.encode("\"" + questionId + "\"", "UTF-8"));
+			ViewResults results = this.getDatabase().view(view);	
+			
+			for(Document d : results.getResults()) {
+				Document answer = this.getDatabase().getDocument(d.getId());
+				this.getDatabase().deleteDocument(answer);
+			}
+			Document question = this.getDatabase().getDocument(questionId);
+			this.getDatabase().deleteDocument(question);
+			
+		} catch(Exception e) {
+			logger.error("Could not delete question and its answers with id {}", questionId);
+		} 
+	}
 }

src/main/java/de/thm/arsnova/dao/IDatabaseDao.java

@@ -45,4 +45,5 @@ public interface IDatabaseDao {
 	public LoggedIn registerAsOnlineUser(User u, Session s);
 	public void updateSessionOwnerActivity(Session session);
 	public List<String> getQuestionIds(String sessionKey);
+	public void deleteQuestion(String sessionKey, String questionId);
 }
\ No newline at end of file

src/main/java/de/thm/arsnova/services/IQuestionService.java

@@ -30,4 +30,5 @@ public interface IQuestionService {
 	public List<Question> getSkillQuestions(String sessionkey);
 	public int getSkillQuestionCount(String sessionkey);
 	public List<String> getQuestionIds(String sessionKey);
+	public void deleteQuestion(String sessionKey, String questionId);
 }
\ No newline at end of file

src/main/java/de/thm/arsnova/services/QuestionService.java

@@ -74,4 +74,11 @@ public class QuestionService implements IQuestionService {
 	public List<String> getQuestionIds(String sessionKey) {
 		return databaseDao.getQuestionIds(sessionKey);
 	}
+
+	@Override
+	@Authenticated
+	public void deleteQuestion(String sessionKey, String questionId) {
+		databaseDao.deleteQuestion(sessionKey, questionId);
+		
+	}
 }

src/test/java/de/thm/arsnova/dao/StubDatabaseDao.java

@@ -169,4 +169,10 @@ public class StubDatabaseDao implements IDatabaseDao {
 		return null;
 	}
 
+	@Override
+	public void deleteQuestion(String sessionKey, String questionId) {
+		// TODO Auto-generated method stub
+		
+	}
+
 }