Google Meet integration with Liferay

				
					// GoogleMeetServiceImpl.java
package com.ignek.google.meet;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Date;
import java.util.List;
import java.util.TimeZone;
import java.util.UUID;

import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.extensions.java6.auth.oauth2.AuthorizationCodeInstalledApp;
import com.google.api.client.extensions.jetty.auth.oauth2.LocalServerReceiver;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow;
import com.google.api.client.googleapis.auth.oauth2.GoogleClientSecrets;
import com.google.api.client.googleapis.javanet.GoogleNetHttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.gson.GsonFactory;
import com.google.api.client.util.DateTime;
import com.google.api.client.util.store.FileDataStoreFactory;
import com.google.api.services.calendar.Calendar;
import com.google.api.services.calendar.CalendarScopes;
import com.google.api.services.calendar.model.ConferenceData;
import com.google.api.services.calendar.model.ConferenceSolutionKey;
import com.google.api.services.calendar.model.CreateConferenceRequest;
import com.google.api.services.calendar.model.Event;
import com.google.api.services.calendar.model.EventAttendee;
import com.google.api.services.calendar.model.EventDateTime;
import com.google.api.services.calendar.model.EventReminder;
import com.ignek.google.meet.model.GoogleMeetResponse;
import com.liferay.petra.string.StringPool;
import com.liferay.portal.kernel.log.Log;
import com.liferay.portal.kernel.log.LogFactoryUtil;
import com.liferay.portal.kernel.util.Validator;

@Component(immediate = true, service = GoogleMeetService.class)
public class GoogleMeetServiceImpl implements GoogleMeetService {

	@Override
	public GoogleMeetResponse updateGoogleMeetEvent(String eventId, String title, String location, String[] emails,
			String description, String startTime, String endTime, String timeZone, Integer repeat) {
		try {
			final NetHttpTransport HTTP_TRANSPORT = GoogleNetHttpTransport.newTrustedTransport();
			Calendar service = new Calendar.Builder(HTTP_TRANSPORT, GsonFactory.getDefaultInstance(), 
getCredentials(HTTP_TRANSPORT)).setApplicationName(APPLICATION_NAME).build();
			String calendarId = "primary";
			
			Event event = Validator.isNull(eventId) ? new Event() : service.events().get(calendarId, eventId).execute();
			
			event.setSummary(title);
			event.setLocation(location);
			event.setDescription(description);
			
			TimeZone userTimeZone = TimeZone.getTimeZone(timeZone); 
			DateTime startDateTime = new DateTime(new Date(convertDate(startTime).getTime() 
- userTimeZone.getRawOffset()));
			EventDateTime start = new EventDateTime().setDateTime(startDateTime).setTimeZone(timeZone);
			event.setStart(start);
			
			DateTime endDateTime = new DateTime(new Date(convertDate(endTime).getTime() 
- userTimeZone.getRawOffset()));
			EventDateTime end = new EventDateTime().setDateTime(endDateTime).setTimeZone(timeZone);
			event.setEnd(end);
			
			ConferenceSolutionKey conferenceSKey = new ConferenceSolutionKey();
			conferenceSKey.setType( "hangoutsMeet");
			CreateConferenceRequest createConferenceReq = new CreateConferenceRequest();
			createConferenceReq.setRequestId(UUID.randomUUID().toString());
			createConferenceReq.setConferenceSolutionKey(conferenceSKey);
			ConferenceData conferenceData = new ConferenceData();
			conferenceData.setCreateRequest(createConferenceReq);
			event.setConferenceData(conferenceData);
			List recurrences = new ArrayList<>();
			recurrences.add(getrecurrenceByRepeatType(repeat));
		
			event.setRecurrence(recurrences);
			List attendees = new ArrayList<>();
			for (String email : emails) {
				EventAttendee attendee = new EventAttendee();
				attendees.add(attendee.setEmail(email));
			}
			event.setAttendees(attendees);
			
			EventReminder[] reminderOverrides = new EventReminder[] {
					new EventReminder().setMethod("email").setMinutes(24 * 60),
					new EventReminder().setMethod("popup").setMinutes(10) };
			Event.Reminders reminders = new Event.Reminders().setUseDefault(false)
.setOverrides(Arrays.asList(reminderOverrides));
			event.setReminders(reminders);
			
			event = Validator.isNull(eventId)
					? service.events().insert(calendarId, event).setConferenceDataVersion(1)
.setSendNotifications(true).execute()
					: service.events().update(calendarId, eventId, event).execute();

			return GoogleMeetResponse.of(event.getHangoutLink(), event.getId());
		} catch (Exception e) {
			log.error(e.getMessage(), e);
			return GoogleMeetResponse.fail(e.getMessage());
		}
	}

	@Override
	public String getGoogleMeetLink(String eventId) {
		try {
			final NetHttpTransport HTTP_TRANSPORT = GoogleNetHttpTransport.newTrustedTransport();
			Calendar service = new Calendar.Builder(HTTP_TRANSPORT, GsonFactory.getDefaultInstance(),
 getCredentials(HTTP_TRANSPORT)).setApplicationName(APPLICATION_NAME).build();
			String calendarId = "primary";
			Event event = Validator.isNull(eventId) ? new Event() : service.events().get(calendarId, eventId)
.execute();
			return event.getHangoutLink();
		} catch (Exception e) {
			log.error(e.getMessage(), e);
		}
		return StringPool.BLANK;
	}

	@Override
	public void deleteGoogleMeetEvent(String eventId) {
		try {
			final NetHttpTransport HTTP_TRANSPORT = GoogleNetHttpTransport.newTrustedTransport();
			Calendar service = new Calendar.Builder(HTTP_TRANSPORT, GsonFactory.getDefaultInstance(),
 getCredentials(HTTP_TRANSPORT)).setApplicationName(APPLICATION_NAME).build();
			String calendarId = "primary";
			service.events().delete(calendarId, eventId).execute();
		} catch (Exception e) {
			log.error(e.getMessage(), e);
		}
	}
	
	private String getrecurrenceByRepeatType(int repeat) {
		if (repeat == REPEAT_TYPE_NO) {
			return "RRULE:FREQ=DAILY;COUNT=1";
		}
		if (repeat == REPEAT_TYPE_DAILY) {
			return "RRULE:FREQ=DAILY;INTERVAL=1";
		}
		if (repeat == REPEAT_TYPE_WEEKLY) {
			return "RRULE:FREQ=WEEKLY;BYDAY=MO;INTERVAL=1";
		}
		if (repeat == REPEAT_TYPE_MONTHLY) {
			return "RRULE:FREQ=MONTHLY;BYMONTHDAY=1;INTERVAL=1";
		}
		if (repeat == REPEAT_TYPE_YEARLY) {
			return "RRULE:FREQ=YEARLY;BYMONTH=1;BYMONTHDAY=1";
		}
		return StringPool.BLANK;
	}
	
	private Date convertDate(String date) throws ParseException {
	    DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm");
	    return formatter.parse(date); 
	}
	
	private static Credential getCredentials(final NetHttpTransport HTTP_TRANSPORT) throws IOException {
		
		InputStream inputStream = GoogleMeetServiceImpl.class.getResourceAsStream("/credentials.json");  
// Add credentials.json to */src/main/resources/credentials.json
		if (Validator.isNull(inputStream)) {
			throw new FileNotFoundException("Resource not found: credentials.json");
		}

		GoogleClientSecrets clientSecrets = GoogleClientSecrets.load(GsonFactory.getDefaultInstance(), 
new InputStreamReader(inputStream));
		GoogleAuthorizationCodeFlow flow = new GoogleAuthorizationCodeFlow
				.Builder(HTTP_TRANSPORT, GsonFactory.getDefaultInstance(), clientSecrets, 
Collections.singletonList(CalendarScopes.CALENDAR))
				.setDataStoreFactory(new FileDataStoreFactory(new java.io.File("tokens")))
				.setAccessType("offline")
				.setApprovalPrompt("force")
				.setScopes(CalendarScopes.all())
				.build();
		
		LocalServerReceiver receiver = new LocalServerReceiver.Builder().setPort(9080).build();  
//check port is already assigned or not and put same port number as entered in redirect URIs for Callback

		return new AuthorizationCodeInstalledApp(flow, receiver).authorize("user");
	}

	private static final String APPLICATION_NAME = "Testing Application";
	private static final int REPEAT_TYPE_NO = 0;
	private static final int REPEAT_TYPE_DAILY = 1;
	private static final int REPEAT_TYPE_WEEKLY = 2;
	private static final int REPEAT_TYPE_MONTHLY = 3;
	private static final int REPEAT_TYPE_YEARLY = 4;
	private static final Log log = LogFactoryUtil.getLog(GoogleMeetServiceImpl.class);
}