ChatApp Server

Summary

A back-end server side message dispatcher that works with a client(https://github.com/rodolfovilaca/ChatAppClient). It's a multithreaded program that broadcasts all messages to clients and saves all its timeline in a MySQL database.

Design Patterns

• Singleton: A single object responsible to communicate with MySQL (CRUD operations) as we don't want several connections to the DB.
• DAO(Data Access Objects): model used to create objects in the program and save them as data in MySQL.

Instructions

MySQL user setup on production:

> mysql -u root -p
mysql> GRANT ALL PRIVILEGES ON *.* TO ‘ChatAppClient’@‘localhost' WITH GRANT OPTION;
mysql> FLUSH PRIVILEGES;
mysql> exit

How to open ports in Digital Ocean

DB Port

> sudo ufw allow 3306/tcp
> sudo service ufw restart

Socket Port

> sudo ufw allow 5000/tcp 
> sudo service ufw restart

How to generate and run the JAR on production:

> git clone https://github.com/rodolfovilaca/ChatAppServer
> cd ChatAppServer
> mv ./MANIFEST.MF ./bin
> mv ./libs/* ./bin
> cd bin
> jar cfm ChatAppServer.jar MANIFEST.MF * org.rodolfo.bancodedadosmysql.jar mysql-connector-java-5.1.42-bin.jar

Run jar on the foreground:

> java -jar ChatAppServer.jar

Run jar on the background

> nohup java -jar ChatAppServer.jar &
> tail -f nohup.out

Kill background process

> ps -ef
> kill -9 $PID_NUMBER