curl -d "user_id=100" http://localhost:3000/users
curl http://localhost:3000/users
curl -d "user1=100&user2=200" http://localhost:3000/chatrooms
curl -d "user_id=100" http://localhost:3000/users
curl http://localhost:3000/users
curl -d "user1=100&user2=200" http://localhost:3000/chatrooms