JS Meetup #23: Outline

meetup.md

Game backend from scratch using NodeJS

Click here to register!

Prerequisite

• Fundamental's of NodeJS.
• Basic understanding of eventloop.
• Basics of ES6.
• Working of REST api's.
• How to play CHESS game.

About Me

• Vineesh N P

Backend Developer [NodeJS and Python] @ TechJini

• @vineeshvalsalan

Intro to game backend

• Few words about what a game backend is supposed to do.
• Existing languages and implementations.

Intro to sockets

• What, why, when sockets?
• Sockets vs REST api's

socket.io

• Intro to the websocket libraries
• Reason to choose library

Game with a case study of CHESS :

We will try to take, chess as a case study, and explain the rest with a code base biased to chess.

Architecture : Simple

• An image of simple architecture
• Explaining the components

game state

• What is game state.
• What are the components of game state.

Turing Machine based model: state processing(why in scalability)

• Games are basically a state in memory, which changes wrt to the input from the user.
• This is similar to the turning machine designed by Alan Turing.
• Architecture and game state is compared to a Turing Machine

CODE:

• Code to connect to socket client
• Code to send and receive data from client and server

concepts of room in games

• Explain the relevance of rooms
• How to create and subscribe to rooms

Implementing Actions

• Defining methods for each actions
• Starting the game
• Game moves
• Handling conflicts, like when a player makes a move he is not supposed to make.
• Winner declaration, and resetting the game board.

using engine to validate moves

• Writing the entire game might be time consuming, thus some parts could be reused by some libraries.

CODE:

• Implementing concept of rooms
• Doing move validations

Scaling

• Vertical scaling and Horizontal scaling.
• Socket scaling using broker.
• Game-state scaling using cache servers.
• Message queues.
• Reverse proxy using nginx.

Architecture : Complex

• Image of architecture involving the above components

Challenges

• Node is not designed for game backend.
• Handling computations on event loop.
• Importance of doing CPU intensive tasks using golang/rust.
• Need of timers.

Suggestions

• Forget es5 approach.
• es6 / typescript will be lifesavers.
• Security with tokens
• Rather than writing from scratch, you could use frameworks.[But don't expect a long term support]
• Do profiling to find out time consuming functions.
• For production use game engines.

Conclusion

• Conclusion of JS and Game development.
• Q&A.