JS_WebSocket_Gaming_Project

Development of Game Server

[Done] Single client to Single server
[Done] Using express-ws to activate WebSocket
[Done] Multiple clients to Single server (broadcast msg to other all clients)
[Done] Detection of client's disconnection
[Done] Identification of each client
[Done] Create database by sql3 & sqlite
[Done] Read player data from database before starting game
[Done] Add a status in db to check whether player is been used or not
[Done] Update db account status if player login
[Done] Different players have different token while connecting to server (personal account)
[Done] Update db player status (character, position, direction, ...) if player moves

[Done] Player's character controls (left, right, up, down)
[Done] Characters always stay in the center
[Done] Login page before playing game
[Done] Body & Item block
[Done] One client can see player controlled by another client
[Done] Two client controll different player
[Done] Three client controll different player by different computer (only three now)
[Done] Clients login at different time but still having same view (body block & direction)

In order for npm to manage our modules (create a configuration file named “package.json”)

npm init

npm add --save express
npm add express express-ws

npm install --save ws
npm ls ws

To run this game, in a terminal placed in the folder where “server.js” is located

node server.js

node db.js

node db_init.js

If having this problem : An invalid form control with name='xxx' is not focusable, it means that "require" in html element inputbox causes some problmes.
According to this : window.location.href doesn't redirect, if type of inputbox is "submit", window.location.href won't work. We need to use type "button".
According to this : How to use a function from another file using require(), because we didn't use module type in our project, we cannot use import/export in our js files, we need to use require()/module.export to implement module concept.
We had problem of broadcasting while changing module ws to express-ws, but solving by following this : Minimal express-ws broadcast to all clients
In order to reconnect once client gets valid token from server, we can refresh client website to update url's token by following this : WebSocket: How to automatically reconnect after it dies.
Because of using async-await function with return value to deal with database, we can create functions in another js files by following this : 彻底搞懂 async await 的return问题. But we didn't really use this kind of function eventually as async-await functions are not used to returning values.
To connect to server by different computer, we need to change "localhost" to "IPv4 Address" (from Wireless LAN Wi-Fi) in client.js
According to What is the (function(){})() construct in JavaScript?, we can reload init.js just right after client gets its own id by giving the function in init.js a varable name.