HappyCows

A digital simulation game used as a teaching tool for Professor de Vries at UCSB on the Tragedy of the Commons.

Users Page

Admin Page

Getting Started

You can run this program by using this command: (although you might need to install some dependencies first)

./bin/www 

You can access the game by visiting 127.0.0.1:3000
You can also access subpages like so 127.0.0.1:3000/subpagename

Resetting Tables
If the tables are corrupted in the database you can drop the tables
The uncomment out these functions from app.js

//db.Users.sync();
//db.UserCommons.sync();
//db.Commons.sync();
//db.Configs.sync();
//db.Cows.sync();
//db.TieredTaxings.sync();
//db.UserWealths.sync();

Then run:

node app.js 

Running Locally
Install MySQL on your computer and change accordingly in config/config.js.

Then, you can create tables by following command:

npx sequelize-cli db:migrate 

Or you can use following script to force update tables:

var db = require("models/index")
db.Users.sync({force: true});
....

Or you can uncomment out these functions from app.js :

//db.Users.sync();
//db.UserCommons.sync();
//db.Commons.sync();
//db.Configs.sync();
//db.Cows.sync();
//db.TieredTaxings.sync();
//db.UserWealths.sync();

Then run:

./bin/www

If you want to have demo data, run following command: (no demo data here so will not work currently)

./bin/www

Info

For maintainable application, we have all the database structure logic inside the models folder. We have automatic table creation if they don't exist in database which sequelize provides in the bin/www file - models.sequelize.sync(). We just need to worry about setting up the tables properly which are all located in the models folder. Note when we change data in models, we might need to modify the migrations file of that model.

The SQL queries could be found under the apis folder which we have separated for those needed for the admin as well as for users. We also have a folder named "sql" which holds the cron jobs needed to run the game. These need to be manually added onto the server seperately.

The seeders folder allows us to put in sample data so we could run "npx sequelize-cli db:seed:all" command to put it in our data table. Although we did not put any data into this folder so it would not work.

How to write APIs

STEP 1
Create [your_name].js at /routes directory with following content

var express = require('express');
var router = express.Router();

module.exports = router;

STEP 2
Importing route/[your_name].js in /app.js

var yourNameRouter = require('./routes/your_name');

And add following line to register your route:

app.use('/yourName', yourNameRouter);

Now http://server/yourName/* is all yours.

STEP 3
Create file /apis/your_name/your_api.js and write your api functions like

var db = require("../../models/index"); // model is defined in /model
// assume table banana exists
// get all bananas
function get_banana(req, res) {
  db.Banana.findAll().then((dbRes)=>{
    res.json({success: true, data: dbRes}) // send json request back
  })
}
module.exports = {get_banana};

For req and res structs, refer to expressjs docs.
For db struct, refer to sequelize docs.

STEP 4
Import /apis/your_name/your_api.js at route/[your_name].js

var {get_banana} = require("../apis/admin/users");

And register the subroute

router.get('/banana', get_banana);

Now you can use curl to test it out or visit with browser directly!

Backend Stack

• MySQL
• Sequelize
• Express.js
• Node.js

Reference Docs

Express Article

http://sequelize.readthedocs.io/en/1.7.0/articles/express/

Helpful article on sequelize associations

https://lorenstewart.me/2016/09/12/sequelize-table-associations-joins/

Helpful article explaining migrations & seeds

https://sequelize.org/master/manual/migrations.html

RESTful Info

https://www.restapitutorial.com/lessons/restquicktips.html

Queries

https://sequelize.org/master/manual/raw-queries.html