index.js

var express = require( "express" );
var app = express();
var fs = require( 'fs' );
var Papa = require( 'papaparse' );
var bodyParser = require( "body-parser" );
var session = require( "express-session" );
var cookieParser = require( "cookie-parser" );
var api = require( './tweet_api/api' );
var set_trends = null;

//
app.set( "view engine", "ejs" );
app.set( "views", "./views" );
app.use( express.static( __dirname + "/public" ) );
app.use( bodyParser.json() );
app.use( bodyParser.urlencoded( { extended: false } ) );
app.use( cookieParser() );

app.use(
  session( {
    key: 'user_sid',
    secret: "cmpe_280_secure_string",
    resave: false,
    saveUninitialized: false,
    cookie: {
      expires: 6000000
    }
  } )
);

//Only user allowed is admin
var Users = [
  {
    username: "admin",
    password: "admin"
  }
];

var sessionChecker = ( req, res, next ) =>
{
  if ( req.session.user && req.cookies.user ) {
    res.redirect( '/home' );
  } else {
    next();
  }
};
var worldCities;
var content = fs.readFileSync( "worldcities.csv", "utf8" );
var loadWorldCities = function ()
{
  Papa.parse( content, {
    header: false,
    complete: function ( results )
    {
      worldCities = results.data;
      worldCities = worldCities.map( element => ( { city: element[ 0 ], latitude: element[ 2 ], longitude: element[ 3 ], country: element[ 4 ] } ) )
      console.log( "CSV Loaded" )
    }
  } )
};

app.get( "/", sessionChecker, function ( req, res )
{
  //check if user session exits
  if ( worldCities ) {
  } else {
    loadWorldCities();
  }
  res.redirect( "/login" );
} );

app.route( '/login' )
  .get( sessionChecker, ( req, res ) =>
  {
    res.render( "login", { error: "", dynamicLoad: "Login" } );
  } )
  .post( ( req, res ) =>
  {
    var username = req.body.username,
      password = req.body.password;
    api.getUser( username, password, req, res );
  } );

app.get( '/home', ( req, res ) =>
{
  if ( req.session.user && req.cookies.user ) {
    // api.get_trends(req, res); 
    // res.render("home"); 
    if ( set_trends == null ) {
      api.get_trends( req, res, ( trends ) =>
      {
        // console.log( trends )
        set_trends = trends
        res.render( "home", { "topics": JSON.stringify( trends ) } )
      } );
    } else {
      res.render( "home", { "topics": JSON.stringify( set_trends ) } )
    }
  } else {
    res.redirect( '/login' );
  }
} );

app.get( '/logout', ( req, res ) =>
{
  if ( req.session.user && req.cookies.user ) {
    res.clearCookie( 'user_sid' );
    res.redirect( '/' );
  } else {
    res.redirect( '/login' );
  }
} );

app.get( '/signup', ( req, res ) =>
{
  return res.render( 'login', { error: "", dynamicLoad: "Sign Up" } );
} );

app.post( '/signup', ( req, res ) =>
{
  api.storeUser( req.body.username, req.body.password, req, res )

} );

//get from database
app.get( '/fetchtweets/:query', function ( req, res )
{
  api.get_request( req, res );

} )

//delete from database
app.post( '/deletetweets/:query', function ( req, res )
{
  api.delete_request( req, res );

} )

//add to database
app.post( '/tweets', ( req, res ) =>
{
  api.post_request( req, res );

} );

app.get( '/analysis/:query', ( req, res ) =>
{
  // console.log("api " + worldCities)
  api.analysis( req, res, worldCities );
} );

app.get( '/trends/:place?', ( req, res ) =>
{
  api.get_trends( req, res );
} );

app.use( function ( req, res, next )
{
  res.status( 404 ).send( "Sorry can't find that!" )
} );

var server = app.listen( 3000, function ()
{
  console.log( "Server listening on port 3000" );
} );