Files
tixto_server/app.js
T

107 lines
3.8 KiB
JavaScript

var app = require('express')();
var server = require('http').Server(app);
var io = require('socket.io')(server);
var mysql = require('mysql');
var db_config = {
host: 'us-cdbr-iron-east-04.cleardb.net',
user: 'bc7fa7fdf1822b',
password: 'f62b55b3',
database: 'heroku_99e764eb3c2ab7e'
};
var con;
var port = process.env.PORT || 3000;
server.listen(port, () => console.log('serving on port: ' + port));
app.get('/', function (req, res) {
res.sendFile(__dirname + '/index.html');
});
function handleDisconnect() {
con = mysql.createConnection(db_config); // Recreate the connection, since
// the old one cannot be reused.
con.connect(function(err) { // The server is either down
if(err) { // or restarting (takes a while sometimes).
console.log('error when connecting to db...settingTimeout then connecting again');
setTimeout(handleDisconnect, 2000); // We introduce a delay before attempting to reconnect,
} // to avoid a hot loop, and to allow our node script to
}); // process asynchronous requests in the meantime.
// If you're also serving http, display a 503 error.
con.on('error', function(err) {
console.log('db error', err);
if(err.code === 'PROTOCOL_CONNECTION_LOST') { // Connection to the MySQL server is usually
handleDisconnect(); // lost due to either server restart, or a
} else { // connnection idle timeout (the wait_timeout
throw err; // server variable configures this)
}
});
}
handleDisconnect();
io.on('connection', function (socket) {
console.log('Client connected: ' + socket.id);
/*
* Client sends a request with its position and avatar link
* Returns the inital messages and assigned user_id
*/
socket.on('initial', (input) => {
console.log('Position: ' + input.position.long + ' ' + input.position.lat);
let long = input.position.long;
let lat = input.position.lat;
let avatar = input.avatar;
var sql = 'SELECT * FROM messages, users WHERE messages.user_id = users.id HAVING (6371393 * acos(cos(radians((?))) * cos(radians(messages.lat)) * cos(radians(messages.lng) - radians((?))) + sin(radians((?))) * sin(radians(messages.lat))) < 200) ORDER BY messages.id;'
con.query(sql, [lat, long, lat], function (err, result, fields) {
if (err) throw err;
console.log(result);
socket.emit('initMessages', result);
console.log('sent all initial messages');
});
var newUserSql = 'INSERT INTO users (avatar) VALUES (?)';
con.query(newUserSql, [avatar], function (err, result, fields) {
if (err) throw err;
if (result) {
var user_id = result.insertId;
console.log("User id given: " + user_id);
socket.emit("userId", {userId: user_id});
} else {
socket.emit("userId", {userId: 1});
}
});
});
socket.on('newMessage', function(msg) {
var sql = "INSERT INTO messages (lat, lng, text, user_id) VALUES (?, ?, ?, ?)";
var currTime = new Date().toString();
con.query(sql, [msg.lat, msg.long, msg.text, msg.user_id], function(err, result, fields) {
if (err) throw err;
var msgId = result.insertId;
console.log('Message with id ' + msgId + ' inserted!');
var uploadedMsg = {
id: msgId,
user_id: msg.user_id,
text: msg.text,
created: currTime,
long: msg.long,
lat: msg.lat,
avatar: msg.avatar
};
io.emit('newMessage', uploadedMsg);
});
});
socket.on('disconnect', function() {
console.log('Client disconnected: ' + socket.id);
});
});