I have almost completed pub/sub fake-server, that requests user password and email (from the client), compares this info with database and returns data back. It has 'api_in' and 'api_out' frames and then the JSON. The publisher takes and processes all the info without a hitch, but it doesn't seem to send anything back to the client (subscriber) and I don't know why, cause it is connected to the subsequent port.
And I know that this implementation is not a classic PUB/SUB pattern, but that was prerequisite, to do it like that.
I tried different pub/sub options, but nothing has changed.
Server
let zmq = require('zeromq');
const sqlite3 = require('sqlite3').verbose();
const DBSOURCE = "./db.sqlite";
let db = new sqlite3.Database(DBSOURCE, (err) => {
if(err) {
console.error(err.message);
throw err;
} else {
console.log('Connected to SQLite database');
db.run(`CREATE TABLE users (
user_id INTEGER,
email TEXT,
passw TEXT)`,
(err) => {
if (err) {
// Table already created
} else {
// Creating rows
let insert = 'INSERT INTO users (user_id, email, passw) VALUES (?,?,?)';
db.run(insert, [123098, 'phillCollins@gmail.com','5502013']);
db.run(insert, [42424242,'dukenukem3d@mustdie.com','RodriguesShallLiveLong']);
db.run(insert, [5,'yourchick@yandex.ru','semolinaAndPain666']);
}
})
}
});
const args = require('minimist')(process.argv.slice(2));
const pubSocket = zmq.socket('pub', null);
pubSocket.bindSync(`tcp://127.0.0.1:${args['pub']}`);
const subSocket = zmq.socket('sub', null);
subSocket.subscribe('api_in');
subSocket.on('message', function(data) {
let message = data.toString().replace(/api_in/g, '');
let mes = JSON.parse(message);
let api_out = 'api_out';
let errorWrongPWD = 'WRONG_PWD';
let errorWrongFormat = 'WRONG_FORMAT';
if(mes.type = 'login') {
db.get(`SELECT user_id from users WHERE email = ? and passw = ?`, [mes.email, mes.pwd], function(err, row) {
if(err) {
console.log(err);
} else {
if(row) {
let msg = {
msg_id: mes.msg_id,
user_id: row.user_id,
status: 'ok'
}
let outMessage = api_out + JSON.stringify(msg);
console.log(outMessage);
subSocket.send(outMessage);
} else {
let msg = {
msg_id: mes.msg_id,
status: 'error',
error: mes.email == '' || mes.pwd == '' ? errorWrongFormat : errorWrongPWD
}
console.log(msg);
let outMessage = api_out + JSON.stringify(msg);
subSocket.send(outMessage);
}
}
});
}
});
subSocket.bindSync(`tcp://127.0.0.1:${args['sub']}`);
client
let zmq = require('zeromq');
let uniqid = require('uniqid');
let readline = require('readline').createInterface({
input: process.stdin,
output: process.stdout
});
const args = require('minimist')(process.argv.slice(2));
const pubSocket = zmq.socket('pub', null);
let pubSocketTCP = `tcp://127.0.0.1:${args['sub']}`;
pubSocket.connect(pubSocketTCP);
const subSocket = zmq.socket('sub', null);
let subSocketTCP = `tcp://127.0.0.1:${args['pub']}`;
subSocket.connect(subSocketTCP);
let api_in = 'api_in';
let secondFrame = {
type: 'login',
email: '',
pwd: '',
msg_id: uniqid()
}
readline.question('What is your email? \n', (email) => {
secondFrame.email = email;
readline.question('What is your password \n', (pwd) => {
secondFrame.pwd = pwd;
let msg = api_in + JSON.stringify(secondFrame);
console.log(msg);
pubSocket.send(msg);
});
});
subSocket.subscribe('api_out');
subSocket.on('message', (response) => {
/* let res = response.toString().replace('api_out');
let responseParsed = JSON.parse(res);
console.log(responseParsed.status);
if(response.status == 'error') console.log(response.error); */
console.log(response);
});
I want the server side to send info back.
