i made this to save a some info on a file and to read line by line using readline node module
there is two res.send() one is with return . it only return within current function its sitting on . How do i completely exit from then functions?
this just for a test . I know I should use Databases
router.post('/login', (req, res) => {
console.log(req.body);
var lineReader = require('readline').createInterface({
input: require('fs').createReadStream('./users.txt')
});
lineReader.on('line', function (line) {
const lineJson = JSON.parse(line);
if (lineJson["username"] == req.body.username) {
if (lineJson["password"] == req.body.password) {
return res.send({ msg: "matched" });
}
}
})
res.send({msg:"not matched"});
})
simplified
function(){
function(){
return...
}
}
Your problem is related to your experience with the asynchronous nature of nodejs.
You need to use the line-reader in async mode for your tests:
lineReader.eachLine('file.txt', function(line, last, cb) {
console.log(line);
if (/* done */) {
cb(false); // stop reading
} else {
cb();
}
});
Or just read the entire file and then query it as if it was a sql table:
var table = //some asyn read of file
if(user-password match){
return res.send({ msg: "matched" });
}else{
return res.send({msg:"not matched"});
}
You can also read the file in async mode (which is better) and in the callback execute your express logic