writing this little domain search app, it should sequentially search the .com of each item in an array, but it keeps searching for test1. even if I do a console log within the search function it tells me the value of x is test2, and test 3. do I need to remove the listener or something?
I get the following output
domain test1.com
Domain Name: TEST1.COM
domain test2.com
Domain Name: TEST1.COM
domain test3.com
Domain Name: TEST1.COM
app.js
var port = 43;
var net = require('net');
var host = 'whois.internic.net';
var dotCom = new net.Socket();
var c = 0;
var connections = 0;
var dotComStatus;
dotCom.setEncoding('ascii');
var searches = ['test1', 'test2', 'test3'];
search(searches.shift());
function chkconnections(z) {
if (connections <= 0) {
if (searches.length >= 1) {
process.nextTick(function() {
search(searches.shift());
});
}
}
}
function search(x) {
var q = "domain " + x + ".com\r\n";
dotCom.connect(port, host, function() {
dotCom.write(q);
console.log(q);
connections++;
});
dotCom.on('data', function(data) {
c++;
if (c == 2) {
dotComStatus = data.split('\n')[1];
dotCom.on('close', function() {
console.log(dotComStatus);
connections--;
chkconnections();
});
}
});
}
There are several obvious problems with this code. Firstly putting the close event inside the data event is a bad idea. If the connection closed before data was received that section of code would never be reached. Next is there is a big problem with the section with
c++;
if (c == 2)
Since you never reset c to 0 the next line dotComStatus = data.split('\n')[1]; is never executed. But then the socket closes and the event closed is triggered. And this is executed again.
console.log(dotComStatus);
connections--;
chkconnections();
But the value of dotComStatus has not changed since c was equal to 0. There are many examples of how to do this connect/data/end flow that is common in NodeJS.
var port = 43;
var net = require('net');
var host = 'whois.internic.net';
var searches = ['test1', 'test2', 'test3'];
search(searches.shift());
function chkconnections(z) {
if(searches.length > 0)
search(searches.shift());
}
function search(x) {
var dotCom = new net.Socket();
dotCom.setEncoding('ascii');
var q = "domain " + x + ".com\r\n";
dotCom.connect(port, host, function() {
dotCom.write(q);
});
var data = ""; // holding place until socket closes
dotCom.on('data', function(chunk) {
data += chunk; // add chunk to data
});
dotCom.on("end", function() {
// socket closed
dotComStatus = data.split('\n')[7]; // Should be 'Domain Name: blah'
console.log(dotComStatus);
chkconnections(); // move on to next
});
};