Call function on Server from iOS app - Objective C - ios

Question

If you are familiar with Parse.com's Javascript SDK, this is what I am trying to do for my own server for my iOS app (Objective-c). I want to be able to send some a string to the function that is on my server, have the server run its function and then return a string to the app or some xml or JSON data.
Is this even possible?
I am new to doing something like this having an app make a call to a server. I have looked into opening a port on my server, but have been unable to find a way to receive data back to the iOS app. (I found this lib but its for OS X https://github.com/armadsen/ORSSerialPort). Also Im not sure if I have a function run with an open port on the server. So how can I set it up so I can make a call to my server and run a function?
Any help would be much appreciated.

Answer 1

You just need to POST data to your server.
Port could be anything you want.
Host your script with a domain url so that you can make network request publicly.
You can try this function:
-(NSData *)post:(NSString *)postString url:(NSString*)urlString{
//Response data object
NSData *returnData = [[NSData alloc]init];
//Build the Request
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:urlString]];
[request setHTTPMethod:#"POST"];
[request setValue:[NSString stringWithFormat:#"%lu", (unsigned long)[postString length]] forHTTPHeaderField:#"Content-length"];
[request setHTTPBody:[postString dataUsingEncoding:NSUTF8StringEncoding]];
//Send the Request
returnData = [NSURLConnection sendSynchronousRequest: request returningResponse: nil error: nil];
//Get the Result of Request
NSString *response = [[NSString alloc] initWithBytes:[returnData bytes] length:[returnData length] encoding:NSUTF8StringEncoding];
bool debug = YES;
if (debug && response) {
NSLog(#"Response >>>> %#",response);
}
return returnData;
}
And here is how you use it:
NSString *postString = [NSString stringWithFormat:#"param=%#",param];
NSString *urlString = #"https://www.yourapi.com/yourscript.py";
NSData *returnData = [self post:postString url:urlString];
PHP
<?php
$response=array();
if(isset($_POST['param'])){
$response['success'] = true;
$response['message'] = 'received param = '.$_POST['param'];
}else{
$response['success'] = false;
$response['message'] = 'did not receive param';
}
$json = json_encode($response);
echo $json;