Using NSURLRequest to pass key-value pairs to PHP script with POST

Question

Hi,

I'm fairly new to objective-c, and am looking to pass a number of key-value pairs to a PHP script using POST. I'm using the following code but the data just doesn't seem to be getting posted through. I tried sending stuff through using NSData as well, but neither seem to be working.

 NSDictionary* data = [NSDictionary dictionaryWithObjectsAndKeys:
    @"bob", @"sender",
    @"aaron", @"rcpt",
    @"hi there", @"message",
    nil];

 NSURL *url = [NSURL URLWithString:@"http://myserver.com/script.php"];
 NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

 [request setHTTPMethod:@"POST"];
 [request setHTTPBody:[NSData dataWithBytes:data length:[data count]]];

  NSURLResponse *response;
  NSError *err;
  NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&err];
  NSLog(@"responseData: %@", content);

This is getting sent to this simple script to perform a db insert:

<?php $sender = $_POST['sender'];
      $rcpt = $_POST['rcpt'];
      $message = $_POST['message'];

      //script variables
      include ("vars.php");

      $con = mysql_connect($host, $user, $pass);
      if (!$con)
      {
        die('Could not connect: ' . mysql_error());
      }

      mysql_select_db("mydb", $con);

      mysql_query("INSERT INTO php_test (SENDER, RCPT, MESSAGE) 
      VALUES ($sender, $rcpt, $message)");

      echo "complete"
?>

Any ideas?

Answer 1

Edit: Has been fixed in OP.

---

This may not be your sole problem (I don't know my way around objective-c), but here goes:

mysql_query("INSERT INTO php_test (SENDER, RCPT, MESSAGE) 
VALUES ($sender, $rcpt, $message)");

You're not quote-enclosing your strings - MySQL is bound to have a hissy fit over that.

mysql_query("INSERT INTO php_test (SENDER, RCPT, MESSAGE) 
VALUES ('$sender', '$rcpt', '$message')");

Beyond that, generally, even if your script is not reachable from the outside, you shouldn't trust user input and either use mysql_real_escape_string() to escape your values before you insert them into the SQL statement to prevent SQL injection, or use prepared statements (preferred) - otherwise single quotes in your legitimate data will break the SQL statement's syntax.

Entirely ungraceful example for reference:

mysql_query("INSERT INTO php_test (SENDER, RCPT, MESSAGE) 
VALUES ('" . mysql_real_escape_string($sender) ."',"
." '" . mysql_real_escape_string($rcpt) ."',"
." '" . mysql_real_escape_string($message) ."')");

Answer 2

This line [request setHTTPBody:[NSData dataWithBytes:data length:[data count]]]; looks way wrong to me.

I think you want: [request setAllHTTPHeaderFields:data];

Secondly, you will find the Cocoa framework capitalizes the first letter of your field names before sending them (annoyingly). You might have to make some changes to cope with that.

Answer 3

If you are going to do a lot of form posting, I'd recommend skipping NSURLRequest and using ASIHTTPRequest instead. IMHO, it's well documented and offers an straightforward way to interact with webservices.

Answer 4

Thanks for the suggestions everyone. In the end i managed to solve the issue by using stuff given here.

Code:

NSString *myRequestString = @"sender=my%20sender&rcpt=my%20rcpt&message=hello";
NSData *myRequestData = [ NSData dataWithBytes: [ myRequestString UTF8String ] length: [ myRequestString length ] ];
NSMutableURLRequest *request = [ [ NSMutableURLRequest alloc ] initWithURL: [ NSURL URLWithString: @"http://people.bath.ac.uk/trs22/insert.php" ] ]; 
[ request setHTTPMethod: @"POST" ];
[ request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"content-type"];
[ request setHTTPBody: myRequestData ];
NSURLResponse *response;
NSError *err;
NSData *returnData = [ NSURLConnection sendSynchronousRequest: request returningResponse:&response error:&err];
NSString *content = [NSString stringWithUTF8String:[returnData bytes]];
NSLog(@"responseData: %@", content);

Answer 5

This didnt work for me... NSString *post = [NSString stringWithFormat:@"userudid=%@", [udid stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]]; NSLog(@"%@",post); NSData *postData = [NSData dataWithBytes:[post UTF8String] length:[post length]]; //[udid dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES]; NSLog(@"%@",postData); //NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]];

NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://www.myserver.com/myapp/readtags2.php"]];
[request setURL:url];
[request setHTTPMethod:@"POST"];
//[request setValue:postLength forHTTPHeaderField:@"Content-Length"];
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[request setHTTPBody:postData];
NSURLResponse *response;
NSError *error;
NSData *urlData = [NSURLConnection sendSynchronousRequest:request
                                returningResponse:&response
                                            error:&error];

NSString *content = [NSString stringWithUTF8String:[urlData bytes]];
NSLog(@"responseData: %@", content);

Answer 6

This is wrong:

[NSData dataWithBytes:[post UTF8String] length:[post length]]

The length should be expressed in bytes not in count of UTF8 characters. Instead of this line you should use:

NSData *data = [post dataUsingEncoding: NSUTF8StringEncoding];